Arctic Sea Ice : Forum

Cryosphere => Arctic sea ice => Topic started by: solartim27 on January 01, 2017, 09:01:38 PM

Title: The 2017 melting season
Post by: solartim27 on January 01, 2017, 09:01:38 PM
Too soon?   ;)
Title: Re: The 2017 Melting Season
Post by: DrTskoul on January 01, 2017, 09:32:26 PM
 :o  8)
Title: Re: The 2017 Melting Season
Post by: Pmt111500 on January 01, 2017, 09:34:44 PM
 :-X
Title: Re: The 2017 Melting Season
Post by: Neven on January 01, 2017, 09:36:59 PM
Too late! Couldn't you have opened it 8 hours sooner?  ;) ;D
Title: Re: The 2017 Melting Season
Post by: magnamentis on January 02, 2017, 01:07:00 AM
Just in time LOL, the high was at around 1.6 Celsius / 36F

( and there is still water to see for weeks now and most of the time it was much more open water than right now )

Title: Re: The 2017 Melting Season
Post by: Istari on January 02, 2017, 02:05:11 AM
Too soon?   ;)
Too real ...
Title: Re: The 2017 Melting Season
Post by: Tigertown on January 02, 2017, 07:42:57 AM
I don't know if this will do any damage, but it kind of sneaked in over East Siberia.
Probably just a little light snow.
(http://)
Title: Re: The 2017 Melting Season
Post by: Shared Humanity on January 02, 2017, 10:19:43 PM
Nice to see the Arctic not completely dominated by lows. The North Atlantic cyclone cannon has finally stopped. Lets hope for a polar high dominated rest of the freeze season.
Title: Re: The 2017 Melting Season
Post by: Tigertown on January 02, 2017, 10:34:45 PM
I hate to say it, but I think it just had to re-load.
(http://)
Title: Re: The 2017 Melting Season
Post by: Shared Humanity on January 02, 2017, 11:16:10 PM
As long as those highs remain over Greenland and Siberia, those lows could go spinning out of the North Atlantic into the Arctic forever.
Title: Re: The 2017 Melting Season
Post by: Neven on January 03, 2017, 12:48:25 PM
There's no sense in posting actual images here, as the melting season hasn't started yet.

Come back in March/April, everyone.  :P ;D
Title: Re: The 2017 Melting Season
Post by: Iceismylife on January 08, 2017, 09:34:51 PM
Extent down two days in a row go figure.
Title: Re: The 2017 Melting Season
Post by: Adam Ash on January 08, 2017, 10:09:54 PM
Those lows north of Franz Josef Land will sure shove the ice out Fram pretty efficiently. 

I imagine the severely broken ice pack will respond much faster to wind effects than extensive packed-solid ice would - behaving more like debris on the ocean surface than the former comparatively cohesive pack did during winter. 

Thus the effects of prolonged wind on the night-time Arctic will begin to entail conventional open-ocean dynamics arising from fetch length, wind strength and duration resulting in potentially higher waves and thus further stress on and break up of ice floes even under freezing conditions.
Title: Re: The 2017 Melting Season
Post by: Paddy on January 10, 2017, 07:04:57 AM
Extent down two days in a row go figure.

Four days now (although only by a total of about 94000)
Title: Re: The 2017 Melting Season
Post by: mmghosh on January 10, 2017, 07:33:28 AM
Indeed.  A century break (even if spread out over a few days)...
Title: Re: The 2017 Melting Season
Post by: bbr2314 on January 10, 2017, 07:47:22 AM
00z EURO ups ante and moves 945mb storm up to hr192. Wow.

(http://www.tropicaltidbits.com/analysis/models/ecmwf/2017011000/ecmwf_mslpaNorm_nhem_9.png)
Title: Re: The 2017 Melting Season
Post by: budmantis on January 10, 2017, 08:14:01 AM
Impressive! Have Arctic Ocean low pressure systems ever been known to fall below 945 millibars?
Title: Re: The 2017 Melting Season
Post by: Tigertown on January 10, 2017, 08:48:40 AM
Look at the one on the other side of Alaska. It's no joke.
Title: Re: The 2017 Melting Season
Post by: psymmo7 on January 10, 2017, 10:31:54 AM
945 mbar
Storm?
More like a category 3 Hurricane
Here the definition (for non-meteorologists like me) from globalresourcesnews.com
Category 3 - An extensive Hurricane:
Winds 111-130 mph 178-209 km/hr
Minimum Surface Pressure: 964-945 mbar
Storm Surge: 2.7 - 3.8 m!

Title: Re: The 2017 Melting Season
Post by: peterlvmeng on January 10, 2017, 11:08:38 AM
945 mbar
Storm?
More like a category 3 Hurricane
Here the definition (for non-meteorologists like me) from globalresourcesnews.com
Category 3 - An extensive Hurricane:
Winds 111-130 mph 178-209 km/hr
Minimum Surface Pressure: 964-945 mbar
Storm Surge: 2.7 - 3.8 m!

extratropical cyclone is quite usual at this minimum surface pressure in high latitude.
Title: Re: The 2017 Melting Season
Post by: Mark Tough on January 10, 2017, 01:19:16 PM
945 mbar
Storm?
More like a category 3 Hurricane
Here the definition (for non-meteorologists like me) from globalresourcesnews.com
Category 3 - An extensive Hurricane:
Winds 111-130 mph 178-209 km/hr
Minimum Surface Pressure: 964-945 mbar
Storm Surge: 2.7 - 3.8 m!

extratropical cyclone is quite usual at this minimum surface pressure in high latitude.



Well yes peterlvmeng but the North Atlantic Tropical Cyclones end in November according to NOAA (well at least in the pre- anthropological days) ;)

It's all new now and this is a mind blowing freeze season/melt season... Crazy really.

Funnily enough I predict a really late Max but not a big one - and then boom to MYI and a clear pole in Aug, the latter definition of which will be up for world wide debate !

No models or referenced science just MYL (Multi Year Lurking) :)
Title: Re: The 2017 Melting Season
Post by: Buddy on January 10, 2017, 01:39:54 PM
Just what we need....more warmth on the Atlantic side.... :o
Title: Re: The 2017 Melting Season
Post by: DrTskoul on January 10, 2017, 01:56:50 PM
Just what we need....more warmth on the Atlantic side.... :o

Once started it is difficult to abruptly stop the trend. The lows will keep coming with their warmth thought the wimter... Until the sun start rising above the northern lands, as to stop it we need a large external forcing.
Title: Re: The 2017 Melting Season
Post by: Gray-Wolf on January 10, 2017, 02:04:24 PM
I wonder if you can see a 'cold core' Hurricane?

 I mean if the sea ice is smashed up and the 'relatively' warm, moist, air flowing out of those leads fueling convection in the arctic air above? As the storm grew it would smash more ice /wash up more heat to the surface and so on as it sat over the pole........

A bit 'day after Tomorrow' really but if it's all about the relative sea surface temp to air above a wide enough disrupted ice zone might provide enough heat/moisture to set up unfettered convection?
Title: Re: The 2017 Melting Season
Post by: peterlvmeng on January 10, 2017, 03:05:34 PM
945 mbar
Storm?
More like a category 3 Hurricane
Here the definition (for non-meteorologists like me) from globalresourcesnews.com
Category 3 - An extensive Hurricane:
Winds 111-130 mph 178-209 km/hr
Minimum Surface Pressure: 964-945 mbar
Storm Surge: 2.7 - 3.8 m!

extratropical cyclone is quite usual at this minimum surface pressure in high latitude.



Well yes peterlvmeng but the North Atlantic Tropical Cyclones end in November according to NOAA (well at least in the pre- anthropological days) ;)

It's all new now and this is a mind blowing freeze season/melt season... Crazy really.

Funnily enough I predict a really late Max but not a big one - and then boom to MYI and a clear pole in Aug, the latter definition of which will be up for world wide debate !

No models or referenced science just MYL (Multi Year Lurking) :)

Thanks Mark! I remember a strong and large cyclone with minimum pressure lower than 920hpa pervailed the north pacific outside the Bering strait in Jan of 2011. I tend to think it is quite usual inside the arctic.
Title: Re: The 2017 Melting Season
Post by: peterlvmeng on January 10, 2017, 03:16:08 PM
I wonder if you can see a 'cold core' Hurricane?

 I mean if the sea ice is smashed up and the 'relatively' warm, moist, air flowing out of those leads fueling convection in the arctic air above? As the storm grew it would smash more ice /wash up more heat to the surface and so on as it sat over the pole........

A bit 'day after Tomorrow' really but if it's all about the relative sea surface temp to air above a wide enough disrupted ice zone might provide enough heat/moisture to set up unfettered convection?

You mean the theory which is similar to the mechanism of CISK in the formation of tropical cyclones?
Title: Re: The 2017 Melting Season
Post by: Gray-Wolf on January 10, 2017, 03:25:49 PM
Yup! but with the aid of the planets revolution at its centre linking P.V. to ocean surface?
Title: Re: The 2017 Melting Season
Post by: bbr2314 on January 10, 2017, 05:17:31 PM
Yup! but with the aid of the planets revolution at its centre linking P.V. to ocean surface?
I think you are onto something --

It should also be noted while high-latitude cyclones often attain very low pressures, I do not believe that ever happens *this* far north. It has become increasingly common in the southern areas of the Bering & Barents/Kara but in the actual Arctic Ocean we did not see events like ^ in any of the recent summers or winters from what I can recall.
Title: Re: The 2017 Melting Season
Post by: Iceismylife on January 10, 2017, 05:53:07 PM
I wonder if you can see a 'cold core' Hurricane?

 I mean if the sea ice is smashed up and the 'relatively' warm, moist, air flowing out of those leads fueling convection in the arctic air above? As the storm grew it would smash more ice /wash up more heat to the surface and so on as it sat over the pole........

A bit 'day after Tomorrow' really but if it's all about the relative sea surface temp to air above a wide enough disrupted ice zone might provide enough heat/moisture to set up unfettered convection?
I started a thread asking just about this question this fall. Any answers?
Title: Re: The 2017 Melting Season
Post by: Neven on January 10, 2017, 07:50:22 PM
People, seriously, the melting season has not started. All your comments belong in this thread (http://forum.arctic-sea-ice.net/index.php/topic,1611.msg98753.html#msg98753). I'm locking this one until March/April.
Title: Re: The 2017 Melting Season
Post by: Neven on February 23, 2017, 09:21:10 AM
Kick.
Title: Re: The 2017 melting season
Post by: Gray-Wolf on February 23, 2017, 09:32:34 AM
I wondered ,once Mr Hunt had ummed and arred about whether we could be seeing max being reached, how long before we got the thread! :)
Title: Re: The 2017 melting season
Post by: 5to10 on February 23, 2017, 09:46:28 AM
If it goes ice free this year and there's nothing stopping all that water from absorbing heat... what next? This is worrisome.. Is this, for all intents and purposes, the final/one of the final melt seasons?
Title: Re: The 2017 melting season
Post by: DoomInTheUK on February 23, 2017, 09:49:40 AM
Well if re-opening a melting thread in Feb ends up as being the weirdest thing about this melt season then I think we'll get off quite lightly.

Personally I still blame Neven. He took a few weeks off and it's never been the same since.  ::)
Title: Re: The 2017 melting season
Post by: oren on February 23, 2017, 11:38:04 AM
If it goes ice free this year and there's nothing stopping all that water from absorbing heat... what next? This is worrisome.. Is this, for all intents and purposes, the final/one of the final melt seasons?
Please remember that if it does go ice free this year, it will do so with two caveats:
Ice free will not mean totally ice free, not this year. A lot of ice will still remain north of the CAA and Greenland. So 1 million km2 of ice still stops a lot of water from absorbing heat.
In addition, ice free will not mean at peak insolation time, but most probably in early September. At that period it is mostly the heat in the water, and the storms, that finish the job. So the temps in central CAB will not have time to rise very much given the expected season trajectory as I see it.

On the other hand, peripheral CAB-adjacent seas such as the Chukchi, Barents with its nearby CAB sector, and Beaufort (assuming it does open up early and has a total meltout as I expect) could see big temp spikes in late summer, with dire consequences for the CAB ice.

As to whether this is the final melting season, have no fear. Ice in midwinter in the CAB will still freeze, even if very late and much thinner than in the past. Disclosure: some on the forum expect otherwise.
Title: Re: The 2017 melting season
Post by: Tigertown on February 23, 2017, 01:24:37 PM
I don't think everything has to be in such absolutes. More open water earlier in the season simply means more problems for later this season, which carry over into the freezing season. Those carry over into the following year. Ironically, it is called a snowball effect. At some point the least of our worries will be SIE.

P.S. I guess that I should have posted this here instead of the freezing season thread.
I am not trying to start a conversation about it here, as we have a thread for it, but just so everyone knows; the PV has split and will soon start to weaken. The positive temp. anomalies will start to creep back into the Arctic, just as the forecast shows.
Title: Re: The 2017 melting season
Post by: Archimid on February 23, 2017, 02:29:50 PM
I think that 20 years ago the distinction of the melting season and the freezing season was obvious and easy to make out. During the freezing season ice would almost monotonically grow and during the melting season ice will monotonically melt. As the Arctic warms this distinction is becoming less obvious. I think it is almost to a point that a season between the freezing and melting season can be justified.

Title: Re: The 2017 melting season
Post by: gerontocrat on February 23, 2017, 03:17:08 PM
I am having an argument with myself -

It is NOT the melting season, dumbo. Sea ice volume is increasing.
It IS the melting season, you fool. Look at the flood of beaten up ice coming down the Fram, the PV giving up the ghost etc etc etc.

But it is a fruitless argument, since both melting and freezing are happening. Surely what matters are how rapid the periphery will melt (insolation) and the timing and km3 000 of the sea ice volume maximum ? This additional data will inform the debate on what happens next and when.
Title: Re: The 2017 melting season
Post by: Archimid on February 23, 2017, 03:43:53 PM

It is NOT the melting season, dumbo. Sea ice volume is increasing.


Great point. Volume is increasing and historically it increases until April. So by volume the melting season starts in April but by extent the melting season starts in early March.
Title: Re: The 2017 melting season
Post by: magnamentis on February 23, 2017, 03:54:28 PM
If it goes ice free this year and there's nothing stopping all that water from absorbing heat... what next? This is worrisome.. Is this, for all intents and purposes, the final/one of the final melt seasons?

please keep in mind that even once it goes ice-free (for me ice-free is around zero and not around 1M km2) that will not get us rid of a melting season because ice free refers to summer and not to "all year round"

if a an all year ice free arctic will ever happen which i doubt for a few centuries or more, discussion will long have moved to Sea Level Rise and other more important things than SIE & SIE.

generally it's always recommended to not overshoot in wording so not to feed the trolls and the deniers with easily deniable "fodder"
Title: Re: The 2017 melting season
Post by: Gray-Wolf on February 23, 2017, 05:27:11 PM
Looking at the ice now visible from the MODIS sats you can see just how poor the ice is! Where two leads meet the ice between is shattered rubble, no clean edges of yesteryear this ice just collapses back into the rubble we last saw in Sept. I just do not know how this will act under full sun? I imagine any late formed FY ice 'glue' that holds the pack together would be the first thing to go but how solid is the older ice? How many times have the larger floes already been fragmented and 'glued ' back together?

https://worldview.earthdata.nasa.gov/?p=arctic&l=VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor,Reference_Labels(hidden),Reference_Features(hidden),Coastlines&t=2017-02-23&z=3&v=-1650176,1150848,-1475328,1232512

above are a couple of leads in the west of Beaufort ( toward Bering) showing this rubble zone where they meet/join.
Title: Re: The 2017 melting season
Post by: 5to10 on February 23, 2017, 06:08:21 PM
I don't see how ice can reform anywhere near even the last freeze season once it's open ocean. Too much warming too quickly over the months following, no? I don't understand the physics of it. Shouldn't that be a huge tipping point? How does it jump back out of "essentially ice free" once it gets there?

I really don't understand this, but I'm not educated enough to. Where exactly do the cold temperatures required to refreeze substantially come from after all the ice is gone? Isn't all that ice floating there an inherent necessity to reach and maintain such temperatures? Doesn't it directly influence air/water surface temps and such?

So how does it have any chance of refreezing after essentially total melt, to anywhere near "where it should" (where we desperately want it to)?
Title: Re: The 2017 melting season
Post by: 5to10 on February 23, 2017, 06:12:43 PM
I suppose I'm viewing the ice as sort of a buffer.. I see it as kind of a chicken/egg scenario. To some extent, to put it roughly, it's cold because there's ice, there's ice because it's cold, this system was well maintained for quite some time.

Now what? Is that just a faulty perspective?

I guess a better question would be.. Is the arctic in general warming at the same rate or a faster rate than the global average? If it's warming at a faster rate, isn't that directly correlated to the amount of receding ice (and all the positive feedbacks that creates)? As in, it would be warming a little bit faster because the ice itself helps regulate temperature.. Does the possibility of hitting such low temperatures heavily decrease or disappear with the ice?

Sorry in advance if this is all nonsense or common knowledge. I just can't fathom how, once the ice is more or less gone, it reforms to any great degree.
Title: Re: The 2017 melting season
Post by: Tigertown on February 23, 2017, 06:28:31 PM
The idea is that it gets so cold in the Arctic when the sun is not up, that nothing else matters. There are starting to appear to be more and more reasons for that not to be true. One thing being the breakdown of the inversion layer.              http://forum.arctic-sea-ice.net/index.php/topic,1885.msg104326/topicseen.html#msg104326
Personally, I think there is enough ice now and that it will take long enough to melt this year so as to have one more screwed up freezing season. However, by next year, when the melt out comes so early in the year, the waters will simply absorb too much energy for there to be a freezing season.


There may be a better thread for this line of thought if it continues to be the focus. Better some of us move it than to burden Neven.
Title: Re: The 2017 melting season
Post by: P-maker on February 23, 2017, 08:04:55 PM
Gents,

Allow me to intervene in your discussion. The way to define abrupt climate change is not clear at all, but I sense that you will all appreciate that these statements have been made recently in various threads here:

1)   “1C increase a year for 5 straight years, then it levels off for a few years only to rise later by another series of 1C a year for 5 years for a total of 10C!”
2) “some on the forum expect otherwise.”
3)  “A cliff is the right analogy for a range of reasons. Perhaps most starkly it’s climate change…”
4) ” I guess that I should have posted this here instead of the freezing season thread.”
5) " There may be a better thread for this line of thought..."

Having such difficulties defining whether we are falling off a cliff, whether we are in the freezing or melting season and whether poor freezing may lead to rapid melting, I think it is time to get our act together,

By getting our act together, I mean that we should all accept that we are here trying to make a coherent and collaborative risk assessment regarding the ultimate loss of Arctic sea ice. Should we lose it this autumn, we all know that it could potentially be gone forever. Permanent. Full stop. Lost!

Hence I would suggest a new unifying thread under the label: Towards an ice-free 2017. In case we do not reach this state before Christmas, there will be an opportunity to open up a similar 2018 thread.

Such a thread could unite both the various freezing and melting threads. It could include the somewhat speculative “Ice-free Arctic” thread as well as the “Arctic temperature layers and inversions” thread. Sometimes it helps to bring thoughts together.

I would like to see a slower pace here, deeper thoughts, fewer and better links and more reflection. Keeping up with all the valid contributions to this forum is a nearly 24/7 job. No wonder Neven is getting tired. So are the rest of us trying to catch up on North American and Australian contributions, when we wake up in the morning.

It is time to focus, communicate clearly and not get lost in details.
Title: Re: The 2017 melting season
Post by: 5to10 on February 23, 2017, 08:18:19 PM
Gents,

Allow me to intervene in your discussion. The way to define abrupt climate change is not clear at all, but I sense that you will all appreciate that these statements have been made recently in various threads here:

1)   “1C increase a year for 5 straight years, then it levels off for a few years only to rise later by another series of 1C a year for 5 years for a total of 10C!”
2) “some on the forum expect otherwise.”
3)  “A cliff is the right analogy for a range of reasons. Perhaps most starkly it’s climate change…”
4) ” I guess that I should have posted this here instead of the freezing season thread.”
5) " There may be a better thread for this line of thought..."

Having such difficulties defining whether we are falling off a cliff, whether we are in the freezing or melting season and whether poor freezing may lead to rapid melting, I think it is time to get our act together,

By getting our act together, I mean that we should all accept that we are here trying to make a coherent and collaborative risk assessment regarding the ultimate loss of Arctic sea ice. Should we lose it this autumn, we all know that it could potentially be gone forever. Permanent. Full stop. Lost!

Hence I would suggest a new unifying thread under the label: Towards an ice-free 2017. In case we do not reach this state before Christmas, there will be an opportunity to open up a similar 2018 thread.

Such a thread could unite both the various freezing and melting threads. It could include the somewhat speculative “Ice-free Arctic” thread as well as the “Arctic temperature layers and inversions” thread. Sometimes it helps to bring thoughts together.

I would like to see a slower pace here, deeper thoughts, fewer and better links and more reflection. Keeping up with all the valid contributions to this forum is a nearly 24/7 job. No wonder Neven is getting tired. So are the rest of us trying to catch up on North American and Australian contributions, when we wake up in the morning.

It is time to focus, communicate clearly and not get lost in details.

I agree, sorry for contributing to bogging this thread up but I can't seem to find anywhere existing to discuss these ideas without being offtopic. It seems like you say that the sooner the better.

From a laymans perspective, I feel like there are a lot of great minds on this forum discussing the fine details and a ton of great information is here regarding them, but I have yet to see something like a concerted work towards a more accurate model of what's going on - incorporating as many known feedbacks above a certain threshold of influence as we know of. Surely it would give a better indicator than published models which fail to account for all of them.

Even if you all started ballparking a timeframe together, or what will happen this melt season, how it will re-freeze.. But I think there is a bit of a fear to do that not just because it doesn't precisely follow scientific method (But there are kind of too many variables to do that accurately, so perhaps throwing that out the window to a degree, i.e. submission for peer review, is in order given the circumstances..), but of a gut feeling of how bad the results will be...
Title: Re: The 2017 melting season
Post by: Tigertown on February 23, 2017, 08:33:08 PM
There is a thread for this topic that has a lot of leeway in it.
http://forum.arctic-sea-ice.net/index.php/topic,1886.msg104343/topicseen.html#msg104343
Title: Re: The 2017 melting season
Post by: georged on February 24, 2017, 01:11:17 AM
What's the evidence that we've reached an annual peak? This thread seems about three or four weeks too early.
Title: Re: The 2017 melting season
Post by: magnamentis on February 24, 2017, 01:16:00 AM
I don't see how ice can reform anywhere near even the last freeze season once it's open ocean. Too much warming too quickly over the months following, no? I don't understand the physics of it. Shouldn't that be a huge tipping point? How does it jump back out of "essentially ice free" once it gets there?

I really don't understand this, but I'm not educated enough to. Where exactly do the cold temperatures required to refreeze substantially come from after all the ice is gone? Isn't all that ice floating there an inherent necessity to reach and maintain such temperatures? Doesn't it directly influence air/water surface temps and such?

So how does it have any chance of refreezing after essentially total melt, to anywhere near "where it should" (where we desperately want it to)?

in cold winters where temps are between -10 to -20C for a week or two ice forms even very far south.

even though temps are nowadays very high for arctic standards, they are still mostly between -10 and -30C and hence the ocean will freeze over like any other waters, in parts much farther south do, once it's getting long enough cold enough, which both will be the case for many many years to come in the central arctic. keep in mind that we see frozen ocean where the water in summer is often around 5C in places up to 15C like i.e. "ostsee" and still they can freeze over if temps and time span are bouth favourable.

in short, IMO your assumption is wrong, simple as that.
Title: Re: The 2017 melting season
Post by: 5to10 on February 24, 2017, 01:41:27 AM
I don't see how ice can reform anywhere near even the last freeze season once it's open ocean. Too much warming too quickly over the months following, no? I don't understand the physics of it. Shouldn't that be a huge tipping point? How does it jump back out of "essentially ice free" once it gets there?

I really don't understand this, but I'm not educated enough to. Where exactly do the cold temperatures required to refreeze substantially come from after all the ice is gone? Isn't all that ice floating there an inherent necessity to reach and maintain such temperatures? Doesn't it directly influence air/water surface temps and such?

So how does it have any chance of refreezing after essentially total melt, to anywhere near "where it should" (where we desperately want it to)?

in cold winters where temps are between -10 to -20C for a week or two ice forms even very far south.

even though temps are nowadays very high for arctic standards, they are still mostly between -10 and -30C and hence the ocean will freeze over like any other waters, in parts much farther south do, once it's getting long enough cold enough, which both will be the case for many many years to come in the central arctic. keep in mind that we see frozen ocean where the water in summer is often around 5C in places up to 15C like i.e. "ostsee" and still they can freeze over if temps and time span are bouth favourable.

in short, IMO your assumption is wrong, simple as that.

I really hope it is, thank you.
Title: Re: The 2017 melting season
Post by: Pmt111500 on February 24, 2017, 01:49:52 AM
What's the evidence that we've reached an annual peak? This thread seems about three or four weeks too early.
Technically, Arctic has no fixed boundary so some could nitpick there's always some melt going on... But yes there's no evidence the ice growth would have stopped already. I'd like to see the 15-day average of Ice Area turn down before saying it's definitely melt season. I'm okay by having this thread open already, but thickness growth continues on several areas still. Heck, even us here at 60.27°N got some 10cm snow just a day ago. Now the snow is about thickest this winter, maybe even 12cm (~ 4 3/4 inches). Official measurement site says 7 but what do they know. Mental.
Title: Re: The 2017 melting season
Post by: jai mitchell on February 24, 2017, 06:21:21 AM
 :o too soon  :o
Title: Re: The 2017 melting season
Post by: bairgon on February 24, 2017, 09:00:05 AM
I'm inexperienced at this, as it is my first melt season on the forum. However, I've observed significant drops in extent when the wind is blowing onto the ice with warm air and presumably waves. There is still a notch out of the ice near Newfoundland because of a recent event - see this message:

Nullshcool is showing a low tracking up that eastern Canadian coast from 14th to 16th, with warm onshore winds followed by offshore. Looks like that will damage the ice in the same way as the recent damage to Fram.

Looking at Nullschool there is significant warm air coming up into the Bering Strait on Saturday; followed by consistent warm onshore winds on the eastern Canadian coast on Sunday through Monday.

My guess is that these will cause extent to drop, perhaps firming up the maximum.
Title: Re: The 2017 melting season
Post by: Darvince on February 24, 2017, 09:23:56 AM
is often around 5C in places up to 15C like i.e. "ostsee" and still they can freeze over if temps and time span are bouth favourable.
Baltic Sea in English. ;)

And in Liaoning Bay in China, which reaches temperatures warm enough for tropical cyclones in the heat of the summer, 26C, there are small amounts of gray ice this time of year.
Title: Re: The 2017 melting season
Post by: Jim Williams on February 24, 2017, 04:51:20 PM
Rather than speculating on whether it has or has not started, maybe we should be thinking about what tools people with various levels can use to monitor the (coming) season.

I suggest for people who are fairly new to watching the seasons world-wide, or who like me simply need an occasional reminder, that a map of day and night such as this can be useful:

https://www.timeanddate.com/worldclock/sunearth.html (https://www.timeanddate.com/worldclock/sunearth.html)
Title: Re: The 2017 melting season
Post by: magnamentis on February 25, 2017, 01:24:24 AM
is often around 5C in places up to 15C like i.e. "ostsee" and still they can freeze over if temps and time span are bouth favourable.
Baltic Sea in English. ;)

And in Liaoning Bay in China, which reaches temperatures warm enough for tropical cyclones in the heat of the summer, 26C, there are small amounts of gray ice this time of year.

baltic, right, thanks, i should have looked it up but was a bit in a hurry :-) nice that you jumped in

cheers
Title: Re: The 2017 melting season
Post by: Tigertown on February 25, 2017, 06:04:28 AM
Just noticed extent, both NSIDC and JAXA, have gone down. But for anyone who had any doubt about melt season beginning, check out the volume drop. ;)
(http://)
Title: Re: The 2017 melting season
Post by: Pmt111500 on February 25, 2017, 06:14:03 AM
Just noticed extent, both NSIDC and JAXA, have gone down. But for anyone who had any doubt about melt season beginning, check out the volume drop. ;)
(http://)
Oh, that looks like an adjustment made by Pruitt :D .


Title: Re: The 2017 melting season
Post by: Dave C on February 25, 2017, 09:05:28 AM
Just noticed extent, both NSIDC and JAXA, have gone down. But for anyone who had any doubt about melt season beginning, check out the volume drop. ;)

I've always thought it is funny that groups would post these results.
Would it really be worse to wait a day or two to check the numbers for absurdity?
Title: Re: The 2017 melting season
Post by: Neven on February 25, 2017, 01:09:04 PM
Would it really be worse to wait a day or two to check the numbers for absurdity?

Yes, it would be. We want near-real time numbers, and we all understand that sometimes things go wrong with automated processes. That's why we - unlike climate risk deniers - don't make a fuss about it when it happens.

BTW, I'm visiting relatives in the Netherlands this week, so won't be able to perform near-real time moderating activities (but I try to read up in the mornings and evenings). Just so you know.

And for me the melting season officially starts when (JAXA) extent has reached its maximum. That to me is sort of a tradition. Even though volume will continue to grow for a few weeks longer. But it's not that important.
Title: Re: The 2017 melting season
Post by: bairgon on February 25, 2017, 01:42:40 PM
The CAA garlic press has been mentioned a few times.

I've been watching the live MODIS true colour images of the Barrow Strait past Resolute, Canada (with Griffith Island - I was born in Griffith, NSW). The ice has been slumping regularly - see gif below which is from 19th to 24th Feb.

I checked back through previous years and there is nothing that matches this so early in the season.

The most recent date in the gif can be seen at https://worldview.earthdata.nasa.gov/?p=arctic&l=VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor,Reference_Labels(hidden),Reference_Features(hidden),Coastlines&t=2017-02-24&z=3&v=-1660863.4345131656,-1463410.123253129,-677823.4345131656,-959090.123253129&ab=on&as=2017-02-19&ae=2017-02-24&av=1&al=false (https://worldview.earthdata.nasa.gov/?p=arctic&l=VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor,Reference_Labels(hidden),Reference_Features(hidden),Coastlines&t=2017-02-24&z=3&v=-1660863.4345131656,-1463410.123253129,-677823.4345131656,-959090.123253129&ab=on&as=2017-02-19&ae=2017-02-24&av=1&al=false)

Title: Re: The 2017 melting season
Post by: Tigertown on February 25, 2017, 04:09:35 PM
It is fixed by the way, in case anyone didn't catch the  ;) to start with, which was supposed to be a hint that it was not real. As if.    P.S. NSIDC extent really dropped again, though.
(http://)
Title: Re: The 2017 melting season
Post by: pauldry600 on February 25, 2017, 04:35:33 PM
I was looking at world view last night and the weakness of the ice is staggering, just staggering. Ive been studying the arctic since 2005 and what I am seeing at the moment is ice Ive seen previously in June. This to me looks a year that could see a very very small minimum but ill pass judgement later in the year. Maybe theres going to be a miracle or some 50bn sea ice generators
Title: Re: The 2017 melting season
Post by: peterlvmeng on February 25, 2017, 05:17:54 PM
It is fixed by the way, in case anyone didn't catch the  ;) to start with, which was supposed to be a hint that it was not real. As if.    P.S. NSIDC extent really dropped again, though.
(http://)

Maybe the thickness is increasing dramatically.
Title: Re: The 2017 melting season
Post by: romett1 on February 25, 2017, 06:37:16 PM
I was looking at world view last night and the weakness of the ice is staggering, just staggering. Ive been studying the arctic since 2005 and what I am seeing at the moment is ice Ive seen previously in June. This to me looks a year that could see a very very small minimum but ill pass judgement later in the year. Maybe theres going to be a miracle or some 50bn sea ice generators

Hycom confirms, it's staggering. Needs to be clicked. Compared Feb 24 this year vs 2016. Look at Laptev Sea, ESS and Beaufort. And all the thickest ice near Fram Strait for export. Also positive anomalies (+1.1 - +2.0 C) for Arctic Feb 26 - Mar 4 (Climate Reanalyzer). Images from https://www7320.nrlssc.navy.mil/hycomARC/arctic.html
Title: Re: The 2017 melting season
Post by: Tigertown on February 25, 2017, 07:32:38 PM
That was a nice little run we had there for a few days, but now reality has to set back in.
 Feb. 20th comp'ed to Feb. 24th
CLICK IMAGE PLEASE
(http://)
Title: Re: The 2017 melting season
Post by: Pavel on February 25, 2017, 09:01:38 PM
Maybe I'm once again impatient, but the weather conditions in the Barents and the Sea of Okhotsk in several days may cause SIE to drop significantly in those seas. The SoO is located between 44 and 61 latitudes, so the insolation is high already especially in the south. On the other hand SIE can rise in the Barents sea. Anyway SIE is near it's annual maximum and it's possible the melting season have already started in terms of SIE
Title: Re: The 2017 melting season
Post by: Shared Humanity on February 25, 2017, 09:34:23 PM
Just noticed extent, both NSIDC and JAXA, have gone down. But for anyone who had any doubt about melt season beginning, check out the volume drop. ;)

I've always thought it is funny that groups would post these results.
Would it really be worse to wait a day or two to check the numbers for absurdity?

And miss the opportunity to lighten the mood of the community in the midst of this Greek Tragedy?  ???
Title: Re: The 2017 melting season
Post by: Shared Humanity on February 25, 2017, 09:36:43 PM
I was looking at world view last night and the weakness of the ice is staggering, just staggering. Ive been studying the arctic since 2005 and what I am seeing at the moment is ice Ive seen previously in June. This to me looks a year that could see a very very small minimum but ill pass judgement later in the year. Maybe theres going to be a miracle or some 50bn sea ice generators

Hycom confirms, it's staggering. Needs to be clicked. Compared Feb 24 this year vs 2016. Look at Laptev Sea, ESS and Beaufort. And all the thickest ice near Fram Strait for export. Also positive anomalies (+1.1 - +2.0 C) for Arctic Feb 26 - Mar 4 (Climate Reanalyzer). Images from https://www7320.nrlssc.navy.mil/hycomARC/arctic.html

And we must keep in mind that, despite all of the very thick ice in the Beaufort last year, it melted out completely. This melt season will be riveting.
Title: Re: The 2017 melting season
Post by: Tigertown on February 26, 2017, 08:40:13 AM
Very strong and persistent winds in and around the Arctic for the next several days. With much of the ice so thin, the drifting and movement will continue to cause melt. The air and winds are very cold, but this just doesn't help much when warm waters keep getting stirred up.
Title: Re: The 2017 melting season
Post by: Lord M Vader on February 26, 2017, 10:29:48 AM
A very important question is how thick the snow cover is right now onto the ice after all those bomb cyclones during most of this freezing season?

From this article at InsideClimatenews.org that looks at the sea ice paradox wrt to ice growth around Antarctica and melting Arctic. In the article there is an important statement which might have big implications for the upcoming melting season:

"Additionally, the snowpack on top of the Antarctic ice is much thicker than in the Arctic, Nicolaus said. That means there is less formation of dark-colored surface melt ponds, which amplify the melting and warming in the Arctic, he explained."

Now, is the snow cover thicker compared to 2013 and other years?

Read more at https://insideclimatenews.org/news/31052016/why-antarctica-sea-ice-level-growing-while-arctic-glaciers-melts-climate-change-global-warming (https://insideclimatenews.org/news/31052016/why-antarctica-sea-ice-level-growing-while-arctic-glaciers-melts-climate-change-global-warming)
Title: Re: The 2017 melting season
Post by: Dave C on February 26, 2017, 02:53:28 PM
Would it really be worse to wait a day or two to check the numbers for absurdity?

Yes, it would be. We want near-real time numbers, and we all understand that sometimes things go wrong with automated processes. That's why we - unlike climate risk deniers - don't make a fuss about it when it happens.


I would strongly disagree. Credibility is extremely important if you are producing information. Humans tend to think in heuristics, rather than extensively verify every piece of data. If someone produces obviously wrong data it's reasonable to be concerned that they are making other more subtle errors that are not being corrected. I think trust in your numbers is much more important than the convenience of real time data.
Title: Re: The 2017 melting season
Post by: magnamentis on February 26, 2017, 04:36:42 PM
Would it really be worse to wait a day or two to check the numbers for absurdity?

Yes, it would be. We want near-real time numbers, and we all understand that sometimes things go wrong with automated processes. That's why we - unlike climate risk deniers - don't make a fuss about it when it happens.


I would strongly disagree. Credibility is extremely important if you are producing information. Humans tend to think in heuristics, rather than extensively verify every piece of data. If someone produces obviously wrong data it's reasonable to be concerned that they are making other more subtle errors that are not being corrected. I think trust in your numbers is much more important than the convenience of real time data.

thanks, has been my point for long, just that quite often someone feels offended due to connections to specific work or having friends that are related and as a rusult feedback can be quite harsh out of the blue at times LOL.

anyways i'm very glad that others as well are aware that no information at all, is better than wrong information while of course in this clear case one could say it's obvious, but believe me, i have been reading deniers comments on obvious flukes that made me speechless, hence we are back to rule number one, the truth and nothing but the truth to achieve and keep the highest possible level of credibility. ultimately deniers re-plenish their arsenal from mistakes of those in defense of the just cause.
Title: Re: The 2017 melting season
Post by: dnem on February 26, 2017, 07:28:27 PM
C'mon folks, TT's post was just a little joke complete with a wink emoji.  Let's not get too serious here (the situation itself is serious enough!).
Title: Re: The 2017 melting season
Post by: magnamentis on February 26, 2017, 10:12:10 PM
C'mon folks, TT's post was just a little joke complete with a wink emoji.  Let's not get too serious here (the situation itself is serious enough!).

no problem while at times a joke can trigger a serious discussion and the subject is very very important if we want to get an impact with our contributions and for example with this forum, hence i can see nothing wrong with the discussion except that it would belong to another thread should it continue.

i do not disagree but why do you care so much about that little exchange, frankly speaking it was positive and fun and not the fun is gone for no good reason. i think the remark was not helpful but that's my opinion and no offense meant.
Title: Re: The 2017 melting season
Post by: Tigertown on February 27, 2017, 06:49:24 AM
Undeniable melting in the Bering.
24th thru 26th
CLICK IMAGE PLEASE
Title: Re: The 2017 melting season
Post by: JayW on February 27, 2017, 07:35:27 AM
Feb 23-26. VIIRS I05 band from the University of Alaska at Fairbanks

Hints of the Beaufort gyre?  I find it difficult to believe we see anything analogous to the "big block" this year.


http://feeder.gina.alaska.edu (http://feeder.gina.alaska.edu)
Title: Re: The 2017 melting season
Post by: Tigertown on February 27, 2017, 10:02:30 PM
NSIDC SIE  106 km2

2017,    02,  16,     14.301

2017,    02,  26,     14.325

10 days net increase approx. 24k
Title: Re: The 2017 melting season
Post by: Tigertown on February 28, 2017, 05:43:27 AM
Another JAXA SIE drop today. Volume is currently stymied, the PV is split and weakened, and the temp. anomalies are slowly returning to the Arctic. Here is a look at SMOS.
(http://)
Title: Re: The 2017 melting season
Post by: jdallen on February 28, 2017, 06:30:43 AM
Another JAXA SIE drop today. Volume is currently stymied, the PV is split and weakened, and the temp. anomalies are slowly returning to the Arctic. ...
We don't need the anomalies any more.  We are less than 4 weeks from the equinox.  Insolation in the peripheral seas pretty much is putting paid on the Max, and is already starting to shift the dynamic away from creating more ice.  Get ready for the drop.
Title: Re: The 2017 melting season
Post by: Tigertown on February 28, 2017, 06:33:00 AM
Another JAXA SIE drop today. Volume is currently stymied, the PV is split and weakened, and the temp. anomalies are slowly returning to the Arctic. ...
We don't need the anomalies any more.  We are less than 4 weeks from the equinox.  Insolation in the peripheral seas pretty much is putting paid on the Max, and is already starting to shift the dynamic away from creating more ice.  Get ready for the drop.
Good point.
Title: Re: The 2017 melting season
Post by: Glenn Tamblyn on February 28, 2017, 07:15:45 AM
Particularly with those low thicknesses in the Sea of Okhostk. Mucho Biggo extent decline ready to go there to kick off the season.
Title: Re: The 2017 melting season
Post by: wallen on February 28, 2017, 09:09:21 AM
With the coming melt season, I was wondering what effect Melt Ponds will have this year, or is the ice condition already so poor, that Melt Ponds will not be required for any pre-conditioning .
Title: Re: The 2017 melting season
Post by: Gray-Wolf on February 28, 2017, 09:46:54 AM
Hi wallen!

I think the glory days of the melt pond are lost? The 'crackopalypse years' lead to a reduction in floe size so the large expanses of melt water covering sections of the pack just cannot form up any more without draining due to leads?

The new measure should be those lead densities? Leads also darken the overall surface. If the floe is small enough then side melt becomes a major cause of melt out so many sub 100m floes means early and rapid melt?

I'm sure other think differently though! :)
Title: Re: The 2017 melting season
Post by: Jim Hunt on February 28, 2017, 10:25:13 AM
The Barrow Strait looking somewhat the worse for wear:

http://GreatWhiteCon.info/resources/arctic-sea-ice-images/winter-201617-images/#CAA (http://GreatWhiteCon.info/resources/arctic-sea-ice-images/winter-201617-images/#CAA)

Title: Re: The 2017 melting season
Post by: Shared Humanity on February 28, 2017, 03:51:54 PM
I think the Northwest Passage will open very early this year, perhaps the earliest on record. The only possible problem could be the reemergence of the "Garlic Press" with thick MYI traversing the CAA and blocking the passage.
Title: Re: The 2017 melting season
Post by: bairgon on February 28, 2017, 05:04:28 PM
thick MYI

Precious little of that around...
Title: Re: The 2017 melting season
Post by: magnamentis on February 28, 2017, 08:00:37 PM
With the coming melt season, I was wondering what effect Melt Ponds will have this year, or is the ice condition already so poor, that Melt Ponds will not be required for any pre-conditioning .

i think there will be only few ponds because the smallest poodle immediatly will break through to the ocean surface, partly kidding but i expect at least a bit of this.
Title: Re: The 2017 melting season
Post by: Shared Humanity on February 28, 2017, 10:35:45 PM
thick MYI

Precious little of that around...

Much of it moved into the CAA last year. You can find it in channels between the islands.
Title: Re: The 2017 melting season
Post by: Tigertown on March 01, 2017, 04:29:26 AM
A revisit of the concentration, with the image for the 28th double-timed.
CLICK IMAGE PLEASE
(http://)
Title: Re: The 2017 melting season
Post by: Tigertown on March 01, 2017, 04:45:03 AM
Temp. anomalies may not be needed to have melting anymore at this point in the year, but we have them nonetheless. Just a visual inspection of the concentration that I posted above shows how the ice is going down again. I am afraid of what will happen with some real heat and insolation later this year. Talk about preconditioning.
(http://)
Title: Re: The 2017 melting season
Post by: romett1 on March 01, 2017, 11:05:14 AM
Temp. anomalies may not be needed to have melting anymore at this point in the year, but we have them nonetheless. Just a visual inspection of the concentration that I posted above shows how the ice is going down again. I am afraid of what will happen with some real heat and insolation later this year. Talk about preconditioning.
(http://)

ESS area seems to be much warmer than average Mar 3 - Mar 9.
On the other hand extremely cold over Alaska and Northern Canada.
Title: Re: The 2017 melting season
Post by: Red on March 01, 2017, 04:21:46 PM
Looking at the satellite shot for the 27th there is open water forming on the west coast of Ungava Bay and along the northeast coast of Labrador. There seems to be lots of room for compaction in the Davis Strait.
 https://worldview.earthdata.nasa.gov/?p=arctic&l=MODIS_Aqua_CorrectedReflectance_TrueColor,MODIS_Terra_CorrectedReflectance_TrueColor,Coastlines,Reference_Labels(hidden),Reference_Features(hidden)&t=2017-02-27&z=3&v=-1459701.7703771119,-3268899.3955504056,-927733.7703771119,-2925859.3955504056
 Then when looking at the movement of the ice off of Labrador, Nullschool is showing sea surface temps just east of the ice pack at 4c. Is this enough to keep the the ice flowing freely out of the stait so as to keep the garlic press exit from clogging? 4c would probably work some magic on the slushy that is the ice pack?

https://earth.nullschool.net/#current/ocean/primary/waves/overlay=sea_surface_temp/orthographic=-67.77,58.16,2849/loc=-57.803,58.520
Title: Re: The 2017 melting season
Post by: bairgon on March 01, 2017, 05:34:08 PM
Looking at the satellite shot for the 27th there is open water forming on the west coast of Ungava Bay and along the northeast coast of Labrador.

Looking further south from your link, you can see how the ice has been separated from the land and pushed south (look for features that match). There was strong off-shore winds in that period.

However, the winds are forecast to strengthen to on-shore with a significant northerly component, and temperatures increasing, so I expect the ice to be decimated in this area.
Title: Re: The 2017 melting season
Post by: Cate on March 01, 2017, 09:07:11 PM
And farther south again, on the NE coast of Newfoundland, the Canadian Ice Service chart for Feb 28 shows some lessening of pressure, with concentration close to shore dropping to 7-8/10, down from 9-10/10 last week. Most likely this is a function of offshore winds, as bairgon has noted. Bonavista Bay has also cleared out---for now, of course. A change in wind can bring it all back in. The ice in this area--the traditional "front" for the Newfoundland seal hunt----is almost entirely wind-dependent. Melt-out is a matter of when, not if. This is the time of year when we Newfoundlanders start to pray for sustained sou'westerlies, to blow the damned stuff back out into the Labrador Current and on south to warmer waters.
Title: Re: The 2017 melting season
Post by: romett1 on March 03, 2017, 07:42:03 PM
I was looking recent Climate Reanalyzer, it's going to be warm Mar 8 - Mar 11, in some places anomalies +20 - +30 ˚C (ESS, Chukchi Sea, Beaufort Sea and Baffin Bay). Fram export will be active again Mar 5 - Mar 7 according to Hycom.
Title: Re: The 2017 melting season
Post by: romett1 on March 04, 2017, 06:59:06 PM
Latest Hycom shows Fram export accelerating Mar 8 - Mar 11. Images from: https://www7320.nrlssc.navy.mil/hycomARC/arctic.html
Title: Re: The 2017 melting season
Post by: Shared Humanity on March 04, 2017, 11:05:49 PM
Beaufort has thickened a bit over the past few weeks.
Title: Re: The 2017 melting season
Post by: jdallen on March 05, 2017, 01:24:09 AM
Beaufort has thickened a bit over the past few weeks.
Hard for it not to, as a lot of the ice was well under 1.5M...
Title: Re: The 2017 melting season
Post by: Archimid on March 05, 2017, 05:55:45 PM
Using nullschool, the following images are the Pacific Ocean Sea Surface Temperature Anomalies for 5 March 2015,2016,2017

I think the North Pacific is much cooler this year and that might favor a milder melting season.

Title: Re: The 2017 melting season
Post by: romett1 on March 05, 2017, 07:38:39 PM
As A-Team is missing, I try to operate with gif's. Latest Hycom forecast Mar 8 - Mar 12. Notice Fram export, Bering Strait and Chukchi Sea. Images from: https://www7320.nrlssc.navy.mil/hycomARC/arctic.html
Title: Re: The 2017 melting season
Post by: Tigertown on March 05, 2017, 08:03:44 PM
Using nullschool, the following images are the Pacific Ocean Sea Surface Temperature Anomalies for 5 March 2015,2016,2017

I think the North Pacific is much cooler this year and that might favor a milder melting season.
You might want to look at a site that gives temps. just below the surface. Storms tend to cool the surface fairly quick.
(http://)
Title: Re: The 2017 melting season
Post by: jdallen on March 05, 2017, 08:37:42 PM
As A-Team is missing, I try to operate with gif's. Latest Hycom forecast Mar 8 - Mar 12. Notice Fram export, Bering Strait and Chukchi Sea. Images from: https://www7320.nrlssc.navy.mil/hycomARC/arctic.html
Notice also, not a lot of thickening, anywhere.
Title: Re: The 2017 melting season
Post by: Sterks on March 06, 2017, 05:09:25 PM
This image pertains to the melting season thread. Day 64 2017 snow cover anomaly.
Regardless of the massive snowing this winter, there is an early beginning of spring in many locations of the northern hemisphere as last year. Less snow means more insolation in areas where it already does matters. It's still early but everything counts. An equivalent of FDD might be devised for land.
Title: Re: The 2017 melting season
Post by: wili on March 06, 2017, 10:28:54 PM
Sorry if this has already been posted or if it's in the wrong thread here:

https://www.theguardian.com/world/2017/mar/06/arctic-sea-ice-disappear-world-achieves-climate-target (https://www.theguardian.com/world/2017/mar/06/arctic-sea-ice-disappear-world-achieves-climate-target)

Arctic sea ice could disappear even if world achieves climate target:

Goal of limiting rise in average global temperatures to below 2C may not prevent ice-free Arctic, scientists warn


Arctic sea ice could vanish in summers this century even if governments achieve a core target for limiting global warming set by almost 200 countries, scientists have said.

The ice has been shrinking steadily in recent decades, damaging the livelihoods of indigenous people and wildlife, such as polar bears, while opening the region to more shipping and oil and gas exploration.

Under the 2015 Paris agreement, governments set a goal of limiting the rise in average world temperatures to well below 2C (35.6F) above pre-industrial times, with an aspiration of just 1.5C.

“The 2C target may be insufficient to prevent an ice-free Arctic,” James Screen and Daniel Williamson of Exeter University wrote in the Nature Climate Change journal after a review of ice projections.

A 2C rise would still mean a 39% risk that ice would disappear in the Arctic Ocean in summers, they said.

Ice was virtually certain to survive, however, with just 1.5C of warming.

Pretty impossible to stay within 1.5 C, now, right. And really not realistic that we could stay with in 2 C anymore for that matter. So...that's that.
Title: Re: The 2017 melting season
Post by: wehappyfew on March 06, 2017, 10:57:48 PM
Here's a chart I made. I like it when R^2 is above .90... don't like the implications for ice melting.

It's the annual average of temperatures north of the Arctic circle, compared to the annual average sea ice. Temps from NCEP reanalysis, ice area from NSIDC. Both temps and ice area are shown as their anomalies from the 1979 to 2016 average.

2017 has only two months data, it is the last point to the far lower right, slightly above the trend line.

To get ice free summers... considering that summers have been declining faster than winter... I'm going to guess about 3-4 more degreesC of Arctic warming will give us ice free Aug, Sept and Oct.

With Arctic amplification running about 6 times the global average (using the same NCEP reanalysis data), we need only about 0.5 to 0.7C more globally averaged warming to get us there. Maybe 20 years at the current accelerating rate.

The first ice free minimum would happen much earlier... and that's important as a warning signal... but I see albedo feedback as the real killer here. The regular appearance of blue Arctic Ocean in August when the sun is still shining 24 hours per day... that's going to be awful to see.

(http://peakoilbarrel.com/wp-content/uploads/2017/03/597673-1.gif)
Title: Re: The 2017 melting season
Post by: Jim Williams on March 06, 2017, 11:10:25 PM
Sorry if this has already been posted or if it's in the wrong thread here:

https://www.theguardian.com/world/2017/mar/06/arctic-sea-ice-disappear-world-achieves-climate-target (https://www.theguardian.com/world/2017/mar/06/arctic-sea-ice-disappear-world-achieves-climate-target)

Arctic sea ice could disappear even if world achieves climate target:

Goal of limiting rise in average global temperatures to below 2C may not prevent ice-free Arctic, scientists warn


Arctic sea ice could vanish in summers this century even if governments achieve a core target for limiting global warming set by almost 200 countries, scientists have said.

The ice has been shrinking steadily in recent decades, damaging the livelihoods of indigenous people and wildlife, such as polar bears, while opening the region to more shipping and oil and gas exploration.

Under the 2015 Paris agreement, governments set a goal of limiting the rise in average world temperatures to well below 2C (35.6F) above pre-industrial times, with an aspiration of just 1.5C.

“The 2C target may be insufficient to prevent an ice-free Arctic,” James Screen and Daniel Williamson of Exeter University wrote in the Nature Climate Change journal after a review of ice projections.

A 2C rise would still mean a 39% risk that ice would disappear in the Arctic Ocean in summers, they said.

Ice was virtually certain to survive, however, with just 1.5C of warming.

Pretty impossible to stay within 1.5 C, now, right. And really not realistic that we could stay with in 2 C anymore for that matter. So...that's that.
I am of the "the models are all bogus" mindset.  Give me something that explains what is happening now in term of the Industrial Revolution 200 years ago and I might find some value in the argument.  Until then, let's just stick with what is actually happening.
Title: Re: The 2017 melting season
Post by: wili on March 07, 2017, 04:22:40 AM
Well, if we are going to make any claims that GW is going to be a major hazard to human and other life, we need to either model it or point to paleo-records.

Meanwhile, robertscribbler is chiming in on what is happening (or about to) in the Chukchi:

https://robertscribbler.com/2017/03/06/warm-winds-take-aim-at-chukchi-as-arctic-sea-ice-volume-hits-record-lows-during-february-of-2017/

Warm Winds Take Aim at Chukchi as Arctic Sea Ice Volume Hits Record Lows
Title: Re: The 2017 melting season
Post by: jdallen on March 07, 2017, 04:35:04 AM
Well, if we are going to make any claims that GW is going to be a major hazard to human and other life, we need to either model it or point to paleo-records.

Meanwhile, robertscribbler is chiming in on what is happening (or about to) in the Chukchi:

[url]https://robertscribbler.com/2017/03/06/warm-winds-take-aim-at-chukchi-as-arctic-sea-ice-volume-hits-record-lows-during-february-of-2017/[/url] ([url]https://robertscribbler.com/2017/03/06/warm-winds-take-aim-at-chukchi-as-arctic-sea-ice-volume-hits-record-lows-during-february-of-2017/[/url])

Warm Winds Take Aim at Chukchi as Arctic Sea Ice Volume Hits Record Lows

Time to officially shift my focus from "Refreeze" to "Melt" I think.

Scribbler's got good support from the GFS.  I've been watching the ensemble here, tracking 2M anomalies.

http://www.tropicaltidbits.com/analysis/models/?model=gfs&region=nhem&pkg=T2ma&runtime=2017030618&fh=6&xpos=0&ypos=788 (http://www.tropicaltidbits.com/analysis/models/?model=gfs&region=nhem&pkg=T2ma&runtime=2017030618&fh=6&xpos=0&ypos=788)

While we can only be reasonably assured of stuff no more than 4-5 days out, what the implication of the later stages of the model suggest is a very high level of instablility in circulation, with major potential intrusions of heat from lower latitudes.

It appears the CAA and nearby CAB will remain colder, but even short term, it looks like these areas - Okhotsk, Barents, Western Kara, Bering, Chukchi and Hudson's Bay - are going to get hammered seriously by heat.  If the long term trend holds, it will continue.
Title: Re: The 2017 melting season
Post by: Tigertown on March 07, 2017, 06:09:28 AM
Focusing on two areas. The Bering Strait and Sea, and the FJL and Svalbard Region.
March 5th vs. 6th
(http://)
Title: Re: The 2017 melting season
Post by: nicibiene on March 07, 2017, 08:08:50 AM
Sorry for being off topic  (a little) but do you already know this website of Ole Humlum? http://www.climate4you.com (http://www.climate4you.com) - maybe there is a thread for such links too?

It is full of VERY impressive graphics (includes all of shown here, compressed in impressive annual comparsion modes) and actual datas. A real treasure I will dive in today... 😊
Title: Re: The 2017 melting season
Post by: folke_kelm on March 07, 2017, 08:32:28 AM
Nicibiene,

You have to be very carefull with Ole Humlum. He is a rather scary denier, publishing papers where he is calculating out the trend and blaming all remaining changes to climate to just...natural variations, claiming in public that he did show that climate change is fully natural. Some of his papers are totally bullshit, but here in Scandinavia he is the deniers hero, like Roy Spencer in US.

regards
Folke
Title: Re: The 2017 melting season
Post by: Pmt111500 on March 07, 2017, 09:46:23 AM
I haven't acquainted myself to Ole Humlum' stuff. Presuming he's one of the great number of people who like to think most of everything humans do is 'natural' so he'd be discounting quite a bit of human influence. "I just happened to find this petrol station and my credit card fits in the slot and I get this stuff that burns so brightly i'm blinded by it"-type of denier, possibly. Has someone classified deniers into sub-types? Could be an interesting (thpugh completely futile) intellectual exercise?
Title: Re: The 2017 melting season
Post by: gerontocrat on March 07, 2017, 11:02:42 AM
Just thought all need to know that the Trumpocracy's first budget proposes a 26 percent cut in the NOAA budget (effective Oct 1).

War on climate science officially declared ?
Title: Re: The 2017 melting season
Post by: oren on March 07, 2017, 12:53:43 PM
Sorry for being off topic  (a little) but do you already know this website of Ole Humlum? [url]http://www.climate4you.com[/url] ([url]http://www.climate4you.com[/url]) - maybe there is a thread for such links too?

It is full of VERY impressive graphics (includes all of shown here, compressed in impressive annual comparsion modes) and actual datas. A real treasure I will dive in today... 😊

A quick look at the site shows it's definitely denier stuff. All charts somehow twisted.
Title: Re: The 2017 melting season
Post by: Oyvind Johnsen on March 07, 2017, 12:57:32 PM
Re Ole Humlum`s site: As a site, it is designed and written to support his denialist agenda. However, some of the graphs on the site are interesting enough, and he links to the actual, scientific sources. His comparisons of temperature data in the satellite period are worth a look. His labelling of satellite data as "quality class A", Hadcrut as "class B", and NOAA/GISS as "class C" is of course just ridiculous, but the graphs show the real data, anyway.
So deniers, of the sort who will suspect any graph presented to them by a "warmist", may discover that Earth is actually warming. (Perhaps a bit optimistic...) :)
Title: Re: The 2017 melting season
Post by: gerontocrat on March 07, 2017, 01:52:57 PM
Well, if we are going to make any claims that GW is going to be a major hazard to human and other life, we need to either model it or point to paleo-records.

Meanwhile, robertscribbler is chiming in on what is happening (or about to) in the Chukchi:

https://robertscribbler.com/2017/03/06/warm-winds-take-aim-at-chukchi-as-arctic-sea-ice-volume-hits-record-lows-during-february-of-2017/

Warm Winds Take Aim at Chukchi as Arctic Sea Ice Volume Hits Record Lows

No need to model or look at paleohistory for effect of GW on animals. GOTO sciencerecorder.com/news/2017/02/14/effectofclimatechangeonanimals. Or for a single example google "puffins in trouble".

It is not anymore so much about what will happen but what is happening.
Title: Re: The 2017 melting season
Post by: Tigertown on March 07, 2017, 02:03:49 PM
The last six or seven comments don't belong in this thread. If there is no other place for a subject, try  the Open thread. PLEASE!

http://forum.arctic-sea-ice.net/index.php/topic,1884.250.html#lastPost
Title: Re: The 2017 melting season
Post by: Shared Humanity on March 08, 2017, 12:28:37 AM
The last six or seven comments don't belong in this thread. If there is no other place for a subject, try  the Open thread. PLEASE!

[url]http://forum.arctic-sea-ice.net/index.php/topic,1884.250.html#lastPost[/url]


Seconded. This thread is to discuss the 2017 melt season which, given the current state of the ice, will be a barn burner. Let's stay on topic.
Title: Re: The 2017 melting season
Post by: ipexnet on March 08, 2017, 02:51:25 AM
The only significant (new) cracks I can see (beyond what has been seen in prior years, and beyond the laptev sea disintegration), is in the east siberian. The winds haven't been favorable for excessive cracks in the this area either, so looks to be just a factor of thin ice. Again, I really only go by the MODIS visual records as a picture is worth a thousand words. Generally the main pack looks in much better shape and must be liking the recent cold weather. Its the fringes that look terrible.  Still in awe at the data and scientific centric view of many contributors. The data (very weak) doesn't quite align with the visuals (even weaker) in my mind. So curious to see what the next few weeks provides. Any hint of winds from the beaufort or east siberian coupled with even normal heat might drastically change the picture 
Title: Re: The 2017 melting season
Post by: Tigertown on March 08, 2017, 06:10:10 AM
March 5th 6th 7th from left to right. By warm water or whatever means, there is melting in the Bering.
Title: Re: The 2017 melting season
Post by: pauldry600 on March 08, 2017, 10:49:24 AM
And March 8th to 11th are only going to exacerbate the situation further going by climate reanalyzer forecast.
Title: Re: The 2017 melting season
Post by: rboyd on March 08, 2017, 10:38:44 PM
March 11th looks really bad for the ice.
Title: Re: The 2017 melting season
Post by: DrTskoul on March 08, 2017, 11:20:44 PM
Yikes.  The cold has taken a vacation down south...
Title: Re: The 2017 melting season
Post by: jdallen on March 08, 2017, 11:48:11 PM
March 11th looks really bad for the ice.
That's bloody astonishing and fairly high confidence as it is less than three days out.
Title: Re: The 2017 melting season
Post by: Tigertown on March 09, 2017, 08:40:04 AM
 A look at one concentration forecast. I tend not to believe this play by play, but just to the effect that we can start to expect the condition of the ice to start going down overall.
CLICK IMAGE PLEASE          March 9th-18th
(http://)
Title: Re: The 2017 melting season
Post by: Adam Ash on March 09, 2017, 10:10:42 AM
When you look at those concentration maps you get the impression that there is a lot of pretty solid ice in there. 

A remarkable comment by a traveller on an icebreaker in 2009 (way back then, even) found that while the normal ice condition maps indicated lots of multi-year ice, in fact the ice breaker which would normally cruise at 13.5 knots in open water, was able to sustain 13.0 knots through that multi-year ice which turned out to be very broken ice offering virtually no resistance to sailing.  I doubt if things have improved since then.

Seven surprising results from the reduction of Arctic Sea ice cover | David Barber | TEDxUManitoba
https://www.youtube.com/watch?v=ofaoiHYKtlc (https://www.youtube.com/watch?v=ofaoiHYKtlc)

About 7:40 into the video.

So while the satellites may say its solid-ish, it is in fact pretty mushy and hence very prone to physical and thermal damage.  This confirms our impressions of the overall pack over the last season.
Title: Re: The 2017 melting season
Post by: Thomas Barlow on March 09, 2017, 11:40:34 AM
Russian researcher, Irina Orlova's, FB post, setting up camp in at the N. Pole for 2017.
Click 'not now", if it asks you to sign up for FB, and click "See Translation" to get the general idea:
https://www.facebook.com/permalink.php?story_fbid=1237228086346338&id=100001774757853 (https://www.facebook.com/permalink.php?story_fbid=1237228086346338&id=100001774757853)
Title: Re: The 2017 melting season
Post by: Tigertown on March 09, 2017, 04:39:17 PM
Adam Ash
So while the satellites may say its solid-ish, it is in fact pretty mushy and hence very prone to physical and thermal damage.  This confirms our impressions of the overall pack over the last season.
No doubt, close ups would show that. These are the best we can do for now.
(http://)
Title: Re: The 2017 melting season
Post by: Neven on March 09, 2017, 05:11:18 PM
Note to everyone: Small experiment. From now on I'm going to delete off-topic, derailing comments/rants in the most important threads. So, don't bother answering some comment that gets you agitated, because that will be deleted too. Probably not right away, but soon enough.

I want a focussed thread once the melting season starts in earnest.
Title: Re: The 2017 melting season
Post by: jai mitchell on March 09, 2017, 06:36:17 PM
Note to everyone: Small experiment. From now on I'm going to delete off-topic, derailing comments/rants in the most important threads. So, don't bother answering some comment that gets you agitated, because that will be deleted too. Probably not right away, but soon enough.

I want a focussed thread once the melting season starts in earnest.

today?
Title: Re: The 2017 melting season
Post by: romett1 on March 09, 2017, 07:25:59 PM
Recent winds have made ice edge quite fragile east of Svalbard and west of FJL.
Saturday morning 03:00 UTC is interesting - wind 28 m/s and exactly where ice is most fragile.
Images from earth.nullschool.net and https://weather.gc.ca/data/satellite/hrpt_dfo_ir_100.jpg
Title: Re: The 2017 melting season
Post by: DrTskoul on March 09, 2017, 07:35:26 PM
Note to everyone: Small experiment. From now on I'm going to delete off-topic, derailing comments/rants in the most important threads. So, don't bother answering some comment that gets you agitated, because that will be deleted too. Probably not right away, but soon enough.

I want a focussed thread once the melting season starts in earnest.

today?

Cute....
Title: Re: The 2017 melting season
Post by: RoxTheGeologist on March 09, 2017, 07:40:53 PM
Both the pacific and the Atlantic look anomalously warm over the next week. That being said, both the Gulf of St Lawrence and the Eastern Bering Sea look to be rather cold. It doesn't matter for extent if the Arctic is +20 Centigrade above average, it is still below freezing. I'll state the obvious: if the areas where ice can form are cold extent will increase despite the anomalously warm temperatures. It's why SIE is a dangerous metric to point to for sea ice loss. 
Title: Re: The 2017 melting season
Post by: gerontocrat on March 09, 2017, 08:00:24 PM
Dear Rox the Geologist,
You write that SIE is a dangerous metric to point to for sea ice loss.
In the short term I agree. For those who are dedicated to the subject I also agree.

But as a measure for showing visually to the general public where we are it is one of the best we have, even though it hides the much higher loss of volume.
And it is sea ice extent that determines insolation.

Horses for courses ?
Title: Re: The 2017 melting season
Post by: romett1 on March 09, 2017, 08:08:21 PM
Note to everyone: Small experiment. From now on I'm going to delete off-topic, derailing comments/rants in the most important threads. So, don't bother answering some comment that gets you agitated, because that will be deleted too. Probably not right away, but soon enough.

I want a focussed thread once the melting season starts in earnest.

Strongly agree!
Title: Re: The 2017 melting season
Post by: romett1 on March 09, 2017, 08:45:28 PM
Here is the latest HYCOM ice thickness forecast Mar 9 - Mar 16. Still losing precious green and yellow (3 - 4 m thick ice) to Fram Strait. Also northern part of Hudson Bay is interesting because of strong winds.
Images https://www7320.nrlssc.navy.mil/hycomARC/arctic.html
Title: Re: The 2017 melting season
Post by: RoxTheGeologist on March 09, 2017, 09:19:56 PM
Dear Rox the Geologist,
You write that SIE is a dangerous metric to point to for sea ice loss.
In the short term I agree. For those who are dedicated to the subject I also agree.

But as a measure for showing visually to the general public where we are it is one of the best we have, even though it hides the much higher loss of volume.
And it is sea ice extent that determines insolation.

Horses for courses ?

Yes, I agree, however it's also very easy for deniers to use SIE to obfuscate the true measure of losses as increases in extent happen, even if its just a thin skin of ice.
Title: Re: The 2017 melting season
Post by: jdallen on March 09, 2017, 09:54:09 PM
Also northern part of Hudson Bay is interesting because of strong winds.

The ice on the Bay has been pretty thin all season.  Most striking to me though is the Foxe Basin, which typically gets quite thick, and previously would retain ice year over year.  It seems to me it may melt out early this year.
Title: Re: The 2017 melting season
Post by: Jim Hunt on March 09, 2017, 10:00:50 PM
Russian researcher, Irina Orlova's, FB post, setting up camp in at the N. Pole for 2017.


Thanks Thomas. See the traditional dedicated thread:

"Barneo 2017 (http://forum.arctic-sea-ice.net/index.php/topic,1905)"
Title: Re: The 2017 melting season
Post by: jdallen on March 09, 2017, 10:00:55 PM
Here is the latest HYCOM ice thickness forecast Mar 9 - Mar 16. Still losing precious green and yellow (3 - 4 m thick ice) to Fram Strait. Also northern part of Hudson Bay is interesting because of strong winds.
For contrast, I think it is worthwhile to remind everyone what HYCOM thought the ice looked like last year at this time:

https://www7320.nrlssc.navy.mil/hycomARC/navo/arcticictn/nowcast/ictn2016030718_2016030800_041_arcticictn.001.gif
Title: Re: The 2017 melting season
Post by: DrTskoul on March 09, 2017, 10:16:17 PM
Here is the latest HYCOM ice thickness forecast Mar 9 - Mar 16. Still losing precious green and yellow (3 - 4 m thick ice) to Fram Strait. Also northern part of Hudson Bay is interesting because of strong winds.
For contrast, I think it is worthwhile to remind everyone what HYCOM thought the ice looked like last year at this time:

https://www7320.nrlssc.navy.mil/hycomARC/navo/arcticictn/nowcast/ictn2016030718_2016030800_041_arcticictn.001.gif

With the caveat that year over year color comparison with Hycom are to be taken with a grain of salt, YIKEs!
Title: Re: The 2017 melting season
Post by: jdallen on March 09, 2017, 10:18:45 PM
With the caveat that year over year color comparison with Hycom are to be taken with a grain of salt, YIKEs!
Try this on for size.
Title: Re: The 2017 melting season
Post by: oren on March 09, 2017, 11:03:49 PM
It doesn't matter for extent if the Arctic is +20 Centigrade above average, it is still below freezing. I'll state the obvious: if the areas where ice can form are cold extent will increase despite the anomalously warm temperatures. It's why SIE is a dangerous metric to point to for sea ice loss.
Obvious but still worth repeating, especially if dispersing winds support the cold temps.
And as we are discussing the Arctic becoming seasonally ice-free, max winter extent remains almost the same while min summer extent drops sharply. So in summer SIE is a good measure. In winter probably the best measure is PIOMAS volume.
Title: Re: The 2017 melting season
Post by: jai mitchell on March 10, 2017, 05:16:14 PM
Note to everyone: Small experiment. From now on I'm going to delete off-topic, derailing comments/rants in the most important threads. So, don't bother answering some comment that gets you agitated, because that will be deleted too. Probably not right away, but soon enough.

I want a focussed thread once the melting season starts in earnest.

today?

Cute....

ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/north/daily/data/N_seaice_extent_daily_v2.1.csv

2017,    03,  05,     14.447
Title: Re: The 2017 melting season
Post by: Tigertown on March 10, 2017, 05:56:01 PM
That does appear to be the max. and it does seem that melt momentum is building. Welcome to the 2017 melting season. Have your ticket stubs ready.
March 11th
(http://)
Title: Re: The 2017 melting season
Post by: jai mitchell on March 10, 2017, 06:59:37 PM
Love Song for the Holocene
https://www.youtube.com/watch?v=OomaNxkY-KY (https://www.youtube.com/watch?v=OomaNxkY-KY)
Title: Re: The 2017 melting season
Post by: pccp82 on March 10, 2017, 07:07:43 PM
i have only been looking at this stuff for about 5 years now.....but the early heat in Siberia is impressive and is something I will be keeping an eye on.
Title: Re: The 2017 melting season
Post by: Lord M Vader on March 10, 2017, 08:21:09 PM
If the current forecast runs from ECMWF and GFS holds, the Arctic will have a tough go for the next 10 days. And a significant ice export through Fram seems likely.

I'm however, NOT inclined to agree that the maximum has been reached! This for the reason that northerly winds likely will dominate for the next 10 days. OTOH, warmer than normal conditions will be in place over the fringe zones which likely will reduce the ice extent.
Title: Re: The 2017 melting season
Post by: Rick Aster on March 10, 2017, 10:16:30 PM
There is a broad area of fragile-looking ice in the south of the Sea of Okhotsk. Maybe that was the maximum extent. It's hard to guess.
Title: Re: The 2017 melting season
Post by: Quantum on March 10, 2017, 11:41:09 PM
Plotted arctic wide temperature anomalies over the next 7 days from Climate Reanalyser as according to the GFS.

Incredibly warm conditions followed by a rather rapid decrease in average temperature, but still much above average.
Title: Re: The 2017 melting season
Post by: Tigertown on March 11, 2017, 03:08:53 AM
I stretched this out some, so that you can see the Bering Strait and Wrangel Island, for points of reference. March 7-10    Click Image Please
(http://)
Title: Re: The 2017 melting season
Post by: Tigertown on March 11, 2017, 03:22:03 AM
Still frame of ice around FJL. Night mode.
(http://)
Title: Re: The 2017 melting season
Post by: cesium62 on March 11, 2017, 05:18:19 AM
The last six or seven comments don't belong in this thread. If there is no other place for a subject, try  the Open thread. PLEASE!

[url]http://forum.arctic-sea-ice.net/index.php/topic,1884.250.html#lastPost[/url]


Seconded. This thread is to discuss the 2017 melt season which, given the current state of the ice, will be a barn burner. Let's stay on topic.


We can't talk about the effects of the melting season on Puffins in the melting season thread?
Title: Re: The 2017 melting season
Post by: Tigertown on March 11, 2017, 05:46:57 AM
The last six or seven comments don't belong in this thread. If there is no other place for a subject, try  the Open thread. PLEASE!

[url]http://forum.arctic-sea-ice.net/index.php/topic,1884.250.html#lastPost[/url]


Seconded. This thread is to discuss the 2017 melt season which, given the current state of the ice, will be a barn burner. Let's stay on topic.


We can't talk about the effects of the melting season on Puffins in the melting season thread?


Let's move this to the appropriate thread.

http://forum.arctic-sea-ice.net/index.php/topic,1907.0.html
Title: Re: The 2017 melting season
Post by: Tigertown on March 11, 2017, 07:13:07 AM
A follow up on the gif that I posted covering the 7th thru 10th. Wrangel Island was to the right side of the gif. The following is from today(3-11) and I am posting this pic with the Island more centered to illustrate how fast the ice has gone down in this area.
Go ahead and zoom in.
(http://)
Title: Re: The 2017 melting season
Post by: romett1 on March 11, 2017, 07:44:40 AM
A follow up on the gif that I posted covering the 7th thru 10th. Wrangel Island was to the right side of the gif. The following is from today(3-11) and I am posting this pic with the Island more centered to illustrate how fast the ice has gone down in this area.
Go ahead and zoom in.
(http://)

Even currently there is constant wind (12 m/s), that is pushing ice away from coast. Should calm down by the evening, but ESS (and CAB) remains quite windy for this weekend. Image from Earth.nullschool.net
Title: Re: The 2017 melting season
Post by: Jim Hunt on March 11, 2017, 12:09:35 PM
I reckon (with medium confidence!) the maximum is now behind us. So moving threads, here's the first glimpse of the Fram Strait at visible frequencies in 2017:

http://GreatWhiteCon.info/resources/arctic-sea-ice-images/winter-201617-images/#GreenlandSea (http://GreatWhiteCon.info/resources/arctic-sea-ice-images/winter-201617-images/#GreenlandSea)
Title: Re: The 2017 melting season
Post by: Gray-Wolf on March 11, 2017, 06:10:55 PM
I know that we'd see it as the destruction of ice Jim but those who look at every skip of the graph would cry you down if we see rapid break up of the ice over our side of the basin and float out into open waters?

To see Svalbard's north shore seeinmg ice now, when it has been clear all winter, might be a taste of the next couple of weeks as the FY 'glue' holding last years rubble together lets go and the pack relaxes out into open water prior to melt?
Title: Re: The 2017 melting season
Post by: Jim Hunt on March 11, 2017, 08:21:02 PM
Those who look at every skip of the graph would cry you down if we see rapid break up of the ice over our side of the basin and float out into open waters?

A good reason to keep track of both area and extent?
Title: Re: The 2017 melting season
Post by: Tigertown on March 12, 2017, 05:26:55 AM
Extent is likely to go up as there has been a lot of dispersion and export. I don't quite know exactly what is happening to the last glob of really thick ice, but it doesn't look good. 7th-11th
(http://)
Title: Re: The 2017 melting season
Post by: Tigertown on March 12, 2017, 05:38:30 AM
Another visual, but side by side. Comparing thickness from the 6th of March to the 11th. Unless this area is under attack from warm water below, I would think disperion to be the key factor.
(http://)
Title: Re: The 2017 melting season
Post by: Tigertown on March 12, 2017, 06:16:16 AM
I don't know what is going on everybody, but it doesn't look good. I knew it was going to be an exceptional season, but it wasn't supposed take off this fast. This was just updated on the University of Bremen site. I know there is a LP, but it's not that strong and could it really make the ice go down that fast? Warm wind attacked the Chukchi and ESS for a few hours on the 10th, and at just a few degrees over freezing. What's going on?
(http://)
Title: Re: The 2017 melting season
Post by: Pmt111500 on March 12, 2017, 06:20:33 AM
What's going on?

The same as in the nearby lake? That is, 1-2 mm of defrosted snow? Lucky watery reflection on the instrument on board?
Title: Re: The 2017 melting season
Post by: Tigertown on March 12, 2017, 06:32:13 AM
What's going on?

The same as in the nearby lake? That is, 1-2 mm of defrosted snow? Lucky watery reflection on the instrument on board?
So, basically, the sat. sees a layer of melted snow, which is now water on top of the ice, instead of the ice underneath, and makes it appear to us that the ice is gone?
Title: Re: The 2017 melting season
Post by: Pmt111500 on March 12, 2017, 06:46:19 AM
What's going on?

The same as in the nearby lake? That is, 1-2 mm of defrosted snow? Lucky watery reflection on the instrument on board?
So, basically, the sat. sees a layer of melted snow, which is now water on top of the ice, instead of the ice underneath, and makes it appear to us that the ice is gone?
That's my guess. It could be the angle of the sun has to be just right for this to happen, and the sat would have to pass in the right time of the day. Not sure. Fairly sure this isn't yet meltpooling, but would be the same thing that happens when frost on grass has melted just a bit.
Title: Re: The 2017 melting season
Post by: Adam Ash on March 12, 2017, 09:06:40 AM
I imagine the sats just detect the height of a reflective layer and multiply that by ten to give thickness. In the good old days that something was stacks of solid blocks of multi-year ice shoved up into huge ridges. But today that could just be rotten ice squeezed into a heap which disperses rapidly as soon as the edge restraint relaxes.  ???
Title: Re: The 2017 melting season
Post by: jdallen on March 12, 2017, 10:30:03 AM
Tutored by Neven and others... I've come to understand that variations in the Bremen sea ice concentration numbers needs to be suspicious of short-term changes.  Wait to see if it persists for several days before becoming excite.
Title: Re: The 2017 melting season
Post by: Avalonian on March 12, 2017, 11:01:15 AM
I don't see how this effect can be dispersion, since all of the bands in that area are reducing in thickness; surely, if it were lateral collapse of piled-up slush then some of the surrounding areas would show an increase in thickness away from the peak?

From what I've read on here, it's most likely that this is some artifact and will soon go away (maybe surface water film, but it's been operating over several days, and I thought this area on nullschool and other forecasts was to have been staying way below zero at the moment - am I wrong?). If not, and this is upwelling warm water, then I guess we're stuffed. I'm a little anxious  because it strikes me that this is the sort of mechanism that could explain Jim White's records of abrupt north Greenland warming in the ice core record.

At this stage, as jdallen says, we just have to wait and see if it holds up... nervously.
Title: Re: The 2017 melting season
Post by: Peter Ellis on March 12, 2017, 11:02:57 AM
Rapid changes on Bremen are probably water vapour in the air (either as clouds or just dispersed in the air column). 

The thickness measurements at NIPR are experimental and not believable except in very qualitative terms.  They fluctuate wildly from day to day. Moreover, if you watch videos of them at times when the Beaufort gyre is spinning you can often see the older ice getting mixed into the new ice - but on some days the older ice looks thicker than the new ice, and on some days thinner than the new ice!  Basically, that product is reading _something_ about the radiation characteristics and surface characteristics of the ice, but it's not clear to me exactly what.
Title: Re: The 2017 melting season
Post by: Steven on March 12, 2017, 11:09:31 AM
Another visual, but side by side. Comparing thickness from the 6th of March to the 11th. Unless this area is under attack from warm water below, I would think disperion to be the key factor.
([url]http://i.imgur.com/wZU15gB.jpg[/url])


Those JAXA sea ice thickness maps should be taken with a grain of salt.  They seem to be overly sensitive to changes in temperature, snow etc.

The sudden "thinning" event north of the Canadian Archipelago is clearly unphysical.  I don't think it's due to dispersion.  Perhaps the algorithm is affected by snowfall:  according to GFS there has been snowfall in that region yesterday:

http://i.imgur.com/Y3tIUUp.png (http://i.imgur.com/Y3tIUUp.png)


I imagine the sats just detect the height of a reflective layer and multiply that by ten to give thickness.


Some satellites (like CryoSat) measure the sea ice freeboard.  But the AMSR2/JAXA sea ice thickness product seems to be based on a completely different approach using brightness temperatures.  I cannot find much information about it,  but a quick google search gives this June 2016 presentation by Kazutaka Tateyama:

http://injapan.no/arctic2016-day2/files/2015/06/ASIW2016.06.03_Tateyama_%C3%B6z%C3%B2z%C3%B9p.pdf (http://injapan.no/arctic2016-day2/files/2015/06/ASIW2016.06.03_Tateyama_%C3%B6z%C3%B2z%C3%B9p.pdf)

which mentions as "possible error sources":  "low pressure, snow cover, melting".
Title: Re: The 2017 melting season
Post by: Tigertown on March 12, 2017, 03:55:44 PM
I am more than happy to give it some time myself, and will keep an open mind about it. I don't claim to know the answer for certain. I do remember a comment made by Hyperion back in Feb. in the Freezing thread.

Are these thickness plots still being based on 10% freeboard or what ever similar figure is historically used for old fashioned firstyear ice? Eg/ where they are graphing 2m thick is it based on satellite measurements of  ~0.2m freeboard?
 I'm concerned that the real density might be significantly lower. if its mostly snow and  rotten honeycomb with thin ice crusts interleaved, it could be as low as 0.5 kg/litre which would make 0.2m freeboard actually ~0.4m thickness. And the blowtorch like melts in the killzone fram / svalbard / bering areas certainly look to me like what you would expect from thin and rubbish quality ice. Not solid 2m thick berg.

So I will also consider that the glob above the CAA made have not consisted of very great ice from the start. Time will tell.
Title: Re: The 2017 melting season
Post by: Andreas T on March 12, 2017, 04:48:43 PM
I am more than happy to give it some time myself, and will keep an open mind about it. I don't claim to know the answer for certain. I do remember a comment made by Hyperion back in Feb. in the Freezing thread.
.....
 Time will tell.
Based on seeing the fluctuations in the JAXA thickness plot (thickening and thinning in unlikely ways) I agree with Steven who seems to have looked into this (always a good idea to check information rather than go with what some bloke on the forum says, including me of course)
I also think that Jaxa thickness plot is based on passive microwave sensors (AMSR) and works very differently from Cryosat. Previous commenters are mixing those up.
I recall reading that this does not work well in thicker ice, but it can give an indication where  there is probably thick ice due to thicker ice usually having low surface temperature.
 
Digging out information is a bit boring, especially when it often gets ignored by commenters which prefer to voice their opinions very frequently so I'm inclined to let someone else do that.
Title: Re: The 2017 melting season
Post by: Shared Humanity on March 12, 2017, 07:33:19 PM
I don't know what is going on everybody, but it doesn't look good. I knew it was going to be an exceptional season, but it wasn't supposed take off this fast. This was just updated on the University of Bremen site. I know there is a LP, but it's not that strong and could it really make the ice go down that fast? Warm wind attacked the Chukchi and ESS for a few hours on the 10th, and at just a few degrees over freezing. What's going on?
(http://)

All FYI in the ESS and Chukchi, highly fractured, very mobile and, with the ridiculous FDD anomalies this year, not the cold hard ice we have come to expect. I expect a stormy melt season with a highly mobile ice pack and a continuation in the trend towards increased dispersion at minimum.

We saw how the big block, thick MYI, fared in the Beaufort last year. Given the location of the last remnant of MYI north of the CAA, I don't think we will see any transport of MYI into the Beaufort and we should see an early melt and wide open Pacific side of the CAB at min.
Title: Re: The 2017 melting season
Post by: Gray-Wolf on March 12, 2017, 07:54:21 PM
Once melt season is properly underway I think some will be surprised at just how fast the ice disintegrates in small floes ( last years rubble)?

Open water is the issue we face. Open water over ever increasing areas for ever increasing amounts of time.

Look at the open water in 07' and how fragmented the pack remaining was. Do the same for the rest of the years and compare with how much open water we saw throughout 2016's melt season.

2016 is the new template for ice behaviour over summer with early breakup and open water throughout the basin by solastice.
Title: Re: The 2017 melting season
Post by: Shared Humanity on March 12, 2017, 09:20:29 PM
On the Atlantic side, things are even worse. Expect a wide open Atlantic side of the CAB as well although the highly mobile ice could replenish the ice that melts in this area. The only question for me is whether (how much) of the 2m to 2.5 meter ice (the elephant trunk) will survive the melt season.

If most of it melts we will have new record minimums for SIA and SIE.
Title: Re: The 2017 melting season
Post by: Tigertown on March 12, 2017, 09:35:06 PM
On the Atlantic side, things are even worse.
And How! Nightband image.
(http://)
Title: Re: The 2017 melting season
Post by: Shared Humanity on March 12, 2017, 09:56:49 PM
None of that ice is more than 1.2 meters thick and much of it is under 1 meter.
Title: Re: The 2017 melting season
Post by: Hyperion on March 12, 2017, 09:59:57 PM
hmmm...
a few rough guesstimates calculated by various means are suggesting that with this constant motion and export of surface water and ice into a long polar basin kill zone with big wind and wave conditions mixing in with Gulfstream waters, we could have lost several metres of an arctic ocean wide fresher layer by export alone over the winter. And the constant refreezing of the exposed waters is of course releasing some brine but with so much motion I'd be surprized if this does anything but raise the salinity of the lens. Halocline collapse is looking likely. :'(
Title: Re: The 2017 melting season
Post by: DrTskoul on March 12, 2017, 10:06:50 PM
None of that ice is more than 1.2 meters thick and much of it is under 1 meter.

Summer storm fodder....
Title: Re: The 2017 melting season
Post by: RoxTheGeologist on March 12, 2017, 10:35:03 PM
hmmm...
a few rough guesstimates calculated by various means are suggesting that with this constant motion and export of surface water and ice into a long polar basin kill zone with big wind and wave conditions mixing in with Gulfstream waters, we could have lost several metres of an arctic ocean wide fresher layer by export alone over the winter. And the constant refreezing of the exposed waters is of course releasing some brine but with so much motion I'd be surprized if this does anything but raise the salinity of the lens. Halocline collapse is looking likely. :'(

The evidence of Halocline collapse is Atlantic waters penetrating out beyond the shelf and over the Nansen Basin on the surface. That phenomenon was observed by A-Team last year, a band of warm water extending from Svalbard and north of FJL. I think it's fair to assume that where that happens the halocline has broken down completely.

Title: Re: The 2017 melting season
Post by: Tigertown on March 13, 2017, 05:32:37 AM
There have been no warm winds anywhere for two days. The up to about 3oC wind on the 10th was in a very isolated area, not over the whole Arctic. The average surface air temps. are between -20oC to -250C. There has been some wind, just no warmth in it. My only thoughts at this point are in regard to the water under the ice, as I do not know much about downward long wave radiation. Could it cause surface melt on the ice without heating the air? Either way, things are looking worse. I am trying to keep an open mind, but as each day goes by a fluke seems less likely.
(http://)
Title: Re: The 2017 melting season
Post by: jdallen on March 13, 2017, 05:47:04 AM
My only thoughts at this point are in regard to the water under the ice, as I do not know much about downward long wave radiation. Could it cause surface melt on the ice without heating the air?
There'd have to be an awful lot of it, and it by nature would raise air temperatures as well, so no, I don't think you'd get surface melt without increasing air temperatures.

Bottom melt is a different issue, and with temperatures above -20c, we're looking at their being enough excess heat flow through the ice that some of it would get captured as phase change.  The ice won't disappear as surface temps are still well below freezing, but the balance of heat flow means any ice much over a meter thick may have to contend with dynamics that prevent enough heat passing through the ice to prevent it from melting.

The balance would get restored as you reduce the thickness and permit greater heat flow.  At this stage any melt would be measured in a handful of CM at most.
Title: Re: The 2017 melting season
Post by: Tigertown on March 13, 2017, 06:22:49 AM
I am not big on the surface melt myself, but was considering it because a couple of people mentioned the possibility of a snow layer on top of the ice that may be melting and fooling the sat. instruments. And that's the thing; melting from what?

I think it a much stronger possibility that there is both dispersion and upwelling, and that these are breaking up the rotten ice. Some melting happening, maybe, but mostly breaking up.

P.S. Whether it be instruments or whatever, Wipneus' Volume chart based on JAXA data just took a nosedive. I am just observing this. I am not trying to dogmatically say that I understand it all. Perhaps it is some error, though it would be a confounding one.
(http://)
Title: Re: The 2017 melting season
Post by: Adam Ash on March 13, 2017, 08:40:19 AM
I cannot find ice pack snow thickness data, but I winder if the high air moisture content has led to these lower temperatures dropping snow over the pack, hence insulating it from the cold air and reducing ice thickness build?  That would allow bottom melt to continue apace, with thickness un-replenished by heat loss upwards to the air?
Title: Re: The 2017 melting season
Post by: Jim Hunt on March 13, 2017, 09:15:13 AM
According to Environment Canada (http://weather.gc.ca/analysis/index_e.html) the latest Arctic cyclone bottomed out at 971 hPa at 06:00 UTC yesterday. This morning MSLP has risen to all of 973 hPa:
Title: Re: The 2017 melting season
Post by: Hyperion on March 13, 2017, 10:43:27 AM
The overall atmospheric circulations in both hemispheres are reminiscent of tropical cyclones with dual eyewalls. there only one significant low in each hemisphere right now. And they both seem to extend in height right up to near 10hPa - 30km altitude. The stratospheric set up over the nth atlantic seems to be dropping them like eggs to invade the arctic, and the helical infeed at high levels is beyond my ability to speculate on consequences. There seems very little cyclonic activity in either hemisphere outside of the big low pressure eyes in each. Im intrigued as to whether the high altitude east to west flow moving from the south, and now flirting with the equator is going to continue migrating north with the equinox passing and its twin u-turn outflows into the Nth hemisphere vortexes strengthen and consolidate.  Dumping southern summer energy on the northern polar system.
Anyone remember kansas? If this is a mode setting in solidly we might be in for desert zones from 35 sth to 35 nth latitudes. Looks like any tropical lows trying to form are getting their tops sheared off and stillborn. The Hadley cells losing the war.
We may have an explanation for why it was cosy for temperate climate critters, at least seasonally, in northern Europe, Siberia and Alaska after the big melt pulse 13KA BP. This sort of thing could have it very warm and wet in those places.
Title: Re: The 2017 melting season
Post by: Jim Hunt on March 13, 2017, 11:27:12 AM
Anyone remember kansas?
Title: Re: The 2017 melting season
Post by: Tigertown on March 13, 2017, 11:29:08 AM
@Hyperion
The circulation patterns over the Arctic match all the way up to 250 hpa, but change between there and 70 hpa.(If I am looking at it, wrong please correct me) If you have the mslp button on, while on Earth NS it makes it appear to match higher and will read wrong sometimes even after you turn it off. Still I find it pretty remarkable that the patterns match all the way up to jet stream height. Not saying that has never happened at all, but I don't recall seeing it. Anyone have a clue as to what this might mean?
Title: Re: The 2017 melting season
Post by: Neven on March 13, 2017, 11:50:54 AM
My only thoughts at this point are in regard to the water under the ice, as I do not know much about downward long wave radiation. Could it cause surface melt on the ice without heating the air?

There'd have to be an awful lot of it, and it by nature would raise air temperatures as well, so no, I don't think you'd get surface melt without increasing air temperatures.


Melt onset is determined by downwelling longwave radiation. From Mortin et al. (http://onlinelibrary.wiley.com/doi/10.1002/2016GL069330/full) (2016):

"The timing of melt onset affects the surface energy uptake throughout the melt season. Yet the processes triggering melt and causing its large interannual variability are not well understood. Here we show that melt onset over Arctic sea ice is initiated by positive anomalies of water vapor, clouds, and air temperatures that increase the downwelling longwave radiation (LWD) to the surface. The earlier melt onset occurs; the stronger are these anomalies. Downwelling shortwave radiation (SWD) is smaller than usual at melt onset, indicating that melt is not triggered by SWD. When melt occurs early, an anomalously opaque atmosphere with positive LWD anomalies preconditions the surface for weeks preceding melt. In contrast, when melt begins late, clearer than usual conditions are evident prior to melt. Hence, atmospheric processes are imperative for melt onset. It is also found that spring LWD increased during recent decades, consistent with trends toward an earlier melt onset."

Title: Re: The 2017 melting season
Post by: Peter Ellis on March 13, 2017, 11:51:18 AM
Could it cause surface melt on the ice without heating the air? Either way, things are looking worse. I am trying to keep an open mind, but as each day goes by a fluke seems less likely.

Stop panicking.  It's clouds - water vapour in the air rather than surface meltwater or open ocean water.  From the standpoint of this satellite, it's all water. Rapid day-to-day fluctuations on the Bremen map are almost ALWAYS clouds - they try to algorithmically filter them out but it's not always possible. 

Bremen is a couple of days delayed relative to other sources.  Here are the Worldview images for the 10th March for Hudson Bay and the Arctic Ocean. Observe the thick white clouds concealing the ice (red) in the areas of apparent "low concentration" on the Bremen maps.  It's particularly convincing for Hudson Bay, where you can see the exact curved shape of the weather system.
http://go.nasa.gov/2mRMNwv (http://go.nasa.gov/2mRMNwv)
http://go.nasa.gov/2mirBfR (http://go.nasa.gov/2mirBfR)

Title: Re: The 2017 melting season
Post by: Peter Ellis on March 13, 2017, 11:52:44 AM
I cannot find ice pack snow thickness data, but I winder if the high air moisture content has led to these lower temperatures dropping snow over the pack, hence insulating it from the cold air and reducing ice thickness build? 
So nearly correct.  High air moisture correct is directly (and erroneously) detected as lowered ice concentration.  It'll bounce back up again when the clouds pass.
Title: Re: The 2017 melting season
Post by: Neven on March 13, 2017, 11:56:55 AM
I've been looking at ASCAT radar images and saw some interesting features. Here's an animation for the past week, and those features are in the first frame (white circle and rectangle):

(https://lh3.googleusercontent.com/XMBmRiwJMCpB7EdRTRfPQwG9xSNo6OqK-00iJTjc7XgZHgHq9_Q50KjQK7WY3bGtD9N2JRt89DTx9uj4bDfK_Ytaegp2Yje738UfK00tSsAyqK5AuZwDvNYyIhzkjLrIPUx_2ywWEAVexMdL1vcf3PPjBwZHHIlRDMbLXxe3AGzKmawM0yC9Yw4RMjVoWGMF4jcxCylZNcf3wJLmtV4RZvlUul4awGj39CL4jGPxlnSclZMusv34I0ZEhFh9Dpk6CdK2D3oepWnM1pKso1sN_wUV2se2TWqBLwgZQhea32YQMBgzZD91s9ZJlI9DE1k4cbTLLaDjfBBAFxZfPtSRIsMLtNtHZ7MPq4DIa6dOQsT_xIR2CYb0pWySCeAWq6l9LZC8yPHqWH-1fAz3lpihtSknBRt3aexrvXiNr19T8_qez_esQvolYkW0gwaZ1aKiCmXjdgy3W_QWmVWGXbagfWiwX_Mu0al-aW79N7FnPsVEcv00K6EPHk_NMP7lbmf-TNT5vlofp7unuULlTqD95pCd2JU8ndxPcr1w3JUht0hjpySn7N7KBL-QqdWdi7XpA9Ij908xOZUfxrHdUFnU5gnLLp7oGdIx3hDe_9WqCFEJRahCT5di=w496-h468-no)

Usually, dark means thin in radar images, and these features have been there since November. The one in the circle looks especially interesting, but I don't know if it means these regions are  thinner. And I haven't compared to other years yet either, but I thought I'd throw it out here to see what you guys think.
Title: Re: The 2017 melting season
Post by: Peter Ellis on March 13, 2017, 12:02:46 PM
Extent is likely to go up as there has been a lot of dispersion and export. I don't quite know exactly what is happening to the last glob of really thick ice, but it doesn't look good. 7th-11th

Look at your own animation.  And I mean really look, don't just see what you want to see.  The "arm" of ice sticking out into the East Siberian Sea is easily visible. We know this is older ice that survived from last year.  It must therefore be thicker than the immediately neighbouring first year ice, since as the new ice forms, the already-existing ice gets thicker.  One class of ice can't overtake the other in thickness.

BUT

In most of the frames, the old ice arm is a darker green, i.e. apparently "thinner" than this ice around it.  That alone is enough to tell you that this product is WRONG and is not correctly measuring ice thickness.  It's not even consistent from day to day: in some frames the old ice arm does indeed look thicker than its surroundings.

Stop trying to read more into these pictures than they will support.  They're a good way of getting a general overview of the boundaries between older and younger ice. No more.  They are not numerically accurate, and do not genuinely measure ice thickness and volume.
Title: Re: The 2017 melting season
Post by: Tigertown on March 13, 2017, 12:18:18 PM
@Peter Ellis
Don't mistake my enthusiasm for panicking. I am trying to observe what is happening. That is all.
I am looking at every available asset to evaluate the situation. I have stated several times that I don't have any preconceptions about it all. You are right about the moisture playing a role, but I think more along the line of Neven's quote from Mortin et al. Plus, I am not looking at a one or two day fluke, as more than one person has said. What I see has been going on a few days, and therefore deserves at least to be monitored. If it turns out one way or the other, that's that.

BTW
Hudson Bay ice is in bad shape. I have been looking at it all winter and it never really thickened like it should have. The clouds and storms and turbulence are hurting it, just as the sat. is showing.
Title: Re: The 2017 melting season
Post by: Shared Humanity on March 13, 2017, 02:11:31 PM
I've been looking at ASCAT radar images and saw some interesting features. Here's an animation for the past week, and those features are in the first frame (white circle and rectangle):

Usually, dark means thin in radar images, and these features have been there since November. The one in the circle looks especially interesting, but I don't know if it means these regions are  thinner. And I haven't compared to other years yet either, but I thought I'd throw it out here to see what you guys think.

Whatever those two dark areas are, it is ice and not clouds. I'm inclined to think it is thin ice. The thin ice in the rectangle is interesting in that it appears to mimic the Laptev bite we often see at the end of a melt season. I am wondering if there is an ocean phenomena (upwelling of warm water) that is a persistent feature in this area of the ocean. When the ice was very thick, this feature was fully obscured during the winters and only became visible during aggressive melt seasons. Now, with wildly warm winters (FDD anomaly) this upwelling prevents the ice from thickening.

This is, of course, wild speculation on my part.
Title: Re: The 2017 melting season
Post by: Shared Humanity on March 13, 2017, 02:19:10 PM
As A-Team is missing, I try to operate with gif's. Latest Hycom forecast Mar 8 - Mar 12. Notice Fram export, Bering Strait and Chukchi Sea. Images from: https://www7320.nrlssc.navy.mil/hycomARC/arctic.html

If you look at this animation, there is a similar feature although it is not aligned exactly.
Title: Re: The 2017 melting season
Post by: johnm33 on March 13, 2017, 03:47:03 PM
Hyperion I don't often check the 2[1]  links below but have been for a couple of weeks or so, just to follow the highs/lows in the arctic, the weather systems have been flowing from the tropics to the arctic all that time, at least on the atlantic side.
http://synoptic.envsci.rutgers.edu/site/sat/sat.php?sat=nhem&url=../imgs/wv_nhem_anim.gif (http://synoptic.envsci.rutgers.edu/site/sat/sat.php?sat=nhem&url=../imgs/wv_nhem_anim.gif)
http://synoptic.envsci.rutgers.edu/site/sat/sat.php?sat=nhem&url=../imgs/ir_nhem_anim.gif (http://synoptic.envsci.rutgers.edu/site/sat/sat.php?sat=nhem&url=../imgs/ir_nhem_anim.gif)
I'm thinking the circle in Nevens animation closely coincides with the Laptev end of the Amundsen/Nansen basins, and that Atlantic currents are forced all the way across the north barents sea shelf, some fraction escapes to the NSI side of Lomonosov but the rest circulates venting heat/vapour into the area. The way that settles out depends on current weather, but snow or mist it conditions the ice.. The rectangle seems associated with the Alpha/Mendeleyev ridge and Makarov basin, so I suspect it's ice passing over the ridges, including Lomonosov, stirring the depths of Makarov.
It's worth clicking through from the 8th to see the added impetus the tides gives to the heat ingress
http://go.nasa.gov/2miRfkr (http://go.nasa.gov/2miRfkr)
Title: Re: The 2017 melting season
Post by: seaicesailor on March 13, 2017, 03:53:52 PM
I've been looking at ASCAT radar images and saw some interesting features. Here's an animation for the past week, and those features are in the first frame (white circle and rectangle):

(https://lh3.googleusercontent.com/XMBmRiwJMCpB7EdRTRfPQwG9xSNo6OqK-00iJTjc7XgZHgHq9_Q50KjQK7WY3bGtD9N2JRt89DTx9uj4bDfK_Ytaegp2Yje738UfK00tSsAyqK5AuZwDvNYyIhzkjLrIPUx_2ywWEAVexMdL1vcf3PPjBwZHHIlRDMbLXxe3AGzKmawM0yC9Yw4RMjVoWGMF4jcxCylZNcf3wJLmtV4RZvlUul4awGj39CL4jGPxlnSclZMusv34I0ZEhFh9Dpk6CdK2D3oepWnM1pKso1sN_wUV2se2TWqBLwgZQhea32YQMBgzZD91s9ZJlI9DE1k4cbTLLaDjfBBAFxZfPtSRIsMLtNtHZ7MPq4DIa6dOQsT_xIR2CYb0pWySCeAWq6l9LZC8yPHqWH-1fAz3lpihtSknBRt3aexrvXiNr19T8_qez_esQvolYkW0gwaZ1aKiCmXjdgy3W_QWmVWGXbagfWiwX_Mu0al-aW79N7FnPsVEcv00K6EPHk_NMP7lbmf-TNT5vlofp7unuULlTqD95pCd2JU8ndxPcr1w3JUht0hjpySn7N7KBL-QqdWdi7XpA9Ij908xOZUfxrHdUFnU5gnLLp7oGdIx3hDe_9WqCFEJRahCT5di=w496-h468-no)

Usually, dark means thin in radar images, and these features have been there since November. The one in the circle looks especially interesting, but I don't know if it means these regions are  thinner. And I haven't compared to other years yet either, but I thought I'd throw it out here to see what you guys think.
FYI and FYI according to the russian service that you point to in the ASIG, Neven. The elongated structure seems trapped FYI between the two surviving arms of ice in September, and the other region has been growing in extension as the surviving ice drifted northwards.
Title: Re: The 2017 melting season
Post by: Neven on March 13, 2017, 04:32:57 PM
Thanks, sis, that explains it.
Title: Re: The 2017 melting season
Post by: Paddy on March 13, 2017, 05:17:44 PM
Btw, Neven, "sis" is usually a colloquialism for "sister". Although I'm sure seaicesailor wouldn't be offended by the monikor.
Title: Re: The 2017 melting season
Post by: Neven on March 13, 2017, 06:24:13 PM
Thanks, bro.  ;)
Title: Re: The 2017 melting season
Post by: Hyperion on March 13, 2017, 07:04:06 PM
@Hyperion
The circulation patterns over the Arctic match all the way up to 250 hpa, but change between there and 70 hpa.(If I am looking at it, wrong please correct me) If you have the mslp button on, while on Earth NS it makes it appear to match higher and will read wrong sometimes even after you turn it off. Still I find it pretty remarkable that the patterns match all the way up to jet stream height. Not saying that has never happened at all, but I don't recall seeing it. Anyone have a clue as to what this might mean?
The circulation exists anticlockwise over the arctic one and the Antarctic clockwise still at the 70hpa about 18km. Above that the arctic one has a clockwise up to 270 kmph vortex. Possibly its high altitude outflow. Certainly the only point in the 10hpa world colder than below it. But intermeshed is a raging anticlockwise spool winding in a jet from the equator that passes 1.5 times around the planet. I'm hypothesising a mechanism  may exist for that one assisting spawning the nth Atlantic new ones that keep forming directly beneath it.
Title: Re: The 2017 melting season
Post by: Tigertown on March 13, 2017, 07:14:16 PM
@Hyperion
The circulation patterns over the Arctic match all the way up to 250 hpa, but change between there and 70 hpa.(If I am looking at it, wrong please correct me) If you have the mslp button on, while on Earth NS it makes it appear to match higher and will read wrong sometimes even after you turn it off. Still I find it pretty remarkable that the patterns match all the way up to jet stream height. Not saying that has never happened at all, but I don't recall seeing it. Anyone have a clue as to what this might mean?
The circulation exists anticlockwise over the arctic one and the Antarctic clockwise still at the 70hpa about 18km. Above that the arctic one has a clockwise up to 270 kmph vortex. Possibly its high altitude outflow. Certainly the only point in the 10hpa world colder than below it. But intermeshed is a raging anticlockwise spool winding in a jet from the equator that passes 1.5 times around the planet. I'm hypothesising a mechanism  may exist for that one assisting spawning the nth Atlantic new ones that keep forming directly beneath it.

A 3-D  model would really come in handy for that.
Title: Re: The 2017 melting season
Post by: seaicesailor on March 13, 2017, 08:39:29 PM
Btw, Neven, "sis" is usually a colloquialism for "sister". Although I'm sure seaicesailor wouldn't be offended by the monikor.
LOL
I didn't notice (not native in english tongue) so fine with me.
Title: Re: The 2017 melting season
Post by: Andreas T on March 13, 2017, 08:55:38 PM
I got an idea from a post by johnm33 earlier where he referred to the temperature band on worldview. So. I took a look at it from the start of winter til now. February was the only month that didn't see a lot of warmth sneak in under the ice. March was a different story as seen here in the gif.
....
Thank you for putting this together, but I am puzzled why you think this shows warmth sneaking in "under the ice". Can you explain?
The thermal infrared band shows clouds (warmer low clouds and colder high cloud tops) or snow / ice surface (which quickly gets cold under clear sky, when it is visible from the satellite)
Thinner ice shows up as warmer areas, especially when frozen over very recently, and open ocean is the warmest surface seen in arctic winter even if it is near freezing temperature.
Title: Re: The 2017 melting season
Post by: magnamentis on March 13, 2017, 09:05:23 PM
I got an idea from a post by johnm33 earlier where he referred to the temperature band on worldview. So. I took a look at it from the start of winter til now. February was the only month that didn't see a lot of warmth sneak in under the ice. March was a different story as seen here in the gif. CLICK IMAGE March 1st- 12th
Also, I made a Youtube  video of Dec. 1st til March 12th for the bigger picture. Probably not a huge amount of energy coming in at any one time this way, but remember it can't escape into space as easily as it used to.  https://www.youtube.com/watch?v=KmPWtIt0r3k (https://www.youtube.com/watch?v=KmPWtIt0r3k)
(http://)

could this kind of temperature analyzes be used to at least cross-check on volume claims by the different models?

as it seems the temps correlate well enough with the thickness so that one could at least see wether any claim by the models is possible or out of question. for example that would mean that if a lot of heat dissipates into the atmosphere which will show as higher temps in this image, one could discount the possibility of 5m thick ice in the same area and vice versa.

just a thought to help get to terms with the not yet solved issue with all the thickness models which perhaps at the end are all not correct, but a mix of them.

end of brain storm, may the experts consider and eventually ponder over this, i'm just saying that often mixing/combining skills information and ingredients will finally do the maths. at least the past has shown
that this is often true :-)
Title: Re: The 2017 melting season
Post by: Andreas T on March 13, 2017, 10:34:58 PM
I've been looking at ASCAT radar images and saw some interesting features. Here's an animation for the past week, and those features are in the first frame (white circle and rectangle):

([url]https://lh3.googleusercontent.com/XMBmRiwJMCpB7EdRTRfPQwG9xSNo6OqK-00iJTjc7XgZHgHq9_Q50KjQK7WY3bGtD9N2JRt89DTx9uj4bDfK_Ytaegp2Yje738UfK00tSsAyqK5AuZwDvNYyIhzkjLrIPUx_2ywWEAVexMdL1vcf3PPjBwZHHIlRDMbLXxe3AGzKmawM0yC9Yw4RMjVoWGMF4jcxCylZNcf3wJLmtV4RZvlUul4awGj39CL4jGPxlnSclZMusv34I0ZEhFh9Dpk6CdK2D3oepWnM1pKso1sN_wUV2se2TWqBLwgZQhea32YQMBgzZD91s9ZJlI9DE1k4cbTLLaDjfBBAFxZfPtSRIsMLtNtHZ7MPq4DIa6dOQsT_xIR2CYb0pWySCeAWq6l9LZC8yPHqWH-1fAz3lpihtSknBRt3aexrvXiNr19T8_qez_esQvolYkW0gwaZ1aKiCmXjdgy3W_QWmVWGXbagfWiwX_Mu0al-aW79N7FnPsVEcv00K6EPHk_NMP7lbmf-TNT5vlofp7unuULlTqD95pCd2JU8ndxPcr1w3JUht0hjpySn7N7KBL-QqdWdi7XpA9Ij908xOZUfxrHdUFnU5gnLLp7oGdIx3hDe_9WqCFEJRahCT5di=w496-h468-no[/url])

Usually, dark means thin in radar images, and these features have been there since November. The one in the circle looks especially interesting, but I don't know if it means these regions are  thinner. And I haven't compared to other years yet either, but I thought I'd throw it out here to see what you guys think.

tracking the area in the circle back to september I can confirm what SIS spotted in the russian ice chart: this was open water on Sept 17th (changing shape somewhat) the outline seems to be formed by ice movement at the time when it froze over a few days after that.
Clouds obscure the area in the visible images but AMSR brightness temp helps to track it and relate worldview to the ASCAT images.
attached are:
https://manati.star.nesdis.noaa.gov/ascat_images/ice_image/msfa-NHe-a-2016260.sir.gif (https://manati.star.nesdis.noaa.gov/ascat_images/ice_image/msfa-NHe-a-2016260.sir.gif)
and http://go.nasa.gov/2mTOnOl (http://go.nasa.gov/2mTOnOl)
Title: Re: The 2017 melting season
Post by: Andreas T on March 13, 2017, 11:34:00 PM
...
 For example, if a surface area shows up colder one day and warmer the next, did the ice get thinner there overnight? Did something heat the area from above? Or is it more likely, for the time of year that warm water moved underneath and is now showing up?
No, if the area shows up warmer from one day to the next, this is caused by warm and moist air moving in which in arctic winter forms clouds. These clouds are opaque to IR and therefore you see the clouds and not the ice surface. When you zoom in you can distinguish the cracked patterns of ice surface and the softer contours of fast moving clouds. If the clouds are very thick the cloud tops are at a much higher altitude and cold by adiabatic expansion, but low clouds will show up warmer than the ice surface. Below the clouds the ice surface will warm but not necessarily to the temperature of the cloud, it is quite likely that there is a temperature inversion. The ice surface which was visible from the satellite was cold because it is radiating into space (where the satellite sees its IR emission). When clouds move between ice and satellite they radiate (due to their temperature and emissivity) Downwelling Longwave Radiation to give the ice surface a less negative radiation balance (or a positive one if the clouds are warmer than the ice). Since the ice surface also has a heat flux from the sea below, this less negative radiation balance is enough to raise its temperature. But in winter the bulk of the ice is still colder than freezing point and there is no melting. (unless the water is sufficiently above the freezing temp, as we see off Spitsbergen)
Title: Re: The 2017 melting season
Post by: Cid_Yama on March 14, 2017, 02:42:57 AM
DMI now shows temperatures back up 5-7C above normal (250-255K). It is now too late for cold temperatures to permit a recovery in volume.

In another 10 days we start the sharp spring climb in temperatures as the sun returns.  The current and coming storms pretty much preclude any serious return of cold weather.

What we have is about what we are going to get, ice-wise.

Yes, as I said, March surprise.

Title: Re: The 2017 melting season
Post by: Tigertown on March 14, 2017, 09:42:16 AM
Winds look to really favor Fram export over the next few days. Not much quality to the ice in that area, so as to offer any resistance.
Title: Re: The 2017 melting season
Post by: romett1 on March 14, 2017, 10:06:42 AM
I will prepare good coffee over next several days. Strong winds near Svalbard support Fram export Mar 14 - Mar 19 and Mar 21 (GFS). Also low pressures over Arctic and higher than usual temperatures. Here is example of Wed ice drift estimate.
Image: https://www7320.nrlssc.navy.mil/hycomARC/arctic.html
Title: Re: The 2017 melting season
Post by: seaicesailor on March 14, 2017, 10:32:20 AM
Yep. Mean temperatures won't be telling half of the story. Kara, Barentsz, Okhotsk, Bering seas suffering anomalous temps especially that wave coming from Eurasia according to GFS (0 -168h forecasts below). The low will be pulling and pushing, with a well defined front of temperature. Those cracks along the Asian coast will eventually  refreeze but chances are we are going to see them a lot in Tealights maps come May.
The only part that is faring well is the young ice of the Beaufort sea at the moment. Quiet and cold.
Title: Re: The 2017 melting season
Post by: VeliAlbertKallio on March 14, 2017, 10:52:43 AM
Although I also think the thinness of sea ice is the reason here, I am sure other factors can also play into this such as snow darkened by some substances like ash and smoke particles that are fallen onto snow and ice surfaces - even during winter. These could alter the radiative balance (flow) of both visible light and long wave spectrum. There is also possibility of properties of silt from the rivers and residual heat from turbulent and mixing break water (altering densities temperature-salinity) that can push more or less heat through ice cover. Indeed, in summer season I have seen rebounce radiation from sea water managing to make its way through snow covered ice to surface making slight variations in the colour of sea ice/snow cover as colour of water shines through ice and snow. (The water beneath ice is illuminated in colours of blue, green, brown or gray depending on riparian discharge and algae growth - noticing these through ice and snow requires a good eye to notice the colours against the immense glare of snow in satellite images.) How significant these are in long-wave region of spectrum, I do not know. In visible light the colours of water beneath ice and snow are hard to see on many occasions.

In addition, the barren ice, thickness of snow cover, and its compactness all change heat signature from sea (besides sea ice thickness). These complications could be more pronounced in interpreting future images as there might be heavier snowfalls on ice ("lake-snow effect on sea ice off the open areas" was, after all, once proposed as the cause of immense snow falls of the Ice Ages, proposed by Maurice Ewing and William Donn. [Ewing-Donn Lake-Snow Effect of the Arctic as cause of open Arctic Ocean flipping into the Ice Age in 1950's. Their case failed in sediment cores leading to reversion back to earlier Milutin Milankovic's orbital forcing effects as driver of glaciations-deglaciations]. Methane laden sea water also has different radiative properties, but whether it is significant in water is another matter as thermal inertia of water is massive in comparison to air. If it were, then water from above methane clathrates would appear warmer.

I've been looking at ASCAT radar images and saw some interesting features. Here's an animation for the past week, and those features are in the first frame (white circle and rectangle):

([url]https://lh3.googleusercontent.com/XMBmRiwJMCpB7EdRTRfPQwG9xSNo6OqK-00iJTjc7XgZHgHq9_Q50KjQK7WY3bGtD9N2JRt89DTx9uj4bDfK_Ytaegp2Yje738UfK00tSsAyqK5AuZwDvNYyIhzkjLrIPUx_2ywWEAVexMdL1vcf3PPjBwZHHIlRDMbLXxe3AGzKmawM0yC9Yw4RMjVoWGMF4jcxCylZNcf3wJLmtV4RZvlUul4awGj39CL4jGPxlnSclZMusv34I0ZEhFh9Dpk6CdK2D3oepWnM1pKso1sN_wUV2se2TWqBLwgZQhea32YQMBgzZD91s9ZJlI9DE1k4cbTLLaDjfBBAFxZfPtSRIsMLtNtHZ7MPq4DIa6dOQsT_xIR2CYb0pWySCeAWq6l9LZC8yPHqWH-1fAz3lpihtSknBRt3aexrvXiNr19T8_qez_esQvolYkW0gwaZ1aKiCmXjdgy3W_QWmVWGXbagfWiwX_Mu0al-aW79N7FnPsVEcv00K6EPHk_NMP7lbmf-TNT5vlofp7unuULlTqD95pCd2JU8ndxPcr1w3JUht0hjpySn7N7KBL-QqdWdi7XpA9Ij908xOZUfxrHdUFnU5gnLLp7oGdIx3hDe_9WqCFEJRahCT5di=w496-h468-no[/url])

Usually, dark means thin in radar images, and these features have been there since November. The one in the circle looks especially interesting, but I don't know if it means these regions are  thinner. And I haven't compared to other years yet either, but I thought I'd throw it out here to see what you guys think.

tracking the area in the circle back to september I can confirm what SIS spotted in the russian ice chart: this was open water on Sept 17th (changing shape somewhat) the outline seems to be formed by ice movement at the time when it froze over a few days after that.
Clouds obscure the area in the visible images but AMSR brightness temp helps to track it and relate worldview to the ASCAT images.
attached are:
[url]https://manati.star.nesdis.noaa.gov/ascat_images/ice_image/msfa-NHe-a-2016260.sir.gif[/url] ([url]https://manati.star.nesdis.noaa.gov/ascat_images/ice_image/msfa-NHe-a-2016260.sir.gif[/url])
and [url]http://go.nasa.gov/2mTOnOl[/url] ([url]http://go.nasa.gov/2mTOnOl[/url])
Title: Re: The 2017 melting season
Post by: seaicesailor on March 14, 2017, 05:11:19 PM
Looking closely thru the ECMWF to the "yet another" bomb storm from the North Atlantic in four- five days, I think it is going to make puree. And it comes with friends from Norway Kara and the now native or permanent resident of the Arctic. Storms unleashed until when.
Title: Re: The 2017 melting season
Post by: jdallen on March 14, 2017, 06:08:14 PM
That "bomb" is currently giving 30CM of snow to my sister near Boston...
Title: Re: The 2017 melting season
Post by: romett1 on March 14, 2017, 07:59:22 PM
Here is the latest HYCOM ice thickness forecast Mar 14 - Mar 21. Confirms solid Fram export and also Kara Sea thinning (near Novaya Zemlya). Also Laptev Sea coast and ESS coast are not in a good position. On the other hand Beaufort Sea seems to be better so far.
Images: https://www7320.nrlssc.navy.mil/hycomARC/arctic.html
Title: Re: The 2017 melting season
Post by: seaicesailor on March 14, 2017, 08:39:00 PM
I must say my confidence in ACNFS thickness has grown this freezing season, some late tweak in 2015 or 2016 must have improved it since it is not so far as it used to wrt Cryosat and PIOMAS (granted there are differences). Similarities as well with the AMSR2-based product in the shape of the old ice, with ASCAT patterns etc. The same I DON'T feel about the DMI HYCOM.
I doubt the confidence will remain during summer.
Title: Re: The 2017 melting season
Post by: slow wing on March 14, 2017, 08:42:52 PM
Thanks Romett1. Yes, the HYCOM prediction is scary, with a lot of thicker ice either exiting through the Fram Strait or else heading in that direction.

  A lot of the thickening in the Beaufort Sea appears to be from compression, with the ice blown towards the Alaskan and Canadian Arctic coastlines.

  It's going to be critical how much new ice grows over the next month on the Siberian side to replace the ice that has migrated West. Are we going to have much of the thin ice on the Atlantic side of the Laptev Sea melted out and exposed to peak insolation by around the Summer solstice?
Title: Re: The 2017 melting season
Post by: jdallen on March 14, 2017, 10:06:15 PM
... Are we going to have much of the thin ice on the Atlantic side of the Laptev Sea melted out and exposed to peak insolation by around the Summer solstice?
It's quite plausible though far from certain.

What I noted was the rapid melt in the western Kara. That retreat could amplify changes in the Laptev and Barents.

The ice exiting the Fram does appear to be from exactly the densest remaining MYI in the basin aside from that packed along the CAA.  Hard to think of worse ice to have destroyed this early in the season.
Title: Re: The 2017 melting season
Post by: Tigertown on March 14, 2017, 10:39:55 PM
You have to wonder if the thick ice above the CAA isn't the product of numerous compaction events. It seems to break up if you look at the wrong way. It just doesn't seem dense or homogeneous like MYI should be. If that is the case, there may be even less MYI left than we thought.
Title: Re: The 2017 melting season
Post by: jdallen on March 14, 2017, 10:51:31 PM
You have to wonder if the thick ice above the CAA isn't the product of numerous compaction events. It seems to break up if you look at the wrong way. It just doesn't seem dense or homogeneous like MYI should be. If that is the case, there may be even less MYI left than we thought.
No doubt about compaction as the ice has been mobile.

I credit the warmer ice temperatures as responsible for the ice's apparent friable condition.  It loses mechanical strength  rapidly as you get above -30C or so.
Title: Re: The 2017 melting season
Post by: subgeometer on March 15, 2017, 12:00:09 AM
The GFS forecast shows rain areas in the Kara Sea every day for the next 5 days.
Title: Re: The 2017 melting season
Post by: Tigertown on March 15, 2017, 02:21:10 AM
 I thought it might be at least a little interesting to see what the export ready ice looks like at this time.            CLICK IMAGE TO ACTIVATE PLEASE
(http://)
Title: Re: The 2017 melting season
Post by: Neven on March 15, 2017, 09:30:10 AM

It's going to be critical how much new ice grows over the next month on the Siberian side to replace the ice that has migrated West. Are we going to have much of the thin ice on the Atlantic side of the Laptev Sea melted out and exposed to peak insolation by around the Summer solstice?


You must be psychic. This just appeared in my mail box:

Winter sea ice export from the Laptev Sea preconditions the local summer sea ice cover
 ([url]http://www.the-cryosphere-discuss.net/tc-2017-28/[/url])
Received: 27 Feb 2017 – Accepted for review: 11 Mar 2017 – Discussion started: 15 Mar 2017

Abstract: Recent studies based on satellite observations have shown that there is a high statistical connection between the late winter (Feb-May) sea ice export out the Laptev Sea, and the ice coverage in the following summer. By means of airborne sea ice thickness surveys made over pack ice areas in the southeastern Laptev Sea, we show that years of offshore directed sea ice transport have a thinning effect on the late winter sea ice cover, and vice versa. Once temperature rise above freezing, these thin ice zones melt more rapidly and hence, precondition local anomalies in summer sea ice cover. The preconditioning effect of the winter ice dynamics for the summer sea ice extent is confirmed with a model sensitivity study where we replace the inter-annual summer atmospheric forcing by a climatology. In the model, years with high late winter sea ice export always result in a reduced sea ice cover, and vice versa. We conclude that the observed tendency towards an increased ice export further accelerates ice retreat in summer. The mechanism presented in this study highlights the importance of winter ice dynamics for summer sea ice anomalies in addition to atmospheric processes acting on the ice cover between May and September. Finally, we show that ice dynamics in winter not only precondition local summer ice extent, but also accelerate fast ice decay.


Am I too early announcing the Northern Sea Route will be completely open again this year?  ;)
Title: Re: The 2017 melting season
Post by: seaicesailor on March 15, 2017, 10:42:45 AM
But wasn't kind of obvious from these past years? We can pick the paper, find/replace Laptev by Beaufort and submit a new paper... ;P
Just kidding, maximum respect to their work
Title: Re: The 2017 melting season
Post by: Gray-Wolf on March 15, 2017, 10:58:46 AM
This 'period of transition' is occurring far faster than science can respond? We are seeing 'Deniers' running with the 'weather cost as much Arctic ice as warming' paper whilst we sit at the tail end of the Meteorological winter over the basin we have just seen?

I'm sure that once 'ice free' we will still be seeing papers about a 'slow transition' and why this is how things will be?

These days I always find myself checking the study period and if it includes data from before the mid noughties I consider it dated by the changes we have seen to the system since?

When we look at the troposphere/Stratosphere over the basin this past winter and compare that to weathers over winter from the 90's can we compare them? Is there 'continuation' across that time or is 'weather/circulation' now too altered for a like for like comparison? So how does this new paper advance understanding of the future or should it be treated as a historical document looking at the workings of 'The Old Arctic'?
Title: Re: The 2017 melting season
Post by: Shared Humanity on March 15, 2017, 01:53:02 PM

Am I too early announcing the Northern Sea Route will be completely open again this year?  ;)

No.

I would be shocked if the Northern Sea Route doesn't open this year and would not be surprised if it opened very early.
Title: Re: The 2017 melting season
Post by: Apocalypse4Real on March 15, 2017, 02:06:25 PM
The Central Arctic Basin has fractured from the sea ice edge to 90 N in the last week. You will need to download and zoom the images to see the full effects. No time to crop and post.

This ice is a mess and moving in troubling ways.
Title: Re: The 2017 melting season
Post by: Shared Humanity on March 15, 2017, 02:20:49 PM
This 'period of transition' is occurring far faster than science can respond? We are seeing 'Deniers' running with the 'weather cost as much Arctic ice as warming' paper whilst we sit at the tail end of the Meteorological winter over the basin we have just seen?


Someone needs to explain to them that this "weather" (a pattern we have watched emerge for a decade) is not weather. It is called "Climate Change" and I believe more or less permanent. These low pressure systems, often emerging over the Gulf Stream and then racing up into the North Atlantic, east of Greenland and spinning into the Barents and Arctic Ocean are becoming more and more frequent. They have caused very violent weather, entire seasons actually, in the British Isles and are decimating Arctic Ice. One frequent feature of this is a high pressure that sets up over Greenland, just as we are seeing in this forecast. IIRC, these cyclone cannons are occurring in every season but I could be wrong about that.
Title: Re: The 2017 melting season
Post by: Pmt111500 on March 15, 2017, 02:38:14 PM
Someone needs to explain to them that this "weather" (a pattern we have watched emerge for a decade) is not weather.
Ok.
"This is not normal weather. In fact all the weather since 1998 hasn't been. Umm. We only see it now since..."
Title: Re: The 2017 melting season
Post by: romett1 on March 15, 2017, 03:37:48 PM
Ice drift forecast for tomorrow, Mar 16. Fram export same as today.
Image: https://www7320.nrlssc.navy.mil/hycomARC/arctic.html
Title: Re: The 2017 melting season
Post by: jdallen on March 15, 2017, 04:36:02 PM
Ice drift forecast for tomorrow, Mar 16. Fram export same as today.
Image: https://www7320.nrlssc.navy.mil/hycomARC/arctic.html
And there we have 10-15000 KM2/day of MYI getting drop-kicked out of the Arctic.
Title: Re: The 2017 melting season
Post by: Pmt111500 on March 15, 2017, 05:10:41 PM
Ice drift forecast for tomorrow, Mar 16. Fram export same as today.
Image: https://www7320.nrlssc.navy.mil/hycomARC/arctic.html
Hey Ho , lets go! That's just fycked yp and totally agaimst whatever we were taught of arctic winter.
Title: Re: The 2017 melting season
Post by: gerontocrat on March 15, 2017, 05:44:28 PM
Weather-forecast.com says conditions favourable for export for next 4 to 6 days.

Never a dull monent.
Title: Re: The 2017 melting season
Post by: tzupancic on March 15, 2017, 10:45:22 PM
Does anyone have any comments on the paper that came out on Monday in Nature Climate Change, "Influence of high-latitude atmospheric circulation changes on summertime Arctic sea ice". http://www.nature.com/nclimate/journal/vaop/ncurrent/abs/nclimate3241.html (http://www.nature.com/nclimate/journal/vaop/ncurrent/abs/nclimate3241.html)

The authors propose that a substantial amount of the recently observed summer decline in Arctic Sea Ice has been driven by natural variation in atmospheric circulation. "The Arctic has seen rapid sea-ice decline in the past three decades, whilst warming at about twice the global average rate. Yet the relationship between Arctic warming and sea-ice loss is not well understood. Here, we present evidence that trends in summertime atmospheric circulation may have contributed as much as 60% to the September sea-ice extent decline since 1979. A tendency towards a stronger anticyclonic circulation over Greenland and the Arctic Ocean with a barotropic structure in the troposphere increased the downwelling longwave radiation above the ice by warming and moistening the lower troposphere. Model experiments, with reanalysis data constraining atmospheric circulation, replicate the observed thermodynamic response and indicate that the near-surface changes are dominated by circulation changes rather than feedbacks from the changing sea-ice cover. Internal variability dominates the Arctic summer circulation trend and may be responsible for about 30–50% of the overall decline in September sea ice since 1979."
Title: Re: The 2017 melting season
Post by: Jim Hunt on March 15, 2017, 10:57:01 PM
Does anyone have any comments on the paper that came out on Monday in Nature Climate Change


I have a whole article on the topic, albeit with the emphasis thus far on the reporting of the paper rather than the substance of it:

http://GreatWhiteCon.info/2017/03/is-arctic-ice-loss-driven-by-natural-swings/ (http://GreatWhiteCon.info/2017/03/is-arctic-ice-loss-driven-by-natural-swings/)

All this excitement in the Twittosphere and elsewhere leads one to wonder whether Ding, Schweiger et al. saw (or should have seen?) all this coming, and if so what might have been done differently? In any event this story is set to run and run and run and……
Title: Re: The 2017 melting season
Post by: Cid_Yama on March 15, 2017, 11:05:40 PM
Went to look, and sure enough, this is a featured paper at WUWT where it's being sold as confirming natural cycles are responsible, not anthropogenic causes.

Expect to get repeatedly battered by deniers with this paper.  They've been given their marching orders.

See up thread for comments.   
Title: Re: The 2017 melting season
Post by: Archimid on March 15, 2017, 11:19:32 PM
I started the following thread to funnel the important discussion brought by tzupancic away from the melting season 2017 thread.

http://forum.arctic-sea-ice.net/index.php/topic,1920.0.html (http://forum.arctic-sea-ice.net/index.php/topic,1920.0.html)
Title: Re: The 2017 melting season
Post by: Bob Wallace on March 15, 2017, 11:32:50 PM
These low pressure systems, often emerging over the Gulf Stream and then racing up into the North Atlantic, east of Greenland and spinning into the Barents and Arctic Ocean are becoming more and more frequent.

Is there a site that is keeping frequency/strength storm data?

Title: Re: The 2017 melting season
Post by: VeliAlbertKallio on March 16, 2017, 01:04:54 AM
Central Arctic sector between North Pole and Laptev Sea shows very aggressive break up of sea ice with sun now increasingly warming dark leads: https://worldview.earthdata.nasa.gov/?p=arctic&l=MODIS_Aqua_CorrectedReflectance_TrueColor,MODIS_Terra_CorrectedReflectance_TrueColor,Coastlines,Reference_Labels(hidden),Reference_Features(hidden)&t=2017-03-15&z=3&v=-255904.37716371025,955877.8613822464,6239.622836289753,1120997.8613822465
Title: Re: The 2017 melting season
Post by: Tigertown on March 16, 2017, 01:15:20 AM
No doubt about movement in the Fram.
13th-15th
CLICK IMAGE
(http://)
Title: Re: The 2017 melting season
Post by: DrTskoul on March 16, 2017, 01:21:46 AM
No doubt about movement in the Fram.
13th-15th
CLICK IMAGE
(http://)

Those are some pretty old looking does saying bye bye...
Title: Re: The 2017 melting season
Post by: magnamentis on March 16, 2017, 01:23:58 AM
No doubt about movement in the Fram.
13th-15th
CLICK IMAGE
(http://)

this looks like the output of a rock grinder, except for the white instead of grey :-( those big floes must be quite thick from the locks and considering they were not yet entirely grinded.
Title: Re: The 2017 melting season
Post by: Archimid on March 16, 2017, 01:38:49 AM
That big floe turning the corner seems to move a longer distance from 14 to 15 than from 13 to 14. I wonder if that is an artifact of the images or is it actual acceleration of the floe.
Title: Re: The 2017 melting season
Post by: Tigertown on March 16, 2017, 02:47:57 AM
That big floe turning the corner seems to move a longer distance from 14 to 15 than from 13 to 14. I wonder if that is an artifact of the images or is it actual acceleration of the floe.

It looks like the wind had picked up about that time, so it probably actually accelerated.
Title: Re: The 2017 melting season
Post by: tzupancic on March 16, 2017, 05:26:01 AM
Regarding the discussion of fundamental drivers of the observed Arctic Sea Ice melt, thanks to Archimid for establishing a separate thread to discuss emerging scientific insight into the fundamentals of the melt.

Those who are interested should check out the new "Arctic Sea Ice Changes: Natural Variation vs human influence" discussion thread.

The discussion begins with the paper published this week in Nature Climate Change "Influence of high-latitude atmospheric circulation changes on summertime Arctic sea ice"

Title: Re: The 2017 melting season
Post by: epiphyte on March 16, 2017, 05:47:49 AM
But wasn't kind of obvious from these past years?

The response to your rhetorical interrogatory is tentatively in the affirmative, with the caveat that the imputation of any causal relationship between export of ice from the arctic and subsequent paucity of arctic ice is necessarily to be regarded as speculative until recognized in an adequately polysyllabic exposition of...

(As Basil Fawlty would have it)

...Mastermind special subject - "The Bleedin' Obvious!"


...
Title: Re: The 2017 melting season
Post by: Tigertown on March 16, 2017, 06:23:05 AM
The ice disposal at work.
Notice how the whole front drops back toward the end of the run.  10th-15th
(http://)
Title: Re: The 2017 melting season
Post by: oren on March 16, 2017, 07:24:25 AM
The Kara retreat has started to materialize. And that red stain (the PIOMAS blob) is still inching its way towards the Fram and oblivion.
Title: Re: The 2017 melting season
Post by: Lord M Vader on March 16, 2017, 08:10:41 AM
Is there an artefact or is the ice in Kara and Laptev "thickening"? Look at the color change between those days, the 10-15.
Title: Re: The 2017 melting season
Post by: jdallen on March 16, 2017, 08:21:52 AM
Is there an artefact or is the ice in Kara and Laptev "thickening"? Look at the color change between those days, the 10-15.
I don't see it LMV; at least, I don't see anything that stands out enough to my eye to consider it significant.
Title: Re: The 2017 melting season
Post by: DrTskoul on March 16, 2017, 08:42:16 AM
Cloud effects? 
Title: Re: The 2017 melting season
Post by: Lord M Vader on March 16, 2017, 08:54:13 AM
Jdallen: the ice color change from a green tone to a more yellow one, which should imply a thickening of the ice. This is more visible for the 14-15th in the sequence. As DrTskoul says, it could be due to cloud effects which seems likely as I have hard to see that the ice would thicken that much over a few days. Of course, maybe compaction and strong winds might do the trick but doesn't seem likely.
Title: Re: The 2017 melting season
Post by: seaicesailor on March 16, 2017, 10:46:12 AM
The ECMWF has entered into loop mode and predicts for day 10 another bomb storm entering the Barents and displaying similar circulation to the current one about to mess things up.
Everything can change but worth keeping an eye.
In the Pacific side all seems quiet and nice except for the fact that ACNFS is foreseeing an activation of Bering inflow, probably due to persistent lows over Aleutians (will post animation later)
Title: Re: The 2017 melting season
Post by: Gray-Wolf on March 16, 2017, 10:58:31 AM
956mb over brittle ,thin ice??? Surely this cannot be a good start to the season!

Temps may not be melt season temps but the lowest of the winter temps are now behind us so the ice will be starting to warm up along with the rest of the basin.

My concerns are that we have changed from a system where we had 'down time' over winter ( and could leave the forum until melt season began) to a system where winter is more important than the weathers over summer?

If we see another dreadful summer for melt yet see ice finish in the bottom three then will it not signal we have flipped into a very different beastie over the Arctic Basin?
Title: Re: The 2017 melting season
Post by: Tigertown on March 16, 2017, 11:50:53 AM
You have to remember also what that warmer water in the Barents is capable of doing when it gets disturbed. It has been building back up, waiting to get moved around again.


BTW, here is a look at SMOS.
(http://)
Title: Re: The 2017 melting season
Post by: seaicesailor on March 16, 2017, 12:16:12 PM
I wouldn't count with that 956mb low... just mentioned to keep an eye. It is still in fantasy-land. Peobably the general circulation will hold though.
The 970mb storm just hitting the door is nasty enough
Title: Re: The 2017 melting season
Post by: pauldry600 on March 16, 2017, 12:57:09 PM
I think this melt season will be the lowest on record.

My head tells me it will easily break the record but then when i read all your posts on things i cant even begin to understand i feel a slight break of the record will happen.

Maybe the mins will just get slightly lower each year for a decade or so.
Title: Re: The 2017 melting season
Post by: Shared Humanity on March 16, 2017, 03:21:07 PM
Look how tight the Isobars are over the Fram!
Title: Re: The 2017 melting season
Post by: romett1 on March 16, 2017, 03:43:27 PM
Weather-forecast.com says conditions favourable for export for next 4 to 6 days.

Never a dull monent.

Not surprisingly, ice drift estimate for tomorrow, Mar 17. There are also strong 15 - 18 m/s winds east of Svalbard, so export in two places.
Image: https://www7320.nrlssc.navy.mil/hycomARC/arctic.html
Title: Re: The 2017 melting season
Post by: 6roucho on March 16, 2017, 04:10:07 PM
That big floe turning the corner seems to move a longer distance from 14 to 15 than from 13 to 14. I wonder if that is an artifact of the images or is it actual acceleration of the floe.
Venturi effect?
Title: Re: The 2017 melting season
Post by: JimboOmega on March 16, 2017, 10:11:30 PM
Meanwhile,  the heat is on... cci-reanalyzer shows the lowest anomaly to be reached for the Arctic in its current forecast window is +2.8C. 

This is especially true near Novaya Zemlya, over the Kara Sea temperatures look to be frequently above freezing and not really getting much below.

So ice pumping down the Fram and heat pumping up the eastern Atlantic side...  Perfect conditions for the start of spring.
Title: Re: The 2017 melting season
Post by: Jim Williams on March 17, 2017, 12:48:01 AM
<snip, you're not paying attention>
Title: Re: The 2017 melting season
Post by: Cid_Yama on March 17, 2017, 03:33:25 AM
Antarctic Sea Ice is doing what the Arctic sea ice did this last fall and winter.

https://seaice.uni-bremen.de/data/amsr2/today/extent_s_running_mean_amsr2_regular.png
Title: Re: The 2017 melting season
Post by: Tigertown on March 17, 2017, 03:48:55 AM
Antarctic Sea Ice is doing what the Arctic sea ice did this last fall and winter.

https://seaice.uni-bremen.de/data/amsr2/today/extent_s_running_mean_amsr2_regular.png

The ol' insolation batteries got charged a little too well. I look for it to happen again in the Arctic later this year to a greater degree than last year. You can already see the heat building in the oceans surrounding the Arctic by looking at the anomalies at high lats. on both sides. Will get worse when more waters are open.
                                                                                                                               

What do the failing predictive models have to do with the melting season?

That has been moved to another thread already, thanks to Archimid, who is becoming quite a useful contributor on this forum.
Title: Re: The 2017 melting season
Post by: romett1 on March 17, 2017, 10:41:37 AM
Meanwhile,  the heat is on... cci-reanalyzer shows the lowest anomaly to be reached for the Arctic in its current forecast window is +2.8C. 

This is especially true near Novaya Zemlya, over the Kara Sea temperatures look to be frequently above freezing and not really getting much below.

So ice pumping down the Fram and heat pumping up the eastern Atlantic side...  Perfect conditions for the start of spring.

Latest GFS - maximum anomaly per day until next Friday. FDD (Freezing Degree Days for 80N+) anomaly is now about 1,540 since September (last year it was about 950 at the same time).
I guess it's going to 1,600 level next week.
Title: Re: The 2017 melting season
Post by: rboyd on March 17, 2017, 06:36:30 PM
My understanding is that the anomaly tends to be higher in winter and less in the summer. Will be interesting to see if it persists at a high level during the summer, would reflect the increased albedo effect of more open water earlier in the season (versus the offsetting increased cloud cover assumed in many of the climate models).
Title: Re: The 2017 melting season
Post by: Archimid on March 17, 2017, 06:49:08 PM
My understanding is that the anomaly tends to be higher in winter and less in the summer.
Yes, but a persistent 4C+ anomaly through the whole winter is new to the data set. Also summer temperatures are limited by the ice. The anomalies during summer will not be this high until sufficient ice is gone.
Title: Re: The 2017 melting season
Post by: rboyd on March 17, 2017, 08:22:01 PM
Could start to happen locally on the periphery, like the Kara Sea, ESS, and Beaufort, if the ice there goes early enough in the season. Would that then set up some significant temperature differentials with the ice covered areas?
Title: Re: The 2017 melting season
Post by: JimboOmega on March 17, 2017, 09:01:28 PM
My understanding is that the anomaly tends to be higher in winter and less in the summer.
Yes, but a persistent 4C+ anomaly through the whole winter is new to the data set. Also summer temperatures are limited by the ice. The anomalies during summer will not be this high until sufficient ice is gone.

Right; ice and water together have to have a temperature around 0C; pumping more heat in just turns more of the ice to water. So summer anomalies can't really go up until the ice all melts.

For this reason, in the summer, we tend to look more at the 925 hPa (or is it mb? I forget) temperature forecasts, to get a sense of the warmth being transported in. By not looking right at the surface we can see how anomalously warm it is.
Title: Re: The 2017 melting season
Post by: magnamentis on March 18, 2017, 12:08:14 AM
Could start to happen locally on the periphery, like the Kara Sea, ESS, and Beaufort, if the ice there goes early enough in the season. Would that then set up some significant temperature differentials with the ice covered areas?

as long as there is ice, temps won't go much above zero in that region, it's the laws of physics at play here and it has been well explained in this forum while i don't remember exactly where it was, perhaps you gonna find it with the help of the search function, else google is your friend :-)
Title: Re: The 2017 melting season
Post by: rboyd on March 18, 2017, 06:05:35 AM
Thanks for the great responses!
Title: Re: The 2017 melting season
Post by: romett1 on March 18, 2017, 10:36:44 AM
The ECMWF has entered into loop mode and predicts for day 10 another bomb storm entering the Barents and displaying similar circulation to the current one about to mess things up.
Everything can change but worth keeping an eye.

Latest GFS (Climate Reanalyzer) is showing even higher max anomalies for Arctic.
Warmest areas Laptev, Kara and ESS. Also pressure 963 forecasted near Svalbard and FJL for next Saturday. Of course, it's pretty far, but still worth watching.
Title: Re: The 2017 melting season
Post by: CalamityCountdown on March 18, 2017, 04:33:37 PM
Shouldn't the title of this thread be "The 2017 Melting Equilibrium Month"? Based on the NSIDC 5 day average, it appears that "melting season" did not get started until about the 27th during the last  two years
Title: Re: The 2017 melting season
Post by: Jim Hunt on March 18, 2017, 07:05:57 PM
Yet another Arctic cyclone drops below 970 hPa MSLP. The synoptic chart is from 1800Z last night:

http://GreatWhiteCon.info/2017/03/facts-about-the-arctic-in-march-2017/#comment-219974 (http://GreatWhiteCon.info/2017/03/facts-about-the-arctic-in-march-2017/#comment-219974)
Title: Re: The 2017 melting season
Post by: DrTskoul on March 18, 2017, 07:10:31 PM
How many cyclones below 970 have we had this winter? I 've lost count...
Title: Re: The 2017 melting season
Post by: Jim Hunt on March 18, 2017, 07:18:40 PM
Shouldn't the title of this thread be "The 2017 Melting Equilibrium Month"?

Traditionally we only have a "freezing" and then a "melting" thread each year.

YMMV of course, but I reckon the loss of over 200k in two days could reasonably be described as "melting". Mind you this thread was started quite a while ago!
Title: Re: The 2017 melting season
Post by: Shared Humanity on March 18, 2017, 08:19:40 PM
Where that intense low is currently sitting and where the ice drift map is showing rapid ice movement, there is nothing resembling true ice pack. All of the ice under this low is highly fragmented and less than 2 meters thick, much of it only 1 meter thick. With warm water intrusion from the Barents, a nearly nonexistent halocline, this summer on the Atlantic side could be horrifying.
Title: Re: The 2017 melting season
Post by: rboyd on March 18, 2017, 08:30:03 PM
Unrelenting positive anomalies on the Russian side of the Arctic to March 26th from climate reanalyzer, not good for thickening the ice. Periods of near zero and above in the Kara Sea.
Title: Re: The 2017 melting season
Post by: Tigertown on March 18, 2017, 09:04:24 PM
1000hpa warm air intrusion varying between +1oC and +2.2oC.
Starting now(left side) progressing in 3 hour intervals, left to right, and top down.
(http://)
Title: Re: The 2017 melting season
Post by: Clenchie on March 18, 2017, 09:46:21 PM
Thanks Tigertown, a picture paints a thousand words.
Title: Re: The 2017 melting season
Post by: Tigertown on March 19, 2017, 04:38:16 AM
Among other places, it looks like there is melting and thinning out of ice within parts of the CAA.
(http://)
Title: Re: The 2017 melting season
Post by: seaicesailor on March 19, 2017, 06:06:06 AM
Among other places, it looks like there is melting and thinning out of ice within parts of the CAA.
(http://)
With current temps there, I doubt we are seeing any thinning out in CAA. More like the usual thickening-in I'd say.
Kara otoh is going south pretty quickly this year.
Title: Re: The 2017 melting season
Post by: Pmt111500 on March 19, 2017, 06:15:19 AM
Among other places, it looks like there is melting and thinning out of ice within parts of the CAA.
(http://)

With current temps there, I doubt we are seeing any thinning out in CAA. More like the usual thickening-in I'd say.
Kara otoh is going south pretty quickly this year.

Oh, is the River Ob already in spring and flowing fast to Kara sea? The bay there could be an indication of that. The zero-degree fresh water from the river taking a toll on the -1 degree ice on the bay, possibly? The bay is somewhat brackish : www.researchgate.net/figure/283097363_fig3_Figure-4-Left-salinity-PSU-of-Kara-Sea-and-the-Gulf-of-Ob-in-summer-climatic-atlas (http://www.researchgate.net/figure/283097363_fig3_Figure-4-Left-salinity-PSU-of-Kara-Sea-and-the-Gulf-of-Ob-in-summer-climatic-atlas)
Title: Re: The 2017 melting season
Post by: Tigertown on March 19, 2017, 06:40:30 AM
Among other places, it looks like there is melting and thinning out of ice within parts of the CAA.
With current temps there, I doubt we are seeing any thinning out in CAA. More like the usual thickening-in I'd say.

Something changed around the 11th. Maybe that the ice is such slush that it is moving and compacting elsewhere with the wind.
Compare the 10th(left) with the 18th(right)
(http://)
Title: Re: The 2017 melting season
Post by: romett1 on March 19, 2017, 07:40:35 AM
As we speak, warm winds have reached to Laptev Sea. Temp +1.1 °C and wind 13 m/s.
That is 9:00 UTC according to earth.nullschool.
Title: Re: The 2017 melting season
Post by: romett1 on March 19, 2017, 09:44:32 AM
Latest GFS shows higher anomalies for Arctic persist (numbers are now average per day).
Warmest areas Laptev, Kara and ESS. Kara and Laptev seem to be constantly "warm" until next Sunday.
Title: Re: The 2017 melting season
Post by: Neven on March 19, 2017, 10:15:48 AM
The retreat south of Novaya Zemlya is caused by winds and is bound to continue given the current forecast, with lows stationed over the Siberian side of the Arctic.

I've just called the maximum (http://neven1.typepad.com/blog/2017/03/lowest-maximum-on-record-again.html) on the ASIB, and posted an animation of the ClimateReanalyzer GFS temp anomaly forecast for the coming week:

(http://neven1.typepad.com/.a/6a0133f03a1e37970b01b8d26c43f4970c-800wi)
Title: Re: The 2017 melting season
Post by: Red on March 19, 2017, 11:23:25 AM
Among other places, it looks like there is melting and thinning out of ice within parts of the CAA.

With current temps there, I doubt we are seeing any thinning out in CAA. More like the usual thickening-in I'd say.


Something changed around the 11th. Maybe that the ice is such slush that it is moving and compacting elsewhere with the wind.
Compare the 10th(left) with the 18th(right)
(http://)

 The Canadian ice service (CIS) shows mostly old ice and medium FYI in the western CAA.
http://ice-glaces.ec.gc.ca/prods/WIS56SD/20170313180000_WIS56SD_0009363745.pdf (http://ice-glaces.ec.gc.ca/prods/WIS56SD/20170313180000_WIS56SD_0009363745.pdf)
 With the eastern CAA showing mostly medium FYI and some old ice showing up in the western edge.
The CIS definition of old ice: Sea ice which has survived at least one summer's melt.
glaces.ec.gc.ca/prods/WIS55SD/20170313180000_WIS55SD_0009363789.pdf

PS I can't seem to figure out how to capture the image.
Title: Re: The 2017 melting season
Post by: FishOutofWater on March 19, 2017, 01:41:20 PM
The retreat south of Novaya Zemlya is caused by winds and is bound to continue given the current forecast, with lows stationed over the Siberian side of the Arctic.

I've just called the maximum ([url]http://neven1.typepad.com/blog/2017/03/lowest-maximum-on-record-again.html[/url]) on the ASIB, and posted an animation of the ClimateReanalyzer GFS temp anomaly forecast for the coming week:

([url]http://neven1.typepad.com/.a/6a0133f03a1e37970b01b8d26c43f4970c-800wi[/url])


The U.S. CFS model, the long range extension of the GFS predicts this atmospheric circulation pattern will continue through the spring so that north Siberian temperatures will average well above normal for months. Apparently, the ocean heat patterns are driving this general circulation pattern.

This portends a catastrophic summer for sea ice and Siberian permafrost.

Title: Re: The 2017 melting season
Post by: Buddy on March 19, 2017, 02:25:43 PM
This portends a catastrophic summer for sea ice and Siberian permafrost.

Eastern continental Europe....+....northwestern Russia has had a warm spring.  Someone else has already made posts of the German drought this winter and spring.

The risk of SIGNIFICANT wildfires in northern Russia and especially northwestern Russia (including Moscow) is there are waiting.  The conditions are ripe.....now all that is needed is the right (wrong) weather patterns.

Additional wildfires.....like those in 2010.....is going to feed the already ravenous feedback effects.   We continue to take the "next step" into what everyone here KNEW is happening.  The only thing we don't know each year is (1) where is it going to be bad this year, and (2) how bad is bad going to be THIS YEAR?

Arctic ice likely heading for a new record low.  How low?  Is it going to be 5% below the 2012 record....or 15% below the prior record low?

Next decade likely to be "eye-popping" on several fronts:   Ice, temps, wildfires, etc.

The next week along the northern Russian coast could be an opening dagger for the ice melt season this year.

Nighttime temps in Russia are remaining high.....with a continued lack of "new record low temps".  The new record high temps haven't been incredibly high.....it's the LACK of new record low temps....they are becoming an endangered species.  Russia has 2 (two) new record low temps in the country so far this month.  They have 5 months THIS DECADE when they have had 10 or fewer new record low daily temps for any single month....and those have come over the last 40 months.  The entire decade of 2000 - 2009 had only 2 instances where a single month had 10 or few new record low temps. 

Going to be a crazy climate year....and a crazy climate decade.  Just make sure you remind people who has been lying over the past 10 - 30 years as this continues to unfold.

Title: Re: The 2017 melting season
Post by: FishOutofWater on March 19, 2017, 04:05:00 PM
The atmosphere is efficiently removing the cold air from the Arctic and eliminating the cold by ramming it over the northwest Pacific and the NW Atlantic. This has happened because the Pacific decadal oscillation has shifted to the warm phase and the overturning circulation in the north Atlantic has gone into its more active mode. This PDO (or IPO) pattern expands the jet stream southward over the Pacific ocean. It also brings more heat from the Atlantic to central and northern Europe.

This all adds up to a warm early spring for northern Eurasia. And once in place it will be amplified by early snow loss and increasing heat uptake by the bare ground and open ocean.

Yes, expect a bad fire season in Russia and Siberia to start early and for the soot to amplify the rate of snow melt and ice loss.

Here are a few panels showing what I described above from ECMWF model forecast of the circulation and temperature patterns the next 10 days. Thanks to Levi at Tropicaltidbits.com.

Note the general aspects of the circulation pattern will continue all spring if the Euro and American models are getting it right. And I'm pretty sure they are because they are picking up something huge - a strong jet stream and extreme ocean heat in the north Atlantic and subpolar seas.

Title: Re: The 2017 melting season
Post by: Andreas T on March 19, 2017, 04:48:01 PM
Among other places, it looks like there is melting and thinning out of ice within parts of the CAA.
With current temps there, I doubt we are seeing any thinning out in CAA. More like the usual thickening-in I'd say.

Something changed around the 11th. Maybe that the ice is such slush that it is moving and compacting elsewhere with the wind.
Compare the 10th(left) with the 18th(right)
(http://)
As has  been pointed out by others care has to be taken when interpreting the AMSR charts.
The attached image is IR band 31 https://go.nasa.gov/2nSrmIT (https://go.nasa.gov/2nSrmIT) of 19th and there is no sign of openings or recent openings in the Parry channel area. South of Banks island the purple hue shows thinner ice (warmer surface) this is what ice looks which has formed in the last weeks. Open water would show in orange in my colour scale setting 227 -273K
Talking about "slush" there has no credibility.
Again the appearance of lowered ice concentration coincides with clouds.
Title: Re: The 2017 melting season
Post by: Jim Hunt on March 19, 2017, 04:49:10 PM
I can't seem to figure out how to capture the image.


Try using the .GIF versions instead of the .PDFs

Here's the one you mention:

http://GreatWhiteCon.info/resources/arctic-regional-graphs/northwest-passage/ (http://GreatWhiteCon.info/resources/arctic-regional-graphs/northwest-passage/)

Here's how the brown bits got there:

http://GreatWhiteCon.info/2016/09/is-the-northwest-passage-freezing-or-melting/ (http://GreatWhiteCon.info/2016/09/is-the-northwest-passage-freezing-or-melting/)
Title: Re: The 2017 melting season
Post by: Red on March 19, 2017, 04:57:30 PM
I can't seem to figure out how to capture the image.


Try using the .GIF versions instead of the .PDFs

Here's the one you mention:

[url]http://GreatWhiteCon.info/resources/arctic-regional-graphs/northwest-passage/[/url] ([url]http://GreatWhiteCon.info/resources/arctic-regional-graphs/northwest-passage/[/url])

Here's how the brown bits got there:

[url]http://GreatWhiteCon.info/2016/09/is-the-northwest-passage-freezing-or-melting/[/url] ([url]http://GreatWhiteCon.info/2016/09/is-the-northwest-passage-freezing-or-melting/[/url])

Thanks Jim I'll give that  a go next I post.
Title: Re: The 2017 melting season
Post by: Tigertown on March 19, 2017, 05:34:37 PM
Talking about "slush" there has no credibility

Ok, slush was probably an overstatement. However, the shape that the ice is in for this time of year has made it more mobile and at the whim of wind and current. When it compacts in one place, the concentration goes down in another. I don't recall saying anything about open water. The concentration went down by a percentage*, which I am sure many including myself thought to be worth mentioning. It shouldn't do that so easily right now. It simply isn't going to hold together once it really comes under any pressure, and then it will be "slush."


* In that one area after the 10th of the month, lasting until the current date.
Title: Re: The 2017 melting season
Post by: bbr2314 on March 19, 2017, 05:34:55 PM
The retreat south of Novaya Zemlya is caused by winds and is bound to continue given the current forecast, with lows stationed over the Siberian side of the Arctic.

I've just called the maximum ([url]http://neven1.typepad.com/blog/2017/03/lowest-maximum-on-record-again.html[/url]) on the ASIB, and posted an animation of the ClimateReanalyzer GFS temp anomaly forecast for the coming week:

([url]http://neven1.typepad.com/.a/6a0133f03a1e37970b01b8d26c43f4970c-800wi[/url])


The U.S. CFS model, the long range extension of the GFS predicts this atmospheric circulation pattern will continue through the spring so that north Siberian temperatures will average well above normal for months. Apparently, the ocean heat patterns are driving this general circulation pattern.

This portends a catastrophic summer for sea ice and Siberian permafrost.


I wonder if enhanced Siberian snowcover is playing a part in this? Vastly more open Arctic Ocean = +++Siberian snowfall, but even when we see temps average much colder than normal over parts of the region as we did last fall, that is derived from anomalously *early* snowcover and not radiative cooling.

Perhaps the feedback resulting in increasing NHEM autumnal snowcover (especially in Eurasia) contributes directly to the ++++anomalies seen over Siberia during spring/summer normally? The insulating and anomalously thick snowpack must mitigate the ability of permafrost to reform, perhaps locking in some of the heat accumulated by the ground during summer as well, resulting in a ready-to-bake northern tier of Russia as soon as the snowcover melts in the spring.
Title: Re: The 2017 melting season
Post by: Gray-Wolf on March 19, 2017, 05:47:32 PM
This would by my thinking too bbr2314?

I might even be tempted into thinking that parts of ESS/Kara/Barentsz had some pretty slushy surface conditions over October that may have seeded freezing over summer warmed waters locking that heat in too?

If we lose the W.Siberian snow as early as other years then all it will have served to do is rip the vortex off its keel and throw arctic plunges around the lower latitudes emptying the basin of cold for WAA to replace.

In other words it is another positive feedback even if it involves 'Snow'..........
Title: Re: The 2017 melting season
Post by: Archimid on March 19, 2017, 06:21:16 PM
Look at the snow cover graphs on ASIG Link: https://www.ccin.ca/home/ccw/snow/current (https://www.ccin.ca/home/ccw/snow/current)

The first two are the Snow Cover Extent for North America and Eurasia. Notice that they are trending low but within variation.

The second two are of the Snow Water Equivalent, which I interpret as the thickness of the snow pack. Notice that is trending very high.

 Even if there is thicker snow cover, the snow extent favors lower albedo.

Title: Re: The 2017 melting season
Post by: Neven on March 19, 2017, 06:27:41 PM
That Snow Water Equivalent graphs has been trending high for as long as I can remember. I'm not sure, but I think there's something wrong with it.
Title: Re: The 2017 melting season
Post by: jai mitchell on March 19, 2017, 07:25:22 PM
I don't think so Neven, the increase is consistent with the models and warmer/wetter atmospheric circulation moving further northward
Title: Re: The 2017 melting season
Post by: Red on March 19, 2017, 07:51:16 PM
I don't think so Neven, the increase is consistent with the models and warmer/wetter atmospheric circulation moving further northward
And windier, the denser it's packed the more water it will represent when melted.
Title: Re: The 2017 melting season
Post by: bbr2314 on March 19, 2017, 09:32:10 PM
I don't think so Neven, the increase is consistent with the models and warmer/wetter atmospheric circulation moving further northward
Agreed, you can see a map of anomalies as well:

(https://www.ccin.ca/home/sites/default/files/snow/snow_tracker/plot_anom_sdep.png)
Title: Re: The 2017 melting season
Post by: crandles on March 19, 2017, 09:46:22 PM
That purple y shape seems a permanent fixture. I would suspect a period with no data for that area.

Agree warmer conditions, more moisture in atmosphere, heavier precipitation seems pretty well established.
Title: Re: The 2017 melting season
Post by: Jim Williams on March 19, 2017, 09:56:14 PM
I wonder if enhanced Siberian snowcover is playing a part in this?
Do you know the play Rosencrantz and Guildenstern Are Dead?  ( https://en.wikipedia.org/wiki/Rosencrantz_and_Guildenstern_Are_Dead )
Title: Re: The 2017 melting season
Post by: Jim Williams on March 19, 2017, 10:00:44 PM
I don't think so Neven, the increase is consistent with the models and warmer/wetter atmospheric circulation moving further northward
And windier, the denser it's packed the more water it will represent when melted.
I have to agree with this line of thought.  For now it is Warm Arctic, Cold Continents....complete with snow.  I do not see new ice sheets in our immediate future.

Title: Re: The 2017 melting season
Post by: Neven on March 19, 2017, 10:15:02 PM
That purple y shape seems a permanent fixture. I would suspect a period with no data for that area.

Which is why I don't trust that Snow Water Equivalent graph. There's no way there's so much snow in the Himalayas, all of the time.

Of course, there's more precipitation, and so more snow extent and snow depth, but not so much to make that trend line get off the charts. There are quite a few zones with negative anomalies as well.

But, anyway, it's a conclusion I reached last year or the year before. I may be wrong.
Title: Re: The 2017 melting season
Post by: Tigertown on March 19, 2017, 10:48:55 PM
@Neven
It might be worth looking into, as there have been so many severe avalanches in that area lately. I would google it myself, but I am on the way out to run errands.
Title: Re: The 2017 melting season
Post by: Neven on March 19, 2017, 11:37:43 PM
@Neven
It might be worth looking into, as there have been so many severe avalanches in that area lately. I would google it myself, but I am on the way out to run errands.

Yes, it might be worth looking into, but that purple area where the Himalayas are, has been on that map for as long as I can remember.

And another funny thing: Here in Austria they say there have been more avalanches in the Alps this year, because snowfall was below average. But I don't know if that's true.

Either way, whether there's a HUGE Snow Water Equivalent or not, I'm quite sure that it will all melt quite quickly. And that's the bottom line.
Title: Re: The 2017 melting season
Post by: Red on March 20, 2017, 12:08:54 AM
That purple y shape seems a permanent fixture. I would suspect a period with no data for that area.


Which is why I don't trust that Snow Water Equivalent graph. There's no way there's so much snow in the Himalayas, all of the time.

Of course, there's more precipitation, and so more snow extent and snow depth, but not so much to make that trend line get off the charts. There are quite a few zones with negative anomalies as well.

But, anyway, it's a conclusion I reached last year or the year before. I may be wrong.

Not sure if this is any help, the paper is paywalled, however it may shed some light on the subject of snow water equivalent. The locations of the test sites may play a bigger roll +/- in our new climate state then they traditionally have.
http://www.sciencedirect.com/science/article/pii/S0034425711003166Abstract (http://www.sciencedirect.com/science/article/pii/S0034425711003166Abstract)
The key variable describing global seasonal snow cover is snow water equivalent (SWE). However, reliable information on the hemispheric scale variability of SWE is lacking because traditional methods such as interpolation of ground-based measurements and stand-alone algorithms applied to space-borne observations are highly uncertain with respect to the spatial distribution of snow mass and its evolution. In this paper, an algorithm assimilating synoptic weather station data on snow depth with satellite passive microwave radiometer data is applied to produce a 30-year-long time-series of seasonal SWE for the northern hemisphere. This data set is validated using independent SWE reference data from Russia, the former Soviet Union, Finland and Canada. The validation of SWE time-series indicates overall strong retrieval performance with root mean square errors below 40 mm for cases when SWE < 150 mm. Retrieval uncertainty increases when SWE is above this threshold. The SWE estimates are also compared with results obtained by a typical stand-alone satellite passive microwave algorithm. This comparison demonstrates the benefits of the newly developed assimilation approach. Additionally, the trends and inter-annual variability of northern hemisphere snow mass during the era of satellite passive microwave measurements are shown.
Title: Re: The 2017 melting season
Post by: romett1 on March 20, 2017, 09:21:28 AM
Latest GFS (Climate Reanalyzer) shows following anomalies for Arctic until next Monday. Kara, Laptev and ESS warmest. Also ice seems to be pretty fragmented between Svalbard and North Pole after non-stop export at high speed.
Title: Re: The 2017 melting season
Post by: dosibl on March 20, 2017, 03:29:06 PM
Before we get too deep into melting season, would some of the more seasoned posters mind giving a handful of things they will be keeping an eye on over the next few months to judge how 'good' or 'bad' the melt is going?

This will be my (and I suspect some others) first melting season so it'd be nice to know what to expect in general, as well as what to watch coming from such an extreme freezing season.
Title: Re: The 2017 melting season
Post by: Jim Hunt on March 20, 2017, 03:48:49 PM
Before we get too deep into melting season, would some of the more seasoned posters mind giving a handful of things they will be keeping an eye on over the next few months to judge how 'good' or 'bad' the melt is going?


5 fingers worth to start with? Not necessarily in order of time or importance!

1. How soon melt ponds and/or open water hang around in the Beaufort Sea this year. Things started very early last year:

http://GreatWhiteCon.info/2016/04/the-beaufort-gyre-goes-into-overdrive/ (http://GreatWhiteCon.info/2016/04/the-beaufort-gyre-goes-into-overdrive/)

2. Ditto the Bering Strait and Chukchi Sea

3. Ditto the Laptev and East Siberian Seas

4. How many (and how deep, warm, wet) spring cyclones spin around the Arctic Ocean

5. How the snow melt progresses across Canada, Alaska and Siberia

Next please!
Title: Re: The 2017 melting season
Post by: seaicesailor on March 20, 2017, 04:43:20 PM
Before we get too deep into melting season, would some of the more seasoned posters mind giving a handful of things they will be keeping an eye on over the next few months to judge how 'good' or 'bad' the melt is going?


5 fingers worth to start with? Not necessarily in order of time or importance!

1. How soon melt ponds and/or open water hang around in the Beaufort Sea this year. Things started very early last year:

[url]http://GreatWhiteCon.info/2016/04/the-beaufort-gyre-goes-into-overdrive/[/url] ([url]http://GreatWhiteCon.info/2016/04/the-beaufort-gyre-goes-into-overdrive/[/url])



Suscrbe all points, emphasizing this one because for the time being weather is being favorable to Beaufort sea ice (relative to last year) .All can change in April obviously
Title: Re: The 2017 melting season
Post by: be cause on March 20, 2017, 04:49:42 PM
Hi Dosibl .. I would take a look at Cryosphere Today .. the site no longer updates , but the 'comparison' feature allows you to look at and compare the ice cover on any date/s in the satellite era .
Title: Re: The 2017 melting season
Post by: jai mitchell on March 20, 2017, 04:58:26 PM
the plunge begins:

NSIDC SIE daily values

2017,    03,  12,     14.403
2017,    03,  13,     14.370
2017,    03,  14,     14.424
2017,    03,  15,     14.407
2017,    03,  16,     14.273
2017,    03,  17,     14.242
2017,    03,  18,     14.178
2017,    03,  19,     14.180
Title: Re: The 2017 melting season
Post by: Tor Bejnar on March 20, 2017, 05:31:06 PM
Before we get too deep into melting season, would some of the more seasoned posters mind giving a handful of things they will be keeping an eye on over the next few months to judge how 'good' or 'bad' the melt is going?


5 fingers worth to start with? Not necessarily in order of time or importance!

1. How soon melt ponds and/or open water hang around in the Beaufort Sea this year. Things started very early last year:

[url]http://GreatWhiteCon.info/2016/04/the-beaufort-gyre-goes-into-overdrive/[/url] ([url]http://GreatWhiteCon.info/2016/04/the-beaufort-gyre-goes-into-overdrive/[/url])

2. Ditto the Bering Strait and Chukchi Sea

3. Ditto the Laptev and East Siberian Seas

4. How many (and how deep, warm, wet) spring cyclones spin around the Arctic Ocean

5. How the snow melt progresses across Canada, Alaska and Siberia

Next please!

I'd add:
In 3 months we'll start looking at melt ponds in the Central Arctic Basin (CAB) and wonder when the Northern Passage and NW Passage will open. Oh yes, and when will the news media notice how bad things are getting.
Title: Re: The 2017 melting season
Post by: theoldinsane on March 20, 2017, 05:52:55 PM
Before we get too deep into melting season, would some of the more seasoned posters mind giving a handful of things they will be keeping an eye on over the next few months to judge how 'good' or 'bad' the melt is going?

This will be my (and I suspect some others) first melting season so it'd be nice to know what to expect in general, as well as what to watch coming from such an extreme freezing season.

After a couple of years as mainly a lurker in this amazing forum I have hopefully learned something. My take is this:

1 Do expect the unexpected (upside or downside or flat) and don´t compare to previous years

2 Don´t do any predictions about the minimum before July

3 Realise that the Arctic ice is in a very VERY bad shape compare to 20 years ago (or even many thousands year ago)

Some says it´s all about the weather, but if the declining Arctic ice is the culprit of the weather then there is a viscious circle caused by humans emissions of GHG. There is natural variance but those are getting bigger as GHG emissions continues if I got it right.

https://hubpages.com/literature/The-Two-Degree-World

So it can happen that this years minimum will show up as the 5:th or 6:th or 7:th lowest as well as a Blue Ocean Event. I don´t know. Only time will tell.

This is both exiting and very VERY scary IMHO
 
Title: Re: The 2017 melting season
Post by: oren on March 20, 2017, 06:08:14 PM
dosibl, the most telling areas will be the Beaufort as already been said, compared to the last few years to see wether it's early or late, and the Barents/Svalbard/Atlantic front on a qualitative basis. And not on a daily basis, PIOMAS.
Title: Re: The 2017 melting season
Post by: jdallen on March 20, 2017, 06:11:40 PM
Before we get too deep into melting season, would some of the more seasoned posters mind giving a handful of things they will be keeping an eye on over the next few months to judge how 'good' or 'bad' the melt is going?

This will be my (and I suspect some others) first melting season so it'd be nice to know what to expect in general, as well as what to watch coming from such an extreme freezing season.
Lots of good suggestions from others.

My favorites:

Sea surface temperatures
General dispersion and concentration
Circulation and transport of ice in the pack
Cloud cover and albedo
Title: Re: The 2017 melting season
Post by: Pmt111500 on March 20, 2017, 06:12:24 PM

2 Don´t do any predictions about the minimum before July


I was just about to do that and happily forget asif totally after that.

I'll try to follow the spring in the big Siberian/Canadian river areas and later hoping to see some ice breaker save Santa Claus from drowning.
Title: Re: The 2017 melting season
Post by: Jontenoy on March 20, 2017, 06:15:15 PM
Hi All
This is my first blog on your wonderful site which I have been watching for nearly a year.
Today NASA announced that Greeland and Antarctic are losing 400 gigatons of ice / year. I have just calculated this as giving 2.38 mm / year height increase. Water thermal expansion + glacial and other surface ice would be in addition to this (also aquafier surface pumping). Does this seem a bit high ?
Title: Re: The 2017 melting season
Post by: Neven on March 20, 2017, 06:26:30 PM
Jontenoy, this thread is for the Arctic sea ice melting season specifically. You need to ask the question elsewhere in the Greenland or Antarctica boards.
Title: Re: The 2017 melting season
Post by: LRC1962 on March 20, 2017, 08:13:46 PM
One note of caution. Even if the melt season turns out that there is not a great melt off and therefore a conclusion could be reached that the melt season was too cold or not right for melting, the ice is still in very bad shape. On top of that the winter months are getting so much warmer and stormier that what ice hangs around and actually grows is not in very good condition. In conclusion, the Arctic ice that is there is on life support and unless we humans get our act together, the rest of the earths systems are going to change so much that the normal will not be as it was even 20 years ago.
Title: Re: The 2017 melting season
Post by: magnamentis on March 20, 2017, 08:28:09 PM
dosibl, the most telling areas will be the Beaufort

this is based on the past while it's exactly possible that the final attack on sea-ice from now on can (will) come from any (unexpected) side and chances are high that we're in for more surprises.

what i'm trying to say, sorry if i got that wrong, is, that even should the beaufort be ice-coverd in may for once (not saying it will) most ice can be eliminated from the the atlantic side and exported down fram while at he same time a bit of garlic press down CAA et voilà, almost nothing left while the rest (in this example that would be beaufort) will melt out between may and september anyways. so the key is the CAB all above 80 degrees north, the more of that goes, the lower the minimum. IMO there is no doubt that we wont' even see any kind of "ARMS" or other significant reminders below 75 degrees north this year. game on, let's see.

this is just my take on it, not saying it will or has to be, just drawing a picture (like every year) and after all
a lot became true in the past ;)

i'm looking forward to the extreme takes of "BBR" LOL.

the season will be (already is) very interesting in any case
Title: Re: The 2017 melting season
Post by: bbr2314 on March 20, 2017, 08:58:16 PM
That purple y shape seems a permanent fixture. I would suspect a period with no data for that area.


Which is why I don't trust that Snow Water Equivalent graph. There's no way there's so much snow in the Himalayas, all of the time.

Of course, there's more precipitation, and so more snow extent and snow depth, but not so much to make that trend line get off the charts. There are quite a few zones with negative anomalies as well.

But, anyway, it's a conclusion I reached last year or the year before. I may be wrong.

This graph purportedly excludes mountain snows:

(http://globalcryospherewatch.org/state_of_cryo/snow/fmi_swe_tracker.jpg)

I definitely agree it is difficult to ascertain the veracity of those Himalayan purples but a part of me thinks it is not so unlikely; it seems that any region that has sufficient latitude or elevation is now seeing more general ++snow anomalies, so perhaps with the sheer height of the Himalayas, they are a natural bulwark against AGW in that even as the snow line may or may not be rising, the amount of snow falling *above* the line is now increasing seemingly on an annual basis.

It is very important to note that *if* that is the case, changing snowcover's impact on global albedo becomes much more drastic. Increased NHEM fall snowcover is impactful on albedo but its implications aren't nearly as drastic as a blob of anomalous snowcover at a relatively low latitude that persists through spring and possibly summer. Even if the % of the Himalayas that are covered in July or August increases from 5-10% to 20-30%, that is a very sizable amount of solar input that is now being thrown off at the height of NHEM summer.

I am straying a bit far here but I wonder if the above is linked to the failure of the QBO... if there is any major wildcard besides the Arctic that has not yet been identified, I do believe it is the Himalayan snowpack, and with its location relatively close to the Equator, the impacts of changing snowfall on the planet's highest mountain range have the potential to be *very* sizable.

I am adding in the below which I found from a paper indicating summer extent is indeed increasing across the Western Himalayas quite dramatically while falling slightly over central/eastern (for large net gain). Any additional studies/links would be much appreciated!

https://www.researchgate.net/publication/260939503_11-Year_Variability_of_Summer_Snow_Cover_Extent_over_Himalayas (https://www.researchgate.net/publication/260939503_11-Year_Variability_of_Summer_Snow_Cover_Extent_over_Himalayas)

Snow is a component of the cryosphere which has played an important role in Earth energy balance. Northern hemisphere snow cover extent (SCE) has steadily decreased since 1980 and in recently the trend of SCE is sharply decreased. Because Himalaya region's shows most significant changes except for the Arctic, we analyzed this region for SCE. We used Moderate Resolution Imaging Spectroradiometer (MODIS) snow product from 2001 to 2011 in august. Analysis was made by considering some conditions (region, elevation, longitude and climate) which can affect the changes in SCE. The entire SCE in Himalaya for 11 years has steadily increased(+55,098 km2). Trends for SCE in western region has increased(+77,781km2), But trend for central and eastern have decreased -3,453 km2, -19,230km2, respectively. According to elevation increases, the ratio of snow in each study area is increased. In 30°N~35°N SCE shows increased trend, 27°N~28°N shows decreased trend. In tundra climate, trends for SCE are similar to regional analysis. whereas the result in tropical climate's trend was increased. these performed result shows different side for change of SCE depending on each condition. The result of this study were similar to the rapid decline of the northern hemisphere SCE area in recent. The result of this study can be used to help management to water budget in Central-Asia country located to Himalayas.
Title: Re: The 2017 melting season
Post by: Tigertown on March 20, 2017, 09:36:57 PM
One note of caution. Even if the melt season turns out that there is not a great melt off and therefore a conclusion could be reached that the melt season was too cold or not right for melting, the ice is still in very bad shape. On top of that the winter months are getting so much warmer and stormier that what ice hangs around and actually grows is not in very good condition. In conclusion, the Arctic ice that is there is on life support and unless we humans get our act together, the rest of the earths systems are going to change so much that the normal will not be as it was even 20 years ago.

I wanted to reply to this but wasn't sure about doing so on this thread, for fear of derailing it, so I did so on the Open Thread.
https://forum.arctic-sea-ice.net/index.php/topic,1884.250.html#lastPost


Title: Re: The 2017 melting season
Post by: magnamentis on March 20, 2017, 10:53:14 PM
..... unless we humans get our act together, the rest of the earths systems are going to change so much that the normal will not be as it was even 20 years ago.

i mean this serious and just adding without wanting to be negative more than what i really believe, that said, we're beyond that already. even if we could stop pollution NOW immediately, the sh....t is already hitting the fan, it's too late to avoid it while we can and should reduce the worst to the unavoidable bad which means that there is good reason to make any effort we can ( has to start on individual level, person by person changing life style, priorities and attitude ) to reduce our environmental footprints, else it could be worse than even we believe.

so to make this clear, i agree with what you're heading at, it's just important to call things by their real name and in this case the real name is that we cannot revert the process in time, not in theory and by no means in practice but we can do our best which of course we as mankind are lightyears away of doing unfortunately.
Title: Re: The 2017 melting season
Post by: dosibl on March 20, 2017, 11:42:16 PM
Thanks for the tips, plenty of things to keep an eye on.

Definitely interested in watching the Beaufort sea, comparing March 20th across the past few years shows how stark the difference is.
Title: Re: The 2017 melting season
Post by: charles_oil on March 20, 2017, 11:53:50 PM

I think those three graphs definitely qualify for a WOW ... buckle up ... response !

Title: Re: The 2017 melting season
Post by: Tigertown on March 21, 2017, 12:13:03 AM
A better look at the Laptev.
CLICK IMAGE PLEASE
(http://)
Title: Re: The 2017 melting season
Post by: Michael J on March 21, 2017, 12:26:13 AM
Before we get too deep into melting season, would some of the more seasoned posters mind giving a handful of things they will be keeping an eye on over the next few months to judge how 'good' or 'bad' the melt is going?

This will be my (and I suspect some others) first melting season so it'd be nice to know what to expect in general, as well as what to watch coming from such an extreme freezing season.

This is my fourth year and my advice is don't judge. It only takes a few weeks of the right/wrong kind of weather to turn a bad/good year into a good/bad year.

Also even the seasoned observers get surprised, over the short time I've been watching it the melt has changed. In the first year it was all melt ponds and large cracks the the ice cap seemed solid. Now (from a distance) it is more mush and can flow with the winds and currents.
Title: Re: The 2017 melting season
Post by: Cate on March 21, 2017, 12:36:36 AM
New post today from Robertscribbler: "Frailest Ever Winter Sea Ice Facing a Cruel, Cruel Summer."

https://robertscribbler.com/2017/03/20/frailest-ever-winter-sea-ice-facing-a-cruel-cruel-summer/
Title: Re: The 2017 melting season
Post by: Hyperion on March 21, 2017, 01:41:53 AM
Before we get too deep into melting season, would some of the more seasoned posters mind giving a handful of things they will be keeping an eye on over the next few months to judge how 'good' or 'bad' the melt is going?

This will be my (and I suspect some others) first melting season so it'd be nice to know what to expect in general, as well as what to watch coming from such an extreme freezing season.

My quick and off the cuff list might be as follows:
1: What real world empirical  data can we trust regarding the state of the halocline. -once the besieged lower salinity surface waters are exported and corrupted by salt enrichment from the winter there can be no winter refreeze.
2: How much water vapour is smoking in to the zone on unforeseen atmospheric circulation systemic reformations. - as it phase transitions from vapour to liquid or even more so importantly from liquid to solid it emits photons in all directions, most importantly downwards, that are precisely the frequency for the reverse transition of water molecules in the reverse homily to elevate their energy level via a melt or boil.
3: How much export transport of ice out of the basin is current and ongoing, what salt/ water ratio is part of this equation,  with implications obvious for (1)

Title: Re: The 2017 melting season
Post by: romett1 on March 21, 2017, 09:23:30 AM
Latest GFS (Climate Reanalyzer) shows following anomalies for Arctic until next Tuesday.
Although anomalies will go down next week, Kara, Laptev and ESS remain warmer than usual.
Title: Re: The 2017 melting season
Post by: Jim Williams on March 21, 2017, 12:17:39 PM
Before we get too deep into melting season, would some of the more seasoned posters mind giving a handful of things they will be keeping an eye on over the next few months to judge how 'good' or 'bad' the melt is going?

This will be my (and I suspect some others) first melting season so it'd be nice to know what to expect in general, as well as what to watch coming from such an extreme freezing season.

My quick and off the cuff list might be as follows:
1: What real world empirical  data can we trust regarding the state of the halocline. -once the besieged lower salinity surface waters are exported and corrupted by salt enrichment from the winter there can be no winter refreeze.
2: How much water vapour is smoking in to the zone on unforeseen atmospheric circulation systemic reformations. - as it phase transitions from vapour to liquid or even more so importantly from liquid to solid it emits photons in all directions, most importantly downwards, that are precisely the frequency for the reverse transition of water molecules in the reverse homily to elevate their energy level via a melt or boil.
3: How much export transport of ice out of the basin is current and ongoing, what salt/ water ratio is part of this equation,  with implications obvious for (1)
I have to agree totally with this list, and I had not considered the implications of ice export for the fresh-water lens before.

I'll be watching mostly the DMI 80N, and the reasons Hyperion gave are the reasons I'll be watching.
Title: Re: The 2017 melting season
Post by: crandles on March 21, 2017, 02:16:13 PM
New post today from Robertscribbler: "Frailest Ever Winter Sea Ice Facing a Cruel, Cruel Summer."

https://robertscribbler.com/2017/03/20/frailest-ever-winter-sea-ice-facing-a-cruel-cruel-summer/

Neven and the sea ice observers over at The Arctic Sea Ice blog produced the following graph depicting what is all-too-likely to be a 2017 in which the sea ice extent maximum just hit another consecutive annual record low:

(2015, 2016 and 2017 were three consecutive record low winter maximum years for sea ice extent in a row. Image by Deeenngee and The Arctic Sea Ice Blog.)

Neven, who is one of the world’s top sea ice analysts,

;D
Title: Re: The 2017 melting season
Post by: Neven on March 21, 2017, 02:36:33 PM
I had to laugh too.  ;)
Title: Re: The 2017 melting season
Post by: Tigertown on March 21, 2017, 03:04:58 PM
SMOS 18th-20th
CLICK IMAGE TO ACTIVATE
(http://)
Title: Re: The 2017 melting season
Post by: Ajpope85 on March 21, 2017, 03:43:59 PM
SMOS 18th-20th
CLICK IMAGE TO ACTIVATE
(http://)

Is what is going on around the north pole noise?
Title: Re: The 2017 melting season
Post by: Jim Hunt on March 21, 2017, 03:46:27 PM
I had to laugh too.  ;)

Snow White is disgusted. Blatant gender discrimination! How high is the glass ceiling in the Arctic?
Title: Re: The 2017 melting season
Post by: Gray-Wolf on March 21, 2017, 03:55:14 PM
Isn't anybody going to cheer me up?

I've been stunned, through re-freeze, by the scale of the departure from an 'old' Arctic winter and now that most of the basin is 'visible' again on Sat I am further stunned by 'the look' of the ice!

Tell me I have it all wrong and the ice is all 'good ice' and not pathetic warm stuff that shatters into teeny bits when stressed?

When I look at the peripheral areas they are awash with swirls of froth from melt and we should not be even melting yet?

Persuade me ,anybody!, that I have it all wrong and that any high melt/high export behaviours over May/June will not leave us in a lot of trouble?

Reassure me that even if the basin soaks up nearly twice the energy it did last year we will not be blighted by extreme weathers over Autumn/early winter!

Anybody?
Title: Re: The 2017 melting season
Post by: bbr2314 on March 21, 2017, 04:22:59 PM
Isn't anybody going to cheer me up?

I've been stunned, through re-freeze, by the scale of the departure from an 'old' Arctic winter and now that most of the basin is 'visible' again on Sat I am further stunned by 'the look' of the ice!

Tell me I have it all wrong and the ice is all 'good ice' and not pathetic warm stuff that shatters into teeny bits when stressed?

When I look at the peripheral areas they are awash with swirls of froth from melt and we should not be even melting yet?

Persuade me ,anybody!, that I have it all wrong and that any high melt/high export behaviours over May/June will not leave us in a lot of trouble?

Reassure me that even if the basin soaks up nearly twice the energy it did last year we will not be blighted by extreme weathers over Autumn/early winter!

Anybody?

"it was stripped, nearly to the bone, within hours"

https://en.wikipedia.org/wiki/Shooting_an_Elephant

(https://www7320.nrlssc.navy.mil/hycomARC/navo/arcticictn_nowcast_anim30d.gif)
Title: Re: The 2017 melting season
Post by: Jim Hunt on March 21, 2017, 04:41:06 PM
A better look at the Laptev

Quite so. The Suomi "Nighttime Imagery" is a useful addition to the Worldview toolkit.
Title: Re: The 2017 melting season
Post by: oren on March 21, 2017, 05:33:22 PM
The elephant is all mashed up, and it seems a significant part of the PIOMAS "blob" will cross the point of no return this coming week. On the other hand, eyeballing Hycom it seems the Beaufort will be thickening/compacting, and that peripheral extent might benefit from dispersion.
Title: Re: The 2017 melting season
Post by: Lord M Vader on March 21, 2017, 08:06:38 PM
About 4-5 days from now the Arctic basin will most likely suffer a huge damage as a very favorable pattern for sea ice transport to the Atlantic "death row" will set up and linger for several days (see attached figure showing ECMWF 12z op run for the worst moment at +168h from now). Both GFS and ECMWF agrees about this solution even if ECMWFs solution is more severe for the sea ice.

We will most likely see thick ice make an exit to the Atlantic "death zone" which should give the upcoming melting season a decent start.

Courtesy: Tropical Tidbits/Lewi Cowan

(http://www.tropicaltidbits.com/analysis/models/ecmwf/2017032112/ecmwf_z500_mslp_nhem_8.png)
Title: Re: The 2017 melting season
Post by: seaicesailor on March 21, 2017, 08:30:10 PM
Thanks LMV.
Too see the Atlantic currents break thru the ice is going to be an spectacle, a lot of thick ice already sitting on top of the Spitsbergen current for instance.
The forecast shows also high pressure system wanting to stay over Beaufort, let us see whether that realizes and especially persists, in which case it would be dangerous to Beaufort sea ice in April.
Title: Re: The 2017 melting season
Post by: Buddy on March 21, 2017, 08:31:39 PM
We will most likely see thick ice make an exit to the Atlantic "death zone" which should give the upcoming melting season a decent start.

A decent start from a record low level = bad news....... :-\
Title: Re: The 2017 melting season
Post by: Gray-Wolf on March 21, 2017, 09:12:10 PM
Thanks LMV.
Too see the Atlantic currents break thru the ice is going to be an spectacle, a lot of thick ice already sitting on top of the Spitsbergen current for instance.
The forecast shows also high pressure system wanting to stay over Beaufort, let us see whether that realizes and especially persists, in which case it would be dangerous to Beaufort sea ice in April.

I'm concerned about H.P. systems and what we saw of them as we entered into sunspot min last time around? If H.P. builds across Russia , as it did in 2010, then this could link into Beaufort ,across ESS, leaving Atlantic lows running into Barentsz/Kara setting up high export off the end of the Trans Arctic Drift and into Fram whilst Beaufort roasts?

If we are also in the market for a return of the 'Perfect Melt Storm synoptic then we are done! large areas of the basin open up to sun by the start of July??? Does not sit well in my kind of mind!!!
Title: Re: The 2017 melting season
Post by: Iain on March 21, 2017, 10:42:42 PM
<no off-topic stuff in this thread, especially when related to Donnie Tiny Hands. Take it elsewhere; N.>
Title: Re: The 2017 melting season
Post by: Tigertown on March 22, 2017, 04:24:04 AM
A couple areas that are noteworthy today.
(http://)
Title: Re: The 2017 melting season
Post by: jdallen on March 22, 2017, 07:20:33 AM
A couple areas that are noteworthy today.
(http://)
Indeed.  The Kara is just getting hammered and will continue to be for at least the next 10 days.  The Hudson starting to come apart is a little unexpected, and not at the same time.  Ice there in spite of recent cold temperatures has never had a chance to really set up and is quite a bit less solid and less thick than I've seen previously (which admittedly is only 5 years...).

Both breaking open will increase insolation uptake at a point very early in the melt season.

It implication of that from the Hudson is not that great.  Ice leaving the Kara is much more troublesome, as it will introduce heat at high latitude and eliminate ice which buttresses both the CAB and Laptev.  Admittedly the Barentsz is more important for the CAB, but it all works together, and without some integration we will see albedo reductions in the high arctic even with out melt ponds, as peripheral ice melts, and permits the main pack to disperse.
Title: Re: The 2017 melting season
Post by: jdallen on March 22, 2017, 07:38:24 AM
EOSDIS image, aqua-modis, palette squashed to 230-255K, white to green/black (hottest)

The largest concentration of thickest MYI in the arctic lies in the center of the field of view, mostly between N. Greenland and the Pole.

It is fractured to a faire-the-well, poised to get pushed into the FJL/Svalbard/Fram killing ground, as it is pounded by the strong persistent westerlies roaring around the low pressure systems spinning into the CAB from the N. Atlantic.

Not a good way to start things.  I wouldn't expect to see ice like this until at least June.

(Edit: replaced the original screen shot as it turned the > 255K regions white.  Link:
https://worldview.earthdata.nasa.gov/?p=arctic&l=MODIS_Aqua_Brightness_Temp_Band31_Day(opacity=0.44,palette=green_1,min=228.7,max=256.5,squash),Coastlines&t=2017-03-21&z=3&v=-1178165.0457067718,-1091186.6011562506,1607114.9542932282,338317.3988437494
)
Title: Re: The 2017 melting season
Post by: romett1 on March 22, 2017, 09:22:18 AM
Latest GFS (Climate Reanalyzer) shows again bit higher anomalies until next Wednesday.
Kara, Laptev and ESS warmest, but heat also extends to North Pole and Beaufort.
From Sat - Wed strong winds over Barents Sea.
Title: Re: The 2017 melting season
Post by: Sam on March 22, 2017, 09:24:15 AM
Jdallen,

This just really became apparent on the 21st.

https://go.nasa.gov/2nAl97Z

If you use the video tool and run it from the 13th to the present, it is clear that the transport of this ice to the Fram is already underway in a big way.  :o

It appears that we may see truly dramatic changes in the ice over the next week.

P.s.  I find it hard to imagine with this sort of ice movement having the Barneo ice camp happen at all this year.
Title: Re: The 2017 melting season
Post by: Neven on March 22, 2017, 09:48:58 AM
Your profile has been released, Sam.
Title: Re: The 2017 melting season
Post by: Jim Hunt on March 22, 2017, 10:22:11 AM
I find it hard to imagine with this sort of ice movement having the Barneo ice camp happen at all this year.


It seems the 'copters are grounded in Khatanga by weather at the moment:

http://forum.arctic-sea-ice.net/index.php/topic,1905.msg107203.html#msg107203 (http://forum.arctic-sea-ice.net/index.php/topic,1905.msg107203.html#msg107203)

Maybe the search for a solid floe will start tomorrow?
Title: Re: The 2017 melting season
Post by: Neven on March 22, 2017, 10:53:43 AM
Indeed.  The Kara is just getting hammered and will continue to be for at least the next 10 days.

That to me is the most noteworthy event in the Arctic right now. I've made an animation of the ice retreat south of Novaya Zemlya for the last 8 days:

(https://lh3.googleusercontent.com/zHlNH5e0kjoXlAt43WCuD386ZUFlszXd_q_OBL4lpZLVZJiAEQL0ttsGe3I2V-ZTimOodxWJ-c5vwuGg9PMHMb1LfMx2zW0E-Peqioi5oT177duWQV7rg0s35ZETne55RoDAdvMn7hYlNMUvWq5yRr6z5c9UZmc_C63gGraeQsrWk4prrzC8feBq9eJ3u7i3ace5auWmCtn8NbsSK6ZW1vmelqzqSTr6PyAFzFrObx5e6ssYFQdnQB2pP0axpLFpTxtMQtd_907DFsZdtt39wiBQCVj_XOG8fVOQ1q0MqNVAlrg7BO5i8V8r6gEzUPDTf28_Gh8ZREF-Jedc7V5_o_9vy3c7aOkLAaMrSXnEqer00Hw_UDi3sVl9QC_6MUxMkfk2_ncOdO3Id4LtxYhviEU3pI_VQInH9vjU5tGBltsTAFa9xnNRSF1M3htbca7NJ4A9gUpGLmaGwQLp1wj9mtW-5dU-GCwB4mPL4FTZDpcMedKru8JRmVzOJTbZIC92Bk6te79n05O-aS9djCC_CIXTpQWV1HxCktz7Hrej0Hov33yob-_mOZynJ0btQJ9yI2BRjzkzVyJ8_hBb7ICyPculitzi74pjtxsV7FM2Grk2V_CjpBRX=s340-no)

Given the current wind and temps forecast this is going to continue for at least another week.

And so the big question becomes: Will this freeze over again when the winds reverse?

It did back in 2011 and 2012, but this time the retreat will go further, I expect.

2011:

(http://neven1.typepad.com/.a/6a0133f03a1e37970b016302fdb454970d-pi)

2012:

(http://neven1.typepad.com/.a/6a0133f03a1e37970b016303d7f776970d-800wi)

When things closed up again, they stayed that way until mid-May. Still, this could be another unprecedented, amigos.
Title: Re: The 2017 melting season
Post by: Jim Hunt on March 22, 2017, 12:13:01 PM
Still, this could be another unprecedented, amigos.


I'd noticed that too Neven:

http://GreatWhiteCon.info/2017/03/facts-about-the-arctic-in-march-2017/#comment-220245 (http://GreatWhiteCon.info/2017/03/facts-about-the-arctic-in-march-2017/#comment-220245)

The Hamburg Uni processing pipeline seems to be gummed up at the moment, but this is how things looked yesterday:

Title: Re: The 2017 melting season
Post by: Adam Ash on March 22, 2017, 01:03:16 PM
Indeed.  The Kara is just getting hammered and will continue to be for at least the next 10 days.
That to me is the most noteworthy event in the Arctic right now. I've made an animation of the ice retreat south of Novaya Zemlya for the last 8 days:
...
When things closed up again, they stayed that way until mid-May. Still, this could be another unprecedented, amigos.

And its not just the retreat, its the loss of density of all the pack shown in the image...  wow!  Ten more days, the ice could be literally diving into summer!
Title: Re: The 2017 melting season
Post by: Juan C. García on March 22, 2017, 03:04:05 PM
Indeed.  The Kara is just getting hammered and will continue to be for at least the next 10 days.
That to me is the most noteworthy event in the Arctic right now.

I am also very concerned about the ice, north of Greenland:

The largest concentration of thickest MYI in the arctic lies in the center of the field of view, mostly between N. Greenland and the Pole.

It is fractured to a faire-the-well, poised to get pushed into the FJL/Svalbard/Fram killing ground, as it is pounded by the strong persistent westerlies roaring around the low pressure systems spinning into the CAB from the N. Atlantic.

Not a good way to start things.  I wouldn't expect to see ice like this until at least June.

Title: Re: The 2017 melting season
Post by: sondreb on March 22, 2017, 03:12:29 PM
As a follow-up to the post by jdallen, I made an animated gif of the same view (March 20-21, varied to get less clouds) for 2013-2017, 5 sec delay between images.

(Another note: Have accounts been deleted? Deleted automatically when inactive? Couldn't find my account and made a new one)
Title: Re: The 2017 melting season
Post by: Neven on March 22, 2017, 03:35:33 PM
Your new profile has been released, sondreb, so you can post freely now.
Title: Re: The 2017 melting season
Post by: Sam on March 22, 2017, 03:52:37 PM
The Russian Expedition sent two mil 8 helicopters out to begin searching for a stable flow for ice station Barneo on Sunday. They report that they reached Severnaya Zemlya from Krasnoyarsk.

https://thebarentsobserver.com/en/arctic/2017/03/russias-north-pole-camp-making (https://thebarentsobserver.com/en/arctic/2017/03/russias-north-pole-camp-making)

The video about the airdrome being open is from 2016.

https://www.facebook.com/BarneoRu (https://www.facebook.com/BarneoRu)
http://www.ag24.ru/news/206-Iz-Krasnoyarska-do-Severnogo-polyusa (http://www.ag24.ru/news/206-Iz-Krasnoyarska-do-Severnogo-polyusa)

With the tremendous fracturing and ice movement all around the pole as the ice sheet rotates, it is hard for me to imagine how they will find ice stable enough to build the ice station this year.

https://go.nasa.gov/2nBHVvU (https://go.nasa.gov/2nBHVvU)

Perhaps it is fortunate that the weather turned when it did. Two weeks later and the ice station might have been under construction as the breakup began. They might well have lost another An-74 to the ice.



Title: Re: The 2017 melting season
Post by: Rick Aster on March 22, 2017, 04:15:43 PM
The Russian Expedition sent two mil 8 helicopters out to begin searching for a stable flow for ice station Barneo on Sunday...

I think it's been mentioned a couple of times, but readers wanting to keep up with Barneo will be interested in the Barneo 2017 thread. http://forum.arctic-sea-ice.net/index.php/topic,1905.0.html (http://forum.arctic-sea-ice.net/index.php/topic,1905.0.html)
Title: Re: The 2017 melting season
Post by: seaicesailor on March 22, 2017, 04:18:44 PM
From last entry of Judah Cohen blog, this speculation I think of interest here, worth being taken into account. Interesting that he does take as valid the excess in accumulated snow (depth, not extent) in Siberia and Canada shown by the models.

Longer term, the global environment favors mild temperatures for the coming months.  The Arctic remains exceptionally warm, aided by record or near record low sea ice; land and ocean temperatures also remain near record warm temperatures.  The only boundary forcing that I can think of that may contribute to relatively cool temperatures is snow cover across the NH.  The amount of snow covering (in mass not extent) the NH is the highest observed over the past twenty years or so.  I hope to be able to tweet out this week a graph of the snow mass this winter across the NH.  A deep snowpack across Canada and especially Siberia will retard warming at least across the high latitudes of the continents that may be transported episodically to lower latitudes.

https://www.aer.com/science-research/climate-weather/arctic-oscillation (https://www.aer.com/science-research/climate-weather/arctic-oscillation)
Title: Re: The 2017 melting season
Post by: Sam on March 22, 2017, 04:32:44 PM
Rick,

Thank you.  I had not found that thread.

Like jdallen and Juan, my larger concern is the state of the ice poleward north of Greenland.  Since the 20th, in addition to the retreat from the Kara, there appears to be a general anti-clockwise rotation that is breaking up all of the ice around the pole from 85 degrees north. This is most evident on the Canadian side of the pole, but also seems to be appearing in the Russian side.

Sam
Title: Re: The 2017 melting season
Post by: bbr2314 on March 22, 2017, 06:14:24 PM
From last entry of Judah Cohen blog, this speculation I think of interest here, worth being taken into account. Interesting that he does take as valid the excess in accumulated snow (depth, not extent) in Siberia and Canada shown by the models.

Longer term, the global environment favors mild temperatures for the coming months.  The Arctic remains exceptionally warm, aided by record or near record low sea ice; land and ocean temperatures also remain near record warm temperatures.  The only boundary forcing that I can think of that may contribute to relatively cool temperatures is snow cover across the NH.  The amount of snow covering (in mass not extent) the NH is the highest observed over the past twenty years or so.  I hope to be able to tweet out this week a graph of the snow mass this winter across the NH.  A deep snowpack across Canada and especially Siberia will retard warming at least across the high latitudes of the continents that may be transported episodically to lower latitudes.

https://www.aer.com/science-research/climate-weather/arctic-oscillation (https://www.aer.com/science-research/climate-weather/arctic-oscillation)

While my previous posts re: impending ice age due to runaway NHEM snowcover may be both insane and wrong (but possibly not!), I think that if it is correct, it is making itself quite obvious already...

Consider that this winter New York City has seen over 30" of snow (slightly above normal) while having one of its warmest winters on record (I believe top 5). Not only that, but this follows the same situation last year (32", even warmer I believe).

We are now seeing concurrent warming *and* increases in snow, even down at 41N. If that is the case in the mid-latitudes, as the graphs make clear, the situation is even more dramatic further north.

Is this increase enough to counter the background warming yet? Absolutely not (and perhaps it will never be). But one has to wonder if the seemingly unprecedented increase in global snowfall is only just beginning -- will be very interesting to watch the response this summer and autumn as the sea ice will (IMO) likely hit record low numbers.
Title: Re: The 2017 melting season
Post by: DrTskoul on March 22, 2017, 06:26:41 PM
For max snowfall you need a warmish atmosphere with lots of water vapor and temperatures around freezing. Too cold and rel humidity is lower and snow flakes are too small. Around and little above zero C flakes are at their largest and depth builds quickly. A little warmer and it's rain... no I do not see that happening....a ton of snow that melts quickly....
Title: Re: The 2017 melting season
Post by: Lord M Vader on March 22, 2017, 06:45:14 PM
The very high snow cover extent is a double egged sword. If the spring is cool it will likely help to benefit the sea ice. OTOH, if the spring is going to be warm or very warm it could yield a very big river runoff with fresh water to the Arctic basin, just like it did back in 2012 if my memory is correct.
Title: Re: The 2017 melting season
Post by: Tigertown on March 22, 2017, 07:01:49 PM

Like jdallen and Juan, my larger concern is the state of the ice poleward north of Greenland.  Since the 20th, in addition to the retreat from the Kara, there appears to be a general anti-clockwise rotation that is breaking up all of the ice around the pole from 85 degrees north. This is most evident on the Canadian side of the pole, but also seems to be appearing in the Russian side.

Sam
(http://)
Title: Re: The 2017 melting season
Post by: jdallen on March 22, 2017, 07:20:28 PM

Like jdallen and Juan, my larger concern is the state of the ice poleward north of Greenland.  Since the 20th, in addition to the retreat from the Kara, there appears to be a general anti-clockwise rotation that is breaking up all of the ice around the pole from 85 degrees north. This is most evident on the Canadian side of the pole, but also seems to be appearing in the Russian side.

Sam

Welcome to the age of the "whole arctic gyre"
Title: Re: The 2017 melting season
Post by: bbr2314 on March 22, 2017, 07:24:35 PM
For max snowfall you need a warmish atmosphere with lots of water vapor and temperatures around freezing. Too cold and rel humidity is lower and snow flakes are too small. Around and little above zero C flakes are at their largest and depth builds quickly. A little warmer and it's rain... no I do not see that happening....a ton of snow that melts quickly....
IDK about that; yes that is the case for places like NYC that get 30" of snow in an average winter, but further north, even with the warming we have seen, areas 42-43N+ are almost always substantially below freezing from November through March.

Indeed, you are correct that at 0C things become perilous for frozen precipitation, but the thing is, even with the blazing reds of the anomaly maps, Siberia/Canada/the northern tier most everywhere is still very far from reaching that mark (except for Svalbard/areas adjacent to the newly-opened-Arctic Ocean, where the year-round climate has seemingly shifted towards Oceanic vs. Arctic).
Title: Re: The 2017 melting season
Post by: bbr2314 on March 22, 2017, 08:04:25 PM
Also: WRT the accuracy of the northern hemisphere snow charts, it would seem to me that the pattern shown on 3/21 would match the recent papers showing a decline in Eastern Himalayan snowfall (and plateau in central Himalayan snows) concurrent with a dramatic rise in the western portion. I would posit that this is directly related to increasingly open sea area in Kara/Barentz (due NW of the Western Himalayas/Turkey/Iran, all of which have seen collossal amounts of snow this winter), perhaps combined with very warm sea temps in the Arabian & Indian Oceans.

(https://www.ccin.ca/home/sites/default/files/snow/snow_tracker/plot_anom_sdep.png)
Title: Re: The 2017 melting season
Post by: Jim Williams on March 22, 2017, 08:44:26 PM
For max snowfall you need a warmish atmosphere with lots of water vapor and temperatures around freezing. Too cold and rel humidity is lower and snow flakes are too small. Around and little above zero C flakes are at their largest and depth builds quickly. A little warmer and it's rain... no I do not see that happening....a ton of snow that melts quickly....

Agreed.  That has been the recent history.
Title: Re: The 2017 melting season
Post by: seaicesailor on March 22, 2017, 11:33:54 PM
Anyway I remember maps with similar positive anomalies last year in Eastern Siberia and disappeared pretty abruptly. In fact a heat wave in May or June started last years ESS bite. Its really unpredictable.
Models hinting for that Beaufort high forming in five days and coupling with a strong Laptev low for two or three days. We may see some wind-driven sea ice drift clockwise in the Beaufort sea after all ( though the underlying Gyre ocean current seems dead to me, not the slightest displacement this year so far).
Title: Re: The 2017 melting season
Post by: Ice Shieldz on March 22, 2017, 11:51:14 PM
The very high snow cover extent is a double egged sword. If the spring is cool it will likely help to benefit the sea ice. OTOH, if the spring is going to be warm or very warm it could yield a very big river runoff with fresh water to the Arctic basin, just like it did back in 2012 if my memory is correct.

Make that a quadruple edged sword, since fall/winter snow will serve to both trap extra heat in the ground and keep the sea ice from growing as rapidly.  Also the extra Siberian snow cover associated with WACC supports wavier jet, disrupted vortex and associated increases in heat/moisture.  The extra snow is a positive feedback that speeds up the demise of Arctic winter power, etc.
Title: Re: The 2017 melting season
Post by: jgnfld on March 23, 2017, 12:59:35 AM
...
We are now seeing concurrent warming *and* increases in snow, even down at 41N. If that is the case in the mid-latitudes, as the graphs make clear, the situation is even more dramatic further north.

Is this increase enough to counter the background warming yet? Absolutely not (and perhaps it will never be). But one has to wonder if the seemingly unprecedented increase in global snowfall is only just beginning -- will be very interesting to watch the response this summer and autumn as the sea ice will (IMO) likely hit record low numbers.
Just to be clear, is it your contention that snow means there is cooling??? If so can you please cite the research which shows that?  I've lived in the subarctic most of my life. In my experience snow means warming, though still at or a bit below 0C.  It just doesn't snow when the temps are arctic cold and the pressure is high.
Title: Re: The 2017 melting season
Post by: bbr2314 on March 23, 2017, 02:53:12 AM
...
We are now seeing concurrent warming *and* increases in snow, even down at 41N. If that is the case in the mid-latitudes, as the graphs make clear, the situation is even more dramatic further north.

Is this increase enough to counter the background warming yet? Absolutely not (and perhaps it will never be). But one has to wonder if the seemingly unprecedented increase in global snowfall is only just beginning -- will be very interesting to watch the response this summer and autumn as the sea ice will (IMO) likely hit record low numbers.
Just to be clear, is it your contention that snow means there is cooling??? If so can you please cite the research which shows that?  I've lived in the subarctic most of my life. In my experience snow means warming, though still at or a bit below 0C.  It just doesn't snow when the temps are arctic cold and the pressure is high.
No, that is not my contention -- I am saying that the current amount of warming combined with the increasingly open Arctic Ocean results in more snowfall. Currently this results in relatively small opportunities for negative temperature anomalies (like last fall, where the +++snowfall in areas that don't normally see it so early resulted in very negative departures across much of Asia in October/November).

Eventually, if this feedback continues to amplify, I suspect it could lead to much more dramatic cooling by way of albedo effect. But we are most definitely not yet at that point and it may not even exist (though I suspect it does).
Title: Re: The 2017 melting season
Post by: Tigertown on March 23, 2017, 03:19:34 AM
...
We are now seeing concurrent warming *and* increases in snow, even down at 41N. If that is the case in the mid-latitudes, as the graphs make clear, the situation is even more dramatic further north.

Is this increase enough to counter the background warming yet? Absolutely not (and perhaps it will never be). But one has to wonder if the seemingly unprecedented increase in global snowfall is only just beginning -- will be very interesting to watch the response this summer and autumn as the sea ice will (IMO) likely hit record low numbers.
Just to be clear, is it your contention that snow means there is cooling??? If so can you please cite the research which shows that?  I've lived in the subarctic most of my life. In my experience snow means warming, though still at or a bit below 0C.  It just doesn't snow when the temps are arctic cold and the pressure is high.

No, that is not my contention -- I am saying that the current amount of warming combined with the increasingly open Arctic Ocean results in more snowfall. Currently this results in relatively small opportunities for negative temperature anomalies (like last fall, where the +++snowfall in areas that don't normally see it so early resulted in very negative departures across much of Asia in October/November).

Eventually, if this feedback continues to amplify, I suspect it could lead to much more dramatic cooling by way of albedo effect. But we are most definitely not yet at that point and it may not even exist (though I suspect it does).

I wanted to reply to this, but so as not to derail this thread,
http://forum.arctic-sea-ice.net/index.php/topic,1932.0.html
Title: Re: The 2017 melting season
Post by: Lord M Vader on March 23, 2017, 07:25:54 AM
Crossposting from IJIS-thread:

NSIDC has called the min max now which occurred by March 7: http://nsidc.org/arcticseaicenews/2017/03/arctic-sea-ice-maximum-at-record-low/ (http://nsidc.org/arcticseaicenews/2017/03/arctic-sea-ice-maximum-at-record-low/)
Title: Re: The 2017 melting season
Post by: romett1 on March 23, 2017, 10:08:31 AM
Latest GFS (Climate Reanalyzer) now shows larger anomalies until next Thursday.
Also Kara Sea goes windy starting Saturday, meaning no chance of refreeze there in near future.
Kara, Laptev and ESS as usual warmest, also Beaufort and North Pole warmer than usual.
Title: Re: The 2017 melting season
Post by: Adam Ash on March 23, 2017, 12:35:39 PM
On the IJIS thread, JDAllan mentioned the expected formation of melt ponds on the ice around June. But given the severely fragmented nature of the ice pack this season what are the chances of melt ponds of any size forming? 

Instead, will not a more fractured pack offer significantly more 'side' to low angle insolation than the comparatively homogeneous / continuous ice pack of old?  That flow side will have high albedo but that won't help, as it will simply reflect a fair share of incident radiation downwards, into the surrounding water and onto other 'sides' nearby where the energy received will simply chew away at the sides of each floe.   
Title: Re: The 2017 melting season
Post by: gerontocrat on March 23, 2017, 12:41:13 PM
Jaxa sea-ice drift graph shows considerable sea-ice drift south out of Baffin Bay. Significant?
Weather-forecast.com indicates probable massive ESE movement of ice into open water Monday Tuesday Wednesday next week. This observer is not finding anything to indicate any reason for melting to slow down yet.
Title: Re: The 2017 melting season
Post by: DoomInTheUK on March 23, 2017, 12:42:54 PM
Yes the pack is fragmented, but the individual pieces are still quite large. Don't forget a flow that is only 1 pixel will still be many kilometres across. Melt ponds will be on the 10's to possibly 100's meters scale. There's several order of magnitude there.

Not until the flows break up to around the melt pond scale will side melt make a major difference.
The pack may be shattered, but it's still almost all top and bottom melt.
Title: Re: The 2017 melting season
Post by: jai mitchell on March 23, 2017, 08:35:32 PM
is there a metric for daily or weekly sea ice mobility anomaly?  this would be very useful when the Arctic turns into a single gyre.
Title: Re: The 2017 melting season
Post by: Pmt111500 on March 23, 2017, 09:33:19 PM
is there a metric for daily or weekly sea ice mobility anomaly?  this would be very useful when the Arctic turns into a single gyre.
Nevö höörd nevöevö... never heard of such a thing. People still believe thaere's weather.
Title: Re: The 2017 melting season
Post by: slow wing on March 24, 2017, 12:50:07 AM
"...the Arctic turns into a single gyre"?

 There hasn't even been a gyre lately. Instead the ice in the Arctic Basin has been blown from the Russian side and compressed against the Canadian side, with some leaking out towards the Atlantic...

(https://www7320.nrlssc.navy.mil/hycomARC/navo/arcticictn_nowcast_anim30d.gif)


  The good news is that the compression has helped to heal the Beaufort Sea back to around a 2 metre thickness.

   And if the pattern ends soon then there is still well over a month left of weather cold enough to somewhat heal the tears on the Russian side.

   But what if the tear-and-compression continues well into April or May? Will large stretches of water remain open on the Russian side, efficiently absorbing the peak insolation around the Summer solstice?

  A broader question is why so much compression? Is there enough thin and weak ice this year in the Arctic Basin that any wind pressure from the Russian side will always result in movement and compression? And is this movement replacing the Beaufort gyre of seasons past, with the ice now compressing rather than transferring the force for rotation?

   If so, does this mean that maximum Arctic sea ice volume for the year has descended this season to a transition value, or even a tipping point, where the ice will continue to tear-and-compress from the Russian side heading into the Summer melt season, with the Russian side therefore opening up anomalously early?

   Or, instead, will the movement damp down within a few weeks and those consequences won't come to pass this year?

   Either way, the plot twists and turns of the melt season are going to provide us with riveting viewing.
Title: Re: The 2017 melting season
Post by: epiphyte on March 24, 2017, 03:00:48 AM
(I tried to post this earlier, but it didn't work. Scaled it down and trying again...)

Pan-Arctic Gyre firing up?
Title: Re: The 2017 melting season
Post by: cesium62 on March 24, 2017, 05:32:59 AM
Before we get too deep into melting season, would some of the more seasoned posters mind giving a handful of things they will be keeping an eye on over the next few months to judge how 'good' or 'bad' the melt is going?

This will be my (and I suspect some others) first melting season so it'd be nice to know what to expect in general, as well as what to watch coming from such an extreme freezing season.

I always enjoy "watching" the spring flood of the MacKenzie River in early May.  In recent years, it has produced a burst of early warmth into the Beaufort.  About the same time, we may also start to see large forest fires in Canada and Siberia producing a burst of speculation about their effects on the climate and vice versa.

As others have mentioned, watching the Beaufort throughout the season is interesting.  In 2015, there was a large patch of thick ice that lingered and kept ice extent and area high there.  But that patch was rotating clockwise.  So in 2016, there seemed to be relatively thick ice in the ESS and Laptev that kept those seas from melting out until late in the season.  So I'll be watching those seas to see if they seem to be melting out earlier this year.

Next I'm fascinated by the break up of the fast ice along the northern edge of the Canadian Archipelago.  Winds from Russia across the pole tend to pile up thick ice there during the winter, and then in summer winds and currents may carry the ice west to the warm Beaufort or east through the Fram strait, leaving impressive cracks along the shore.  And last year there were many good images of the ice being pushed south through the straits in the archipelago.

Climate Reanalyzer is a favorite tool for watching remnants of Pacific Typhoons blow through the Bering Strait and rile up the Chukchi and Beaufort Seas.  Also the regular series of storms that blow up through the North Sea and pull ice through the Fram Strait.  People get very excited when a strong low pressure system lingers in the Arctic Ocean.  A strong storm in 2012 and another last year seem to have been quite effective at dispersing ice to the south and generally cracking the ice and pushing sea water on top of the ice.

And in late August and early September, you'll watch the progress of boats through the Northwest and Northeast passages.  You may end up reading some history of some of the early multi-year attempts at navigating the Northwest passage.

More than just the weather, there's a lot of geography, history, physics, economics and geopolitics going on as well.  And talking about the weather is kind of a natural lead in to some of these other subjects.
Title: Re: The 2017 melting season
Post by: romett1 on March 24, 2017, 09:10:45 AM
Latest GFS (Climate Reanalyzer) anomalies until next Friday.
"Heatwave" stays over Kara, Laptev and ESS, also Beaufort and Northern Canada warmer than usual.
Title: Re: The 2017 melting season
Post by: Glenn Tamblyn on March 24, 2017, 11:17:08 AM
If Hycom is right, there is a very big section of ice that looks like it is leaving Baffin Bay.

https://www7320.nrlssc.navy.mil/hycomARC/navo/arcticictn_nowcast_anim30d.gif
Title: Re: The 2017 melting season
Post by: DrTskoul on March 24, 2017, 01:13:27 PM
If Hycom is right, there is a very big section of ice that looks like it is leaving Baffin Bay.

https://www7320.nrlssc.navy.mil/hycomARC/navo/arcticictn_nowcast_anim30d.gif

And Fram...
Title: Re: The 2017 melting season
Post by: Cate on March 24, 2017, 01:39:48 PM
Surface ice in Nares is moving through. I don't know how to animate---toggle the past couple of clear days to watch it. I'm sure someone here can work out the speed. ;)

Notice that the heel, toe, and sole of the bigfoot boot "arch" at the Lincoln Sea end have frozen over again, for the time being.

http://www.arctic.io/explorer/4Xa5A/2017-03-23/7-N79.9726-W66.63132 (http://www.arctic.io/explorer/4Xa5A/2017-03-23/7-N79.9726-W66.63132)
Title: Re: The 2017 melting season
Post by: Tigertown on March 24, 2017, 02:21:25 PM
I believe it to be a good possibility that the  Beaufort ice might be the only ice to offer any resistance to disintegration and melt this year. Everything else is ready to go already.
(http://)
Title: Re: The 2017 melting season
Post by: seaicesailor on March 24, 2017, 02:28:31 PM
Three animations taken from one of Worldview's sea ice concentration layers (AMSR2 12 km resolution), of the last thirteen days.
First one shows the retreat of the ice at Kara sea.
Second one shows the dispersion of the ice over Fram, Svalbard and Barents in general. In the last two frames, some retreat (or rather melting?) of the ice  near Svalbard and Fram can be observed,
The last one shows an interesting feature forming in Bering sea ice edge during the last few days, its formation not following the general drift of the ice at Bering sea. This is a wedge-like intrusion of ocean that is trying to reach the Bering Strait, more aligned with the Asian coast. Hycom shows ocean flow in that location and direction precisely.
Title: Re: The 2017 melting season
Post by: Shared Humanity on March 24, 2017, 02:28:49 PM
Surface ice in Nares is moving through. I don't know how to animate---toggle the past couple of clear days to watch it. I'm sure someone here can work out the speed. ;)

Notice that the heel, toe, and sole of the bigfoot boot "arch" at the Lincoln Sea end have frozen over again, for the time being.

[url]http://www.arctic.io/explorer/4Xa5A/2017-03-23/7-N79.9726-W66.63132[/url] ([url]http://www.arctic.io/explorer/4Xa5A/2017-03-23/7-N79.9726-W66.63132[/url])


Is it normal for that much of the Northwest passage to have such thin ice? With that large crack, it almost looks as if it is open for business.
Title: Re: The 2017 melting season
Post by: Hyperion on March 24, 2017, 02:32:06 PM
"...the Arctic turns into a single gyre"?

 There hasn't even been a gyre lately. Instead the ice in the Arctic Basin has been blown from the Russian side and compressed against the Canadian side, with some leaking out towards the Atlantic...

  The good news is that the compression has helped to heal the Beaufort Sea back to around a 2 metre thickness.

   But what if the tear-and-compression continues well into April or May? Will large stretches of water remain open on the Russian side, efficiently absorbing the peak insolation around the Summer solstice?

  A broader question is why so much compression? Is there enough thin and weak ice this year in the Arctic Basin that any wind pressure from the Russian side will always result in movement and compression? And is this movement replacing the Beaufort gyre of seasons past, with the ice now compressing rather than transferring the force for rotation?

   If so, does this mean that maximum Arctic sea ice volume for the year has descended this season to a transition value, or even a tipping point, where the ice will continue to tear-and-compress from the Russian side heading into the Summer melt season, with the Russian side therefore opening up anomalously early?

   Or, instead, will the movement damp down within a few weeks and those consequences won't come to pass this year?

   Either way, the plot twists and turns of the melt season are going to provide us with riveting viewing.

This looks a dangerous pattern indeed. If the anticlockwise forcing from low pressure systems continues then the chances of hot gulfstream water sweeping right around the top of europe onto the ESAS this summer are multiplied. This would effectively multiply the killing front where ice is being gobbled and surface low salinity surface waters are mixed away that has thus far been extending its grasp past Svalbard but blocked in recent years by FJL. If it gets well in place and a "pan Arctic CCW Gyre" sets up we could even see Pacific waters pumping in through Bering straight in Autumn to extend the Halocline killing front into a full Arctic Circle Whirlpool. ???
Title: Re: The 2017 melting season
Post by: Shared Humanity on March 24, 2017, 02:33:17 PM
I believe it to be a good possibility that the  Beaufort ice might be the only ice to offer any resistance to disintegration and melt this year. Everything else is ready to go already.
(http://)

If we are depending on the Beaufort to be the strong ice for the upcoming melt season, we are pretty well screwed.
Title: Re: The 2017 melting season
Post by: Hyperion on March 24, 2017, 02:45:58 PM
Nice Work SIS, you posted while I was typing,  :o

 
This is a wedge-like intrusion of ocean that is trying to reach the Bering Strait,

Looks like this surge is pumping a big flush out of Bering in that third Animation.
I've often wondered if there is a periodic resonance effect in the Bering in/out flows. If storm surges in from the atlantic side match the tidal resonance of the Arctic basin then it could make Bering look pretty interesting.  ::)
Title: Re: The 2017 melting season
Post by: Buddy on March 24, 2017, 03:05:12 PM
<snip, off-topic and too much caps lock (with colour no less); N.>
Title: Re: The 2017 melting season
Post by: romett1 on March 24, 2017, 03:29:13 PM
I believe it to be a good possibility that the  Beaufort ice might be the only ice to offer any resistance to disintegration and melt this year. Everything else is ready to go already.
(http://)

And we have drift forecast like this for Monday. Tuesday is pretty much the same or even worse.
Image: https://www7320.nrlssc.navy.mil/hycomARC/arctic.html
Title: Re: The 2017 melting season
Post by: Archimid on March 24, 2017, 03:55:20 PM
seaicesailor thanks. Freaking awesome animations.


If we are depending on the Beaufort to be the strong ice for the upcoming melt season, we are pretty well screwed.

If you completely ignore the lack of multiyear ice, the Beaufort looks great compared to the rest of the Arctic.
Title: Re: The 2017 melting season
Post by: Hyperion on March 24, 2017, 04:57:18 PM
Meanwhile the circulations of the less visible stuff above at this point below.
850hpa ~1.2km , 500hpa ~6km , 70hpa ~18km , 10hpa ~30km

There appears to be now a hole right through the roof of the dawn.
The counterclockwise rotations are stacked from  sea level up to 30km over the Arctic lows. And even higher I suspect. Notice the temperature is at its lowest in the 30km altitude where I have marked the green circle at 70 and 10hpa altitudes. The stratosphere starts where the temperature is lowest and rises with altitude from there. This area above the Kara and Severny Island looks like it has the updrafts from the resident lows starting to shear away, but likely still rising at 30km up. Producing this cold spot due to expansion of the rising air. The 10hpa world looks completely different to a month or two ago. Then the coldest place was above the equator, and the warmest the poles. Now the opposite. Almost anyway, the warmest spot is where I've marked with the red squiggle on the 10hpa pic above the nth Pacific. A toasty -37C ! There appears to be a third stratospheric polar Vortex establishing at this point. Descending air from even higher up? There is a pretty warm big and deep low directly below it but in the 12-18 km altitude range at that location there's a very big jetflow sprawling out into the warmest region in the 12-18km atmosphere. Over CAA and Greenland.

Very stable and unbending rivers air below aligning with the big 3-18 km altitude 30 -70 degree nth or sth meandering jets that have established. Like the Southerly blast coming up the Atlantic from off Americas east coast ound 30deg nth thats been established for  days through the whole nth sea.
We had one like that 2 weeks ago in NZ. The easterly Trades just bent and came straight down off fiji 2500km nth of here. And met a river coming 3000km from the SSW straight up off Antarctica. No "weather systems" circulating, but A 100yr flood every night for 4 days.  And gale force winds without a cyclonic driver. :o
Title: Re: The 2017 melting season
Post by: Rick Aster on March 24, 2017, 05:28:36 PM
When I look at thickness maps and satellite images of Beaufort and Chukchi seas, the ice looks smoother than I can remember ever seeing anywhere on the ocean, almost like a bigger version of lake ice. I'm not sure that impression is valid because of issues of scale. Smooth level ice is smooth on a 10-meter scale and I'm looking at more like a 10-kilometer scale. Also, the appearance of smooth ice could just reflect the new absence of multi-year ice and perhaps less vigorous cracking during the winter. With that caveat, if the ice there actually is as smooth as it appears, that could mean early melt ponds and early melting.
Title: Re: The 2017 melting season
Post by: jdallen on March 24, 2017, 07:31:52 PM
I believe it to be a good possibility that the  Beaufort ice might be the only ice to offer any resistance to disintegration and melt this year. Everything else is ready to go already.
(http://)

If we are depending on the Beaufort to be the strong ice for the upcoming melt season, we are pretty well screwed.
The Beaufort isn't thick enough.  Most of the ice there is under 2M.
Title: Re: The 2017 melting season
Post by: Jim Hunt on March 24, 2017, 10:32:47 PM
An open access paper from the Norwegian young sea ICE (N-ICE2015) expedition:

"Turbulent heat and momentum fluxes in the upper ocean under Arctic sea ice (http://onlinelibrary.wiley.com/doi/10.1002/2016JC012283/full)"

Oceanic heat flux is weakly positive in winter over the Nansen Basin during quiescent conditions, increasing by an order of magnitude during storm events. An event of local upwelling and mixing in the winter-time Nansen basin highlights the importance of individual events. Spring-time drift is confined to the Yermak Plateau and its slopes, where vertical mixing is enhanced. Wind events cause an approximate doubling of oceanic heat fluxes compared to calm periods. In June, melting conditions near the ice edge lead to heat fluxes of O(100 W m−2). The combination of wind forcing with shallow Atlantic Water layer and proximity to open waters leads to maximum heat fluxes reaching 367 W m−2, concurrent with rapid melting.
Title: Re: The 2017 melting season
Post by: Cate on March 24, 2017, 10:34:22 PM
Surface ice in Nares is moving through. I don't know how to animate---toggle the past couple of clear days to watch it. I'm sure someone here can work out the speed. ;)

Notice that the heel, toe, and sole of the bigfoot boot "arch" at the Lincoln Sea end have frozen over again, for the time being.

[url]http://www.arctic.io/explorer/4Xa5A/2017-03-23/7-N79.9726-W66.63132[/url] ([url]http://www.arctic.io/explorer/4Xa5A/2017-03-23/7-N79.9726-W66.63132[/url])


Is it normal for that much of the Northwest passage to have such thin ice? With that large crack, it almost looks as if it is open for business.


I was told that Nares usually opens in July. If you compare this same period from previous years, you can see how different the whole strait looks this year. The famous arch is key---will it hold or not? And will other arches be able to form with the ice in that state?
Title: Re: The 2017 melting season
Post by: dosibl on March 24, 2017, 10:52:14 PM
I think a fair amount of ice north of the Nares has been busy sliding towards the Fram instead of pressing on the arch, a trend which looks set to continue.
Title: Re: The 2017 melting season
Post by: JimboOmega on March 24, 2017, 11:08:40 PM
I believe it to be a good possibility that the  Beaufort ice might be the only ice to offer any resistance to disintegration and melt this year. Everything else is ready to go already.
(http://)

And we have drift forecast like this for Monday. Tuesday is pretty much the same or even worse.
Image: https://www7320.nrlssc.navy.mil/hycomARC/arctic.html

How can we have drift like this and not have large Polynya open up along the Kara Sea coast? It's been continuously warm-ish there (per cci-reanalyzer) and the 30cm/sec is 25km/day - more than enough to be visible on satellites.
Title: Re: The 2017 melting season
Post by: magnamentis on March 24, 2017, 11:23:19 PM
I believe it to be a good possibility that the  Beaufort ice might be the only ice to offer any resistance to disintegration and melt this year. Everything else is ready to go already.
(http://)

first time since long that i don't share your thoughts, that's a "dream" IMO, nothing has healed and once spring set on there will no resistance. further i don't believe in any homogenous 2m ice in the beaufort, if at all it's compresse ice sticking up or overlapping at times. i cannot imagine any scenario that exactly beaufort wouldn't melt this year, not that all the MYI is gone elsewhere or for good.

each year in this time when nothing big happens there is are a lot of ideas popping up that never hold a few weeks later. the greyhounds are in the startbox and can't wait to be released LOL
Title: Re: The 2017 melting season
Post by: Tigertown on March 24, 2017, 11:44:34 PM
I wasn't really saying that the Beaufort ice is that great compared to what it should be, only by comparison to the rest.
Title: Re: The 2017 melting season
Post by: VeliAlbertKallio on March 25, 2017, 02:19:45 AM
According to this map, the transportation of sea ice through Nares is just a small part of a much larger picture in that region. If this graph is correct, the entire sea ice cover of the Baffin Bay has started to move en masse to the Atlantic Ocean leaving behind either tiny ice veneer or open water. If so, it is no surprise that ice then can move easily out of the Kennedy Canal and the Nares Strait to the Northern Baffin Bay which is opening as ice there is also moving out. These are very large areas, indeed, to be lost barely after the spring equinox has occurred. Anyone comments how early we are with ice loss in the Baffin Bay? A friend from Nuuk (capital of Greenland) yesterday wondered from where they are getting those huge snowstorms as there are nearly 2-metre snowpile on roadsides. Best to view in scale 300% or 400% on your Internet browsers: https://www7320.nrlssc.navy.mil/hycomARC/navo/arcticictn/nowcast/ictn2017032318_2017032100_046_arcticictn.001.gif
Title: Re: The 2017 melting season
Post by: Tigertown on March 25, 2017, 02:46:57 AM
Yes, Baffin ice is really moving along.
(http://)
Title: Re: The 2017 melting season
Post by: Andreas T on March 25, 2017, 09:02:24 AM
I find the passive microwave (AMSR2) brightness temperature layer on worldview good for seeing movement on larger scales. As I have pointed out before, the colour scale (which fluctuates a lot) is not telling us much or is just too complex to interpret but it shows up recognizeable features which let you track the ice through cloudy weather.
https://go.nasa.gov/2ofX4zZ (https://go.nasa.gov/2ofX4zZ)
 
Title: Re: The 2017 melting season
Post by: romett1 on March 25, 2017, 09:15:39 AM
Latest GFS (Climate Reanalyzer) anomalies until next Saturday.
"Heatwave" extends into April over Kara, Laptev, ESS and towards North Pole.
Kara Sea is interesting to watch - wind speed 13 - 16 m/s over open water today and tomorrow.
Title: Re: The 2017 melting season
Post by: romett1 on March 25, 2017, 11:03:32 AM
Drift north of Greenland and Lincoln Sea today. I used Worldview, Brightness Temperature (Band 31-Night).
Title: The Buoys Are Back in Town
Post by: Jim Hunt on March 25, 2017, 11:30:57 AM
The buoys are back in town. Or in the Beaufort Sea actually:

http://GreatWhiteCon.info/resources/ice-mass-balance-buoys/winter-201617-imb-buoys/#2017A (http://GreatWhiteCon.info/resources/ice-mass-balance-buoys/winter-201617-imb-buoys/#2017A)

Conditions at Deployment (3/9/2017):

Snow Depth: 0 cm
Ice Thickness: 85 cm

Current Buoy Data (03/23/2017):

Pos: 72.82 N, 146.61 W
Air Temp: -24.66 C
Air Pres: 1012.43 mb
Snow depth : 10 cm
Ice thickness : 93 cm

Since Deployment (03/09/2017):

Snow surface accumulation: 10 cm
Ice bottom growth : 8 cm

See also: http://psc.apl.washington.edu/UpTempO/Data.php (http://psc.apl.washington.edu/UpTempO/Data.php)
Title: Re: The 2017 melting season
Post by: pauldry600 on March 25, 2017, 11:33:52 AM
I find it all rather alarming that Siberia seems to be consistently warmer than normal. Also when looking at uni bremen there are blue patches appearing everywhere.

Ill be very impressed if there is anything more than the lowest on record this year.

the odds must be 100/1 at least.
Title: Re: The Buoys Are Back in Town
Post by: Neven on March 25, 2017, 12:44:10 PM
Snow surface accumulation: 10 cm
Ice bottom growth : 8 cm

Wow, a whole 8 cm of bottom growth. So much for resistance to disintegration.  ;)
Title: Re: The 2017 melting season
Post by: Shared Humanity on March 25, 2017, 01:18:27 PM
Surface ice in Nares is moving through. I don't know how to animate---toggle the past couple of clear days to watch it. I'm sure someone here can work out the speed. ;)

Notice that the heel, toe, and sole of the bigfoot boot "arch" at the Lincoln Sea end have frozen over again, for the time being.

[url]http://www.arctic.io/explorer/4Xa5A/2017-03-23/7-N79.9726-W66.63132[/url] ([url]http://www.arctic.io/explorer/4Xa5A/2017-03-23/7-N79.9726-W66.63132[/url])


Is it normal for that much of the Northwest passage to have such thin ice? With that large crack, it almost looks as if it is open for business.


I was told that Nares usually opens in July. If you compare this same period from previous years, you can see how different the whole strait looks this year. The famous arch is key---will it hold or not? And will other arches be able to form with the ice in that state?


I'm not talking about Nares Strait. I'm shocked by the condition of the Northwest passage that you can see on that image.
Title: Re: The 2017 melting season
Post by: seaicesailor on March 25, 2017, 01:34:28 PM
Thanks for the info about bouy Jim.
Strange location to place that buoy, being short of funding they risk to gather like .... four months of data.
Who knows, last year Laptev sea ice, a usual "goner", did not completely melt being less than 2m (and 1m much of it) FYI. It was sealed, was cloudy and cold, it is the closest example I can come up with of the importance of (absence of) albedo feedback.
I guess this is what makes the 60% of that paper :P
Title: Re: The 2017 melting season
Post by: Iain on March 25, 2017, 01:39:29 PM
Visual confirmation the ice is moving along the full length of Nares strait and Robeson channel, however the grain size of the ice in the CAB is still too large to enter.

Meanwhile Parry channel, a conduit for ice getting through the CAA to enter Baffin bay, is still blocked between Somerset and Devon islands by an arch of ice. In 2016 it didn't break until 2nd of July. One to watch.
Title: Re: The 2017 melting season
Post by: PSJ on March 25, 2017, 03:10:21 PM
Does anyone know where to find HYCOM/CICE forecasts after March 21? It seems the usual page has not updated for some days.

https://www7320.nrlssc.navy.mil/hycomARC/arctic.html
Title: Re: The Buoys Are Back in Town/ The 2017 melting season
Post by: Tigertown on March 25, 2017, 03:15:36 PM
Snow surface accumulation: 10 cm
Ice bottom growth : 8 cm

Wow, a whole 8 cm of bottom growth. So much for resistance to disintegration.  ;)
Not only that, look at the overall thickness: 93cm....
If the ice there is that much less thick than it is supposed to be, what about the rest? I think their calibration of sat. data got threw off.
Title: Re: The 2017 melting season
Post by: iceman on March 25, 2017, 04:15:43 PM
When I look at thickness maps and satellite images of Beaufort and Chukchi seas, the ice looks smoother than I can remember ever seeing anywhere on the ocean, almost like a bigger version of lake ice. I'm not sure that impression is valid because of issues of scale. Smooth level ice is smooth on a 10-meter scale and I'm looking at more like a 10-kilometer scale. Also, the appearance of smooth ice could just reflect the new absence of multi-year ice and perhaps less vigorous cracking during the winter. With that caveat, if the ice there actually is as smooth as it appears, that could mean early melt ponds and early melting.

Indeed, even if the impression of smoothness is exaggerated, the preponderance of first-year ice means the Beaufort is extremely vulnerable to melt ponding this year.  Less fracturing than usual could result in the melt ponds persisting longer before draining.  That might be even more damaging than the early open water in Kara, though perhaps less so than above-average Fram Strait export.
Title: Re: The 2017 melting season
Post by: jai mitchell on March 25, 2017, 10:11:35 PM
Still looks like a new minimum this year.
Title: Re: The 2017 melting season
Post by: Jim Hunt on March 26, 2017, 12:01:46 AM
Does anyone know where to find HYCOM/CICE forecasts after March 21?

It seems to be up to March 24th now.
Title: pinning the tail on the donkey
Post by: Hyperion on March 26, 2017, 01:15:59 AM
Its pretty obvious that on the battlefield direct observations would benefit our understanding and eliminate a lot of uncertainty in the situation that satellite and models are creating.

Introducing the Maui Dolphin / Emperor Penguin data acquisition system. A little something I prepared earlier as a cheap and easy to manufacture and deploy ROV that can travel at up to 30kph and to ~150m depths with long term independent of pickup and maintenance capability due to solar and wave energy power generation. And surf riding high speed transit capability.
Dimensions as per namesakes.
 Estimated cost under $2000, sensors extra.
Anyone want to crowd fund some? Lets start a thread. We can make extra money by hiring them out to Webpilots in their sparetime. Moderator riding shotgun of course.  8)
Title: Re: The 2017 melting season
Post by: slow wing on March 26, 2017, 03:09:27 AM
Terrific, Hyperion!

Yes, start a thread please.

The greatest of respect to the many dedicated scientists, technicians etc. who are already providing the experimental information we rely on to understand the state of the Arctic.

Having said that, it's a disgrace that we don't have more coverage; a disgrace that we need inadequately calibrated models for the currents, water temperatures and salinities, etc - as well as information on the ice and snow state and thickness.

   Smart probes for the Arctic are difficult to fund even while smart bombs are streaming off the assembly lines.

   More broadly than your particular solution, it makes a lot of sense to have a thread on the future experimental program for monitoring the Arctic.

   Better in"Policy and solutions" or in "Science"?

   I had a look previously and couldn't find an existing thread. (Did I just miss it?)

   So there were a series of posts in the "What the Buoys are telling" thread kicking off with this one from me (http://forum.arctic-sea-ice.net/index.php/topic,327.msg90616.html#msg90616) and then with those more knowledgeable and experienced posting valuable content.

Maybe all that can be moved to a new dedicated thread for e.g. "Existing and proposed experimental apparatus and programs for the Arctic" and add your stuff and other proposed solutions?
Title: Re: The 2017 melting season
Post by: VeliAlbertKallio on March 26, 2017, 03:34:41 AM
Yes, Baffin ice is really moving along.
(http://)
Thanks Tigertown, for validating my interpretation of US Navy map.
Title: Re: The 2017 melting season
Post by: romett1 on March 26, 2017, 09:20:59 AM
Latest GFS (Climate Reanalyzer) is now forecasting bit higher anomalies until next Sunday.
"Heatwave" stays over Kara, Laptev, ESS and is heading towards North Pole later.
Title: Re: The 2017 melting season
Post by: dosibl on March 26, 2017, 05:02:31 PM
Looking at the DMI 80n graphs temps consistently start rising around day 100, whats the primary driver behind this, increase in solar energy?
Title: Re: The 2017 melting season
Post by: Tigertown on March 26, 2017, 05:10:01 PM
Looking at the DMI 80n graphs temps consistently start rising around day 100, whats the primary driver behind this, increase in solar energy?
I would think so, especially due to the angle of incidence of the solar energy, by that time of year.
Title: Re: The 2017 melting season
Post by: Tor Bejnar on March 26, 2017, 08:15:02 PM
We've been told that DMI's 80N temperature is north-pole weighted, so the NP insolation after March 20th affects the reported temperature disproportionately.
Title: Re: The 2017 melting season
Post by: seaicesailor on March 27, 2017, 12:45:25 AM
Tropicaltidbits has a nice visualization of NOAA long-range CFS model and that is always interesting, even when the skill of this model in the Arctic is been challenged in the past and we must take the predictions with a grain of salt.
These are the weekly ensemble average of a large number of runs, of pressure and temperature.
Focusing only on the persistent features, the MSLP shows that the large low pressure anomaly finally gives way to a more usual pattern in April with a high in Beaufort and a normal flow south from the Eurasian continent toward Fram thru the pole.
This translates on temperatures that are going to be anomalously high in all Siberia and all Eurasian Arctic Coast. Anomalously persistent warmth in most of Canada too, coincidentally or not. A lot of snow in both continents might start suffer decimation.
Coldness persists on Nansen basin and Greenland sea, which is associated with the northerlies that unfortunately for the MYI will keep moving it inch by inch toward the Atlantic.
Only good news for the Bering sea.
What will happen with the Beaufort sea persistent high. Repeat of '15 and '16 ?
In general not good for the Arctic but that news as usual. All of this may well be crap (1008 hours of forecast!) but it is always enjoyable to speculate some especially when more crucial moments for the menting season is about to start.
Time will tell
Title: Re: The 2017 melting season
Post by: Tigertown on March 27, 2017, 12:54:57 AM
These cracks or shears or whatever are spreading and getting worse. They have no respect for the NP region either. Only the the thick, robust, durable, mighty, 93 cm ice in the Beaufort stands a chance against these. ;)
(http://)
Title: Roundhouse punches from the ApocalyptoKraken
Post by: Hyperion on March 27, 2017, 04:51:50 AM
These Total Precipitable water maps look like theres seven water Giants wading Around the equator swinging tentacled fists under the cover of the jetsteam. In Nth and Southern Hemispheres each, three in the pacific, two per Atlantic and Indian Oceans. Every time the God Coriolis tries to deflect them, the following Kraken punches it back on course for the poles. The circulation has gone Feral! (or should that be Ferral?). Back flows seem to be at altitude. And Hadley seems history.

Quickstab at what this setup might mean numerically. Peer review and alternative approaches most welcome:
 ;)

1,680,000,000,000,000J
18.748 kg/sqm
200km x 50kmph (ballpark flow estimate) x 24hr = 240 000 sqkm = 240 000 000 000 sqm
240 000 000 000 sqm x 19 kg x 4200J = 19,152,000,000,000,000 Joules per day
=19.52 petajoules per day
Quote wikipedia:
"The petajoule (PJ) is equal to one quadrillion (10^15) joules. 210 PJ is equivalent to about 50 megatons of TNT. This is the amount of energy released by the Tsar Bomba, the largest man-made nuclear explosion ever."
"The gigajoule (GJ) is equal to one billion (10^9) joules. 6 GJ is about the amount of potential chemical energy in 160 L (approximately one US standard barrel) of oil, when combusted."
So about ten days of ApocalyptoKraken suckerpunches = 1 Tsar Bomba = 35 million Barrels of oil burned.
North pole at summer solstice gets 12.64 kWhrs per sqm. = 12.64 x 60mx 60s kJ / sqm = 45,504,000 J per sqm per day = 45 504 000 000 000J per sqkm per day.
19 152 000 000 000 000 / 45 504 000 000 000 = 420 sqkm of full midsummer insolation. About 4200sqkm of 10% absorbed as per bright white ice.
If we were to anticipate that in a few months time there might be twice as much water vapour per sqm incoming and 4000 km front of it crossing for flux calculation purposes, then it would be 80x this. So simular to 336 000 sqkm of normal midsummer insolation.
 (Neglecting other energy transported in the humid air of course. This probably of a far larger magnitude. Anyone want to do an estimate for the specific heat transport capacity of moist air column incoming, say flux area 1000km wide by 5km deep, velocity 50kmph?).
Title: Re: The 2017 melting season
Post by: Tigertown on March 27, 2017, 05:24:40 AM
@Hyperion

Just trying to understand here; what are you saying has changed dramatically about the TPW? Looking back a few years, this year seems to show only minor changes of late. Please clarify. 

P.S. If we get too deep into this, you are going to need to open a new thread in a new location, as opposed to renaming this one. I don't know how that is going to fly with Neven, but I guess we'll see.
Title: Re: The 2017 melting season
Post by: jai mitchell on March 27, 2017, 07:16:00 AM
these atmospheric river events are several days worth and transport water vapor on the order of 8X10^7 kg/s into the arctic.  Called Qr in the following paper http://www.meteo.psu.edu/~sxl31/papers/Baggett_Lee_Feldstein_2016.pdf (http://www.meteo.psu.edu/~sxl31/papers/Baggett_Lee_Feldstein_2016.pdf)

there is a separate thread in the science section for this discussion. 
http://forum.arctic-sea-ice.net/index.php/topic,1874.0.html (http://forum.arctic-sea-ice.net/index.php/topic,1874.0.html)
Title: Re: Roundhouse punches from the ApocalyptoKraken
Post by: slow wing on March 27, 2017, 08:41:29 AM
Thanks Hyperion, I agree that it's interesting to look at the potential contribution of atmospheric water to Arctic sea ice melt so I will take you up on your 'peer review' offer...

...
Quickstab at what this setup might mean numerically. Peer review and alternative approaches most welcome:
 ;)

1,680,000,000,000,000J
18.748 kg/sqm
200km x 50kmph (ballpark flow estimate) x 24hr = 240 000 sqkm = 240 000 000 000 sqm
240 000 000 000 sqm x 19 kg x 4200J = 19,152,000,000,000,000 Joules per day
=19.52 petajoules per day
...

That's the specific heat capacity of water - the amount of energy required to raise the temperature of 1 kg liquid water by 1 degree Kelvin \ Celsius. Better to use the heat of evaporation as the "Total precipitable water" is almost all vapour (use "Total cloud water" option to see the small part that isn't) and can melt ice by condensing. This contribution to heating the ice is much larger than the heats from temperature changes.

Water properties here. (http://www.engineeringtoolbox.com/water-thermal-properties-d_162.html)
It's actually even easier to use the ratio of heats of vaporisation to fusion.
Latent heat of melting - 334 kJ/kg
Latent heat of evaporation - 2257 kJ/kg
Ratio ~ 2257 / 334 ~ 6.76. So each kg of water vapour can, by condensing, cause the melt of nearly 7 kgs of ice.

Expressed in scientific notation, you estimated 2.4e11 m^2 of moist air entering the Arctic per day, carrying 18 kg/m^2 of water vapour, so on multiplying you say about 4e12 kg/day of water vapour entering the Arctic.

From above, this could melt 2.4e11 x 18 x 6.8 kg/day ~ 3e13 kg/day of ice.

To see if this would be a relevant amount, we should ask how many kg of ice are in the Arctic?

From PIOMAS, we see that the volume of Arctic sea ice at the end of the freeze season is around 20 000 km^3 ~ 2e13 m^3. Ice weighs around 900 kg/m^3, so this is ~ 2e16 kg of ice.

On comparing the two, it would take several hundred days to melt all the ice at the assumed rate of ingress of water vapour and assuming a large fraction of it condenses to melt ice.

  As an initial impression, I would also say that the rate of ingress you assume is anyway much larger than would be typical, perhaps by an order of magnitude or more.


So this back-of-the-envelope calculation suggests that the ingress of atmospheric water vapour into the Arctic can't account for a large fraction of the yearly ice loss. However, it wouldn't be surprising if it contributed at the percent level or maybe up to a few percent of the ice loss.

Given the observed rise in atmospheric moisture beginning around the start of 2016, this could still mean a significant rise in sea ice loss by this mechanism.

Presumably this has been studied at a more rigorous level. Does anyone know of such a study and their findings?
EDIT: already answered and it has been studied. Thanks, Jai Mitchell.
Title: Re: The 2017 melting season
Post by: romett1 on March 27, 2017, 09:49:25 AM
Latest GFS (Climate Reanalyzer) anomalies until next Monday.
"Heatwave" stays over Kara, Laptev and ESS and also higher temperatures over North Pole and Beaufort.
Title: Re: The 2017 melting season
Post by: misfratz on March 27, 2017, 10:13:31 AM
I find it all rather alarming that Siberia seems to be consistently warmer than normal. Also when looking at uni bremen there are blue patches appearing everywhere.

Ill be very impressed if there is anything more than the lowest on record this year.

the odds must be 100/1 at least.
My ballpark for the last several years has been a 1-in-4 chance of a new record each year. A lot really does depend on the weather.

While the low pressure systems over the Arctic recently have been pushing the ice away from the SIberian coast I've noted that the mean air temperature there has still been below freezing. So does that mean that open water results in a net loss of heat, or is there enough solar insolation after the equinox to see heat enter the Arctic Ocean?
Title: Re: The 2017 melting season
Post by: seaicesailor on March 27, 2017, 12:14:42 PM
I think that at this time, all new cracks refreeze, but will easily re-open soon (1 month?) and absorb sunlight with a very negative impact on ice for the whole summer, which overcomes any beneficial heat loss. It would be a different story if this happened in January.
Likewise, the absence of cracks on the American side for the time being is certainly a positive for the ice.
Title: Re: The 2017 melting season
Post by: Apocalypse4Real on March 27, 2017, 03:14:36 PM
Here is the Arctic view of the fracturing across the entire 80N area. No assurance of stability in the pack.

Note the fracturing across the top of Greenland and deeper into the Arctic Ocean. A lot of mobility that does not seem ready to slow any time soon.
Title: Re: The 2017 melting season
Post by: Buddy on March 27, 2017, 03:40:17 PM
<snip; this off-topic rant has been copied and pasted to the 2017 sea ice extent and area data (https://forum.arctic-sea-ice.net/index.php/topic,1837.msg107801.html#msg107801) thread, next time I will just delete it; N.>
Title: Re: The 2017 melting season
Post by: Hyperion on March 27, 2017, 07:39:17 PM
<snip; just this one time I've copied your off-topic rant to the What's new in Antarctica (https://forum.arctic-sea-ice.net/index.php/topic,622.msg107800.html#msg107800) thread, next time I will remove your comment, keep it short and keep it to the point (ie the 2017 melting season); N.>
Title: Re: The 2017 melting season
Post by: oren on March 27, 2017, 08:25:23 PM
Hyperion this is good stuff but should be in some other thread, not sure which though. But this stuff ain't arctic melting season.
Title: Re: The 2017 melting season
Post by: Neven on March 27, 2017, 09:12:29 PM
It took me almost 5 minutes to copy the off-topic and way too long comments by Buddy and Hyperion. I won't be doing that often as the melting (and NH gardening) season progresses. So again, my 'rules' (they are actually universal laws):

1) Every comment in the melting/freezing season threads should pertain to that subject. These are the most popular threads for readers who don't comment, so don't bother them with off-topic stuff.
2) If you have to be off-topic, be short.
3) If you're the third guy who wants to say something about the off-topic subject, say: Okay, guys, this is getting off-topic, let's go to this or that thread - or open a new one - so our discussions don't get lost and we don't bother others. It's a big forum.
4) In other threads you can go off-topic more.
5) Don't start discussions about these rules in the thread itself. PM Neven or go to the The Forum category.

It's a big forum. Don't try to stuff all your ideas, theories and opinions in this one thread. Many people come here to read about the latest near real-time news on the 2017 melting season, not about the implications, the consequences and the politics of it all. Show some respect.

Thank you, that was all.
Title: Re: The 2017 melting season
Post by: Buddy on March 27, 2017, 09:17:23 PM
<snip; this off-topic rant has been copied and pasted to the 2017 sea ice extent and area data thread, next time I will just delete it; N.>

I actually started to put it there.....wasn't SURE where it should actually go, since it relates to both Arctic and Antarctic.

My bad.....
Title: Re: The 2017 melting season
Post by: seaicesailor on March 27, 2017, 09:20:45 PM
BTW when I said absence of cracks in the American side I meant mostly the Beaufort sea. As seen in that pic posted by A4R, north of the CAA and Greenland is a complete different story, but the danger there is not so much insolation but mobility of the ice toward the Atlantic ocean as explained by A4R.
Well, insolation too, eventually   :-\
Title: Re: The 2017 melting season
Post by: slow wing on March 27, 2017, 10:05:16 PM
SeaIceSailor,

  My guess at the reason why there are no visible cracks in the Beaufort Sea at the moment is because it has been under fairly constant compression over at least the past month (http://forum.arctic-sea-ice.net/index.php/topic,1834.msg107437.html#msg107437). So the lack of cracks probably doesn't speak much to the quality, or otherwise, of the ice there.
Title: Re: The 2017 melting season
Post by: Tigertown on March 28, 2017, 04:38:05 AM
It seems a little quiet today except in the ESS and the Bering Sea.
(http://)
Title: Re: The 2017 melting season
Post by: romett1 on March 28, 2017, 11:12:06 AM
Latest GFS anomalies until next Tuesday (Climate Reanalyzer).
Kara, Laptev and ESS still anomalously warm, also Beaufort warmer than usual.
Title: Re: The 2017 melting season
Post by: johnm33 on March 28, 2017, 11:18:47 AM
"Beaufort" There's enough movement to generate cracks, but no durable cracks, looks like the ice is soft either on a small or large scale, no tensile strength. The extensive red on Nullschool suggests plenty of small cracks, and it's all close to -1.8 so rapidly refreezing where sea is exposed, thickening too, so perhaps in a couple of weeks we'll see cracks. https://www7320.nrlssc.navy.mil/hycomARC/beaufort.html   https://earth.nullschool.net/#current/ocean/surface/currents/overlay=sea_surface_temp_anomaly/orthographic=-37.81,87.19,1336/loc=-132.662,74.328 (https://www7320.nrlssc.navy.mil/hycomARC/navo/beauforticespddrf_nowcast_anim30d.gif)
Title: Re: The 2017 melting season
Post by: Jim Hunt on March 28, 2017, 11:25:49 AM
An excellent view of the recently refrozen sea ice in the East Siberian Sea this morning, courtesy of the Terra satellite:

http://GreatWhiteCon.info/2017/03/facts-about-the-arctic-in-march-2017/#comment-220587 (http://GreatWhiteCon.info/2017/03/facts-about-the-arctic-in-march-2017/#comment-220587)
Title: Re: The 2017 melting season
Post by: Tigertown on March 28, 2017, 11:33:36 AM
Latest GFS anomalies until next Tuesday (Climate Reanalyzer).
Kara, Laptev and ESS still anomalously warm, also Beaufort warmer than usual.
It is good to know what the average anomalies over the whole Arctic are running, but does anyone know what they are peaking at? I can only make out the color shades to a limited degree.
Looks like around +18oC....
(http://)
Title: Re: The 2017 melting season
Post by: TheUAoB on March 28, 2017, 11:41:31 AM
"Beaufort" There's enough movement to generate cracks, but no durable cracks, looks like the ice is soft either on a small or large scale, no tensile strength. The extensive red on Nullschool suggests plenty of small cracks, and it's all close to -1.8 so rapidly refreezing where sea is exposed, thickening too, so perhaps in a couple of weeks we'll see cracks.
Since sea-ice melts/freezes at -1.8C, if the air temperature is clamped to -1.8C, to me, that implies the enthalpy of sea-water/ice is maintaining the temperature.  Water in cracks will likely freeze over for a while, but I can't imagine much if any thickening occurring under those conditions except through ridging.
Title: Re: The 2017 melting season
Post by: Gray-Wolf on March 28, 2017, 12:59:42 PM
I have to think that this lack of fragmentation is a 'Thing'? I've been watching out for the type of fragmentation/'Crackopalypse' event to occur from late Jan onward and nothing, on the scale of recent past winters, has occurred in Beaufort?

My only clue is watching the Trans Arctic Drift, above Greenland, where we know there is 'thick, older ice, and see what is happening there? To me that areas shows the type of 'fragmentation' that I had been kind of expecting to occur across Beaufort. I have to think that the pressures are present to drive the type of 'crackopalypse event' we have seen at recent winters end but the new grown ice behaves differently to the type of 'conglomeration of varying sizes of floe glued together by FY ice' that had been present across Beaufort in previous years??

If Pancake ice is the seed for this ice than it may well have the ability to move like chain mail and absorb motion?

 Like the movement of ball pool balls compared to sheets of Styrofoam?
Title: Re: The 2017 melting season
Post by: johnm33 on March 28, 2017, 01:13:32 PM
"Beaufort" There's enough movement to generate cracks, but no durable cracks, looks like the ice is soft either on a small or large scale, no tensile strength. The extensive red on Nullschool suggests plenty of small cracks, and it's all close to -1.8 so rapidly refreezing where sea is exposed, thickening too, so perhaps in a couple of weeks we'll see cracks.

Since sea-ice melts/freezes at -1.8C, if the air temperature is clamped to -1.8C, to me, that implies the enthalpy of sea-water/ice is maintaining the temperature.  Water in cracks will likely freeze over for a while, but I can't imagine much if any thickening occurring under those conditions except through ridging.

Just to be clear I'm assuming the red, in the link above, indicates cracks exposing the sea surface, the anomoly is .3C so -1.5C sst, the airs much colder. http://www.meteociel.fr/modeles/gfse_cartes.php?ech=6&code=0&mode=9&carte=1 (http://www.meteociel.fr/modeles/gfse_cartes.php?ech=6&code=0&mode=9&carte=1)  and the thickening spreads from the CAA so I guess that's where durable cracks will appear. We'll see.
(https://www7320.nrlssc.navy.mil/hycomARC/navo/beaufortictn_nowcast_anim30d.gif)
Title: Re: The 2017 melting season
Post by: Apocalypse4Real on March 28, 2017, 03:38:16 PM
Fracturing is occurring in the Beaufort as well as the CAB. Note the attached. It may be that the entire pack is becoming more mobile due to thinner ice and wind effects.
Title: Re: The 2017 melting season
Post by: seaicesailor on March 28, 2017, 05:13:11 PM
ACNFS Hycom Sea ice drift predicted from today to Apr 2.
The situation reminds a bit to Spring 2014, with the ice drifting away from Laptev sea coasts persistently, and a lot of transport toward the Atlantic.
Title: Re: The 2017 melting season
Post by: DrTskoul on March 28, 2017, 05:19:26 PM
Yikes.  Somebody close the doors, the draft is killing us...
Title: Re: The 2017 melting season
Post by: oren on March 28, 2017, 05:32:00 PM
johnm33's wonderful animation tells it all, the Beaufort is thickening and seems to be compacting as well, plus there is almost no gyre, I am guessing this is why it's not fracturing, while all the old ice in the CAB is tearing apart and spilling down the Fram.
I wonder if the Beaufort will manage to start late this year - I doubt it but it's becoming a possibility. Might balance the Beaufort's lack of MYI and high vulnerability to early meltout.
Title: Re: The 2017 melting season
Post by: seaicesailor on March 28, 2017, 05:47:11 PM
If PIOMAS captures well all the melting that has been going on west of Svalbard, I don't think the volume increase will be in the high range.
Title: Re: The 2017 melting season
Post by: romett1 on March 28, 2017, 06:37:50 PM
If PIOMAS captures well all the melting that has been going on west of Svalbard, I don't think the volume increase will be in the high range.

What seemed to be a decent block 120 km long and about 50 km wide at widest point, disappeared in just couple of days. Of course it's not surprising, as the warm current has been there for a very long time.
Title: Re: The 2017 melting season
Post by: seaicesailor on March 28, 2017, 06:50:07 PM
If PIOMAS captures well all the melting that has been going on west of Svalbard, I don't think the volume increase will be in the high range.

What seemed to be a decent block 120 km long and about 50 km wide at widest point, disappeared in just couple of days. Of course it's not surprising, as the warm current has been there for a very long time.
Yes, and I wonder how permanent this is (the warm currents this strong). Can the ice affect the currents somehow in short term? I would say no but locally they may force the salty water sink in a more southernly location permitting the ice pack extend more... or just the opposite reinforce them for this summer (after all more sinking is one of the engines that drives more water from South)
Title: Re: The 2017 melting season
Post by: JimboOmega on March 28, 2017, 08:48:49 PM
It seems a little quiet today except in the ESS and the Bering Sea.
(http://)

Are those melt ponds (in the ESS)? In March? It's been anomalously warm... but not that (above freezing) warm. Right?
Title: Re: The 2017 melting season
Post by: Neven on March 28, 2017, 10:10:07 PM
Here's an update to that animation of the sea ice retreat from the southwestern shore of Novaya Zemlya (Kara Sea). Things haven't moved much for the past couple of days, and things might stay that way for a while longer, as this region seems to remain in the centre of a low-pressure area for the coming week.
Title: Re: The 2017 melting season
Post by: Tor Bejnar on March 29, 2017, 01:09:58 AM
The longer that bit of water remains ice-free, the less likely ice will re-cover it, as
1) the open water is prone to solar gain
2) the end of the (local) freezing season approaches.

I'm sure the surface re-freezing remains a possibility, though.  (It's still cold out there!)
Title: Re: The 2017 melting season
Post by: VeliAlbertKallio on March 29, 2017, 01:17:37 AM
As per animation, the continued southward drift from the Baffin Bay remains one of the sea ice leaking points from the Arctic joining the Fram Strait, the Barentz Sea and the Kara Sea for rapid and early loss of sea ice. The Baffin Bay sea ice loss contribution may not be continuous, but it impacts the onset of darkening and melting of Greenland once sun gets stronger. It suggests me that the area is rapidly clearing from ice by sea ice transport - which is probably early.

ACNFS Hycom Sea ice drift predicted from today to Apr 2.
The situation reminds a bit to Spring 2014, with the ice drifting away from Laptev sea coasts persistently, and a lot of transport toward the Atlantic.
Title: Re: The 2017 melting season
Post by: romett1 on March 29, 2017, 11:54:57 AM
Latest GFS anomalies until next Wednesday (Climate Reanalyzer). Added 5-day forecast, which is still red all the way from Kara Sea to Beaufort.
Title: Re: The 2017 melting season
Post by: iceman on March 29, 2017, 12:13:14 PM
The longer that bit of water remains ice-free, the less likely ice will re-cover it, as
1) the open water is prone to solar gain
2) the end of the (local) freezing season approaches.

I'm sure the surface re-freezing remains a possibility, though.  (It's still cold out there!)

I question whether the insolation anomaly in Kara is greater than the heat loss from open water to atmosphere.  If the latter is especially large, any refreeze could persist longer than usual.
     In contrast, the low ice cover in Okhotsk looks to heavily favor insolation at that lower latitude and this time of year.  But the excess heat gain there won't have much effect on the central Arctic.
Title: Re: The 2017 melting season
Post by: Tor Bejnar on March 29, 2017, 12:46:20 PM
Thanks, iceman, for adding that important piece of the puzzle.
Title: Re: The 2017 melting season
Post by: Neven on March 29, 2017, 02:06:53 PM
Slightly more movement in the past two days in the Kara...
Title: Re: The 2017 melting season
Post by: oren on March 29, 2017, 05:33:24 PM
Latest GFS anomalies until next Wednesday (Climate Reanalyzer). Added 5-day forecast, which is still red all the way from Kara Sea to Beaufort.
romett1, thanks for posting the GFS anomalies+forecast. It seems that every time I look at the table the forecast a few days out shows the anomaly lessening. But every time you post an update the anomaly stays high. Is it just my imagination? Or is the GFS underestimating the forecast anomaly?
Title: Re: The 2017 melting season
Post by: romett1 on March 29, 2017, 06:11:45 PM
Latest GFS anomalies until next Wednesday (Climate Reanalyzer). Added 5-day forecast, which is still red all the way from Kara Sea to Beaufort.
romett1, thanks for posting the GFS anomalies+forecast. It seems that every time I look at the table the forecast a few days out shows the anomaly lessening. But every time you post an update the anomaly stays high. Is it just my imagination? Or is the GFS underestimating the forecast anomaly?

I have noticed same thing. I guess they are slightly conservative about days 6 and 7 and updating higher, when they feel more confident.
I hope the table is useful for forum readers, I was bit worried about CFS April - May long-term forecast (posted by FishOutofWater).
Title: Re: The 2017 melting season
Post by: Lord M Vader on March 29, 2017, 06:13:37 PM
Not only is there movement in Kara, but also in the ice export through FJL and Fram. The remaining thick ice will be under fire for a while!
Title: Re: The 2017 melting season
Post by: Tigertown on March 29, 2017, 06:19:21 PM
Latest GFS anomalies until next Wednesday (Climate Reanalyzer). Added 5-day forecast, which is still red all the way from Kara Sea to Beaufort.
romett1, thanks for posting the GFS anomalies+forecast. It seems that every time I look at the table the forecast a few days out shows the anomaly lessening. But every time you post an update the anomaly stays high. Is it just my imagination? Or is the GFS underestimating the forecast anomaly?
One concern, which may or may not have a bearing on the matter:
I think they take the average from the whole Arctic circle, which can be a little deceptive. You might find a +20oC anomaly in an area over the ocean and sea ice, but it might be really cold in another area, which could even be over land. This drops the average, which then fails to represent how detrimental the anomaly is to the ice. A good fix is posting the map along with the table. Neven is always pointing out that there are many people dropping in on this thread, so it is especially good for them to comprehend this, as I am sure the regulars here don't need it to be explained. BTW, good job romett1.
Title: Re: The 2017 melting season
Post by: JimboOmega on March 29, 2017, 06:47:28 PM
When it comes to these temperature anomalies... which I've been watching since at least November... I really have to wonder how much they matter this time of year (over ice, in particular).

If there's a patch of the arctic where normally it is -40 C/F, but instead due to huge anomalies it is -10 C, so what? It doesn't melt, melt ponds don't happen... I feel like the thermodynamics don't change...  until it gets above freezing.

Do we expect anything to come of these high anomalies, where temperatures still stay below freezing?
Title: Re: The 2017 melting season
Post by: Peter Ellis on March 29, 2017, 06:56:39 PM
Yes, ice fails to thicken as much as normal if the temperature is not low enough.
Title: Re: The 2017 melting season
Post by: DrTskoul on March 29, 2017, 07:47:54 PM
When it comes to these temperature anomalies... which I've been watching since at least November... I really have to wonder how much they matter this time of year (over ice, in particular).

If there's a patch of the arctic where normally it is -40 C/F, but instead due to huge anomalies it is -10 C, so what? It doesn't melt, melt ponds don't happen... I feel like the thermodynamics don't change...  until it gets above freezing.

Do we expect anything to come of these high anomalies, where temperatures still stay below freezing?

Heat flux out of the ice ( if we assume linear force formulation -  flux proportional to ΔT) is a quarter roughly compare to normal... it takes four times as long to thicken at the same level..
Title: Re: The 2017 melting season
Post by: Lord M Vader on March 29, 2017, 07:56:13 PM
While this stuff might belong to the frezzing thread, I think it's a valuable view for the upcoming melting season.

Here is Zack Labe's tweet from today which shows how the temperature anomalies for October to December have evolved from 1979 and onward. Hat tip to him! :) I think we'll see a shift in the future to March being the coldest month during winter as polar amplification will continue and worsen.

(https://pbs.twimg.com/media/C8GNm_6U8AEMtaW.jpg:large)
Title: Re: The 2017 melting season
Post by: Andre on March 29, 2017, 08:24:26 PM
romett1, thanks for posting the GFS anomalies+forecast. It seems that every time I look at the table the forecast a few days out shows the anomaly lessening. But every time you post an update the anomaly stays high. Is it just my imagination? Or is the GFS underestimating the forecast anomaly?

Fully agreed! I really enjoy your regular contribution romett1 and hope you will keep it up. It is easy to lose sight of the daily values, when watching the animation, which makes me appreciate your concise table format even more! Thanks for the regular updates!
Title: Re: The 2017 melting season
Post by: jdallen on March 29, 2017, 11:16:58 PM
When it comes to these temperature anomalies... which I've been watching since at least November... I really have to wonder how much they matter this time of year (over ice, in particular).

If there's a patch of the arctic where normally it is -40 C/F, but instead due to huge anomalies it is -10 C, so what? It doesn't melt, melt ponds don't happen... I feel like the thermodynamics don't change...  until it gets above freezing.

Do we expect anything to come of these high anomalies, where temperatures still stay below freezing?

Heat flux out of the ice ( if we assume linear force formulation -  flux proportional to ΔT) is a quarter roughly compare to normal... it takes four times as long to thicken at the same level..


... presuming enthalpy remains constant.  The problem is, we have heat flow from depth, such that below a given temperature threshold, the ice won't thicken at all, because heat is replenished at the water/ice interface faster than it can be transferred out of the ice to atmosphere.  At -10C, ice more than 1M thick will actually start melting from the bottom, given enough time.
Title: Re: The 2017 melting season
Post by: Neven on March 29, 2017, 11:43:52 PM
Do we expect anything to come of these high anomalies, where temperatures still stay below freezing?


Yes, earlier melt onset due to downwelling longwave radiation (see here (http://onlinelibrary.wiley.com/doi/10.1002/2016GL069330/full)). Or pre-pre-conditioning, as sea ice sailor called it earlier today (http://forum.arctic-sea-ice.net/index.php/topic,382.msg107966.html#msg107966) (half-kiddingly, but aptly).
Title: Re: The 2017 melting season
Post by: DrTskoul on March 29, 2017, 11:53:18 PM
When it comes to these temperature anomalies... which I've been watching since at least November... I really have to wonder how much they matter this time of year (over ice, in particular).

If there's a patch of the arctic where normally it is -40 C/F, but instead due to huge anomalies it is -10 C, so what? It doesn't melt, melt ponds don't happen... I feel like the thermodynamics don't change...  until it gets above freezing.

Do we expect anything to come of these high anomalies, where temperatures still stay below freezing?

Heat flux out of the ice ( if we assume linear force formulation -  flux proportional to ΔT) is a quarter roughly compare to normal... it takes four times as long to thicken at the same level..


... presuming enthalpy remains constant.  The problem is, we have heat flow from depth, such that below a given temperature threshold, the ice won't thicken at all, because heat is replenished at the water/ice interface faster than it can be transferred out of the ice to atmosphere.  At -10C, ice more than 1M thick will actually start melting from the bottom, given enough time.

The implicit assumption was the bottom was at equilibrium... if not then absolutely it can melt. The same way that ice does not initially form until air temperature is below -10...
Title: Re: The 2017 melting season
Post by: dosibl on March 30, 2017, 12:06:36 AM
I've been watching the Hycom CICE thickness plots (https://www7320.nrlssc.navy.mil/hycomARC/arctic.html (https://www7320.nrlssc.navy.mil/hycomARC/arctic.html)) while I wait for the next PIOMAS update, so I decided to download all the images and try to extract some data from them.

For each day I get the total number of colored pixels, as well as the thickness associated with that color (ranging from 0 to 5 meters). With those numbers its pretty straightforward to graph total thickness as well as average thickness.

Right now the numbers are for all ice shown in the image, I'm hoping to eventually produce the numbers by region, I'm particularly interested to see the overall percentage of ice that is in the Fram.
Title: Re: The 2017 melting season
Post by: misfratz on March 30, 2017, 12:32:58 AM
Latest GFS anomalies until next Wednesday (Climate Reanalyzer). Added 5-day forecast, which is still red all the way from Kara Sea to Beaufort.
romett1, thanks for posting the GFS anomalies+forecast. It seems that every time I look at the table the forecast a few days out shows the anomaly lessening. But every time you post an update the anomaly stays high. Is it just my imagination? Or is the GFS underestimating the forecast anomaly?
I have noticed same thing. I guess they are slightly conservative about days 6 and 7 and updating higher, when they feel more confident.
I hope the table is useful for forum readers, I was bit worried about CFS April - May long-term forecast (posted by FishOutofWater).
Just a note about the forecast - these figures will be purely from the model, with no human intervention, so it's not a matter of the human forecasters becoming more confident.

If the model has a climatological bias to colder temperatures then you would expect that to become established during the course of the forecast. An example of the sort of thing would be if, say, the cloud forcing was too strong to produce too much cooling. It will take a few days for the model to diverge from the reality of the initial conditions to its biased model climatology.

Normally modelling groups publish papers on major model upgrades, so you might be able to find out whether this model has a climatological cold bias over the Arctic.
Title: Re: The 2017 melting season
Post by: ipexnet on March 30, 2017, 01:17:36 AM
When it comes to these temperature anomalies... which I've been watching since at least November... I really have to wonder how much they matter this time of year (over ice, in particular).

If there's a patch of the arctic where normally it is -40 C/F, but instead due to huge anomalies it is -10 C, so what? It doesn't melt, melt ponds don't happen... I feel like the thermodynamics don't change...  until it gets above freezing.

Do we expect anything to come of these high anomalies, where temperatures still stay below freezing?

More Energy = Less Ice
Title: Re: The 2017 melting season
Post by: LRC1962 on March 30, 2017, 02:08:08 AM
When it comes to these temperature anomalies... which I've been watching since at least November... I really have to wonder how much they matter this time of year (over ice, in particular).

If there's a patch of the arctic where normally it is -40 C/F, but instead due to huge anomalies it is -10 C, so what? It doesn't melt, melt ponds don't happen... I feel like the thermodynamics don't change...  until it gets above freezing.

Do we expect anything to come of these high anomalies, where temperatures still stay below freezing?

More Energy = Less Ice
A simple mind example. Take 2 freezers and 2 cows. Set one freezer at -10 and one at -40. Put one cow (both same size and weight) in each freezer. The cow in the freezer set at -10 will take much longer to freeze and even when it is totally frozen, a much shorter time to thaw then the one set at -40.
Now the Arctic is a much more complex system then a freezer because you have a lot of kinetic energy involved also, but I do think that does help get the point across that you can be frozen and then you can be really frozen.
Title: Re: The 2017 melting season
Post by: Shared Humanity on March 30, 2017, 02:34:02 AM
When it comes to these temperature anomalies... which I've been watching since at least November... I really have to wonder how much they matter this time of year (over ice, in particular).

If there's a patch of the arctic where normally it is -40 C/F, but instead due to huge anomalies it is -10 C, so what? It doesn't melt, melt ponds don't happen... I feel like the thermodynamics don't change...  until it gets above freezing.

Do we expect anything to come of these high anomalies, where temperatures still stay below freezing?

More Energy = Less Ice

Simple and to the point.
Title: Re: The 2017 melting season
Post by: subgeometer on March 30, 2017, 04:04:57 AM
These cracks or shears or whatever are spreading and getting worse. They have no respect for the NP region either. Only the the thick, robust, durable, mighty, 93 cm ice in the Beaufort stands a chance against these. ;)
(http://)

Hee''s an animation of the ESS from March 11-29 where the Bremen Thin Ice map at https://seaice.uni-bremen.de/thin-ice-thickness/ has been showing a persistent region of thin ice. Despite the ice pushing away from the Eurasian coast it's not apparently thickening up much else where, and the ongoing heatwave on the Eusaian side will not allow much new ice growth
Title: Re: The 2017 melting season
Post by: Tigertown on March 30, 2017, 04:55:13 AM
JAXA volume sitting all alone now for this year, well below former years. This chart has been trending about 1,000 to 1,200 km3 below PIOMAS. I am sure we are all looking forward to the next PIOMAS update, though maybe a little anxiously.
(http://)
Title: Re: The 2017 melting season
Post by: Tigertown on March 30, 2017, 05:55:51 AM
So much for no cracks in the Beaufort.(first pic.)
BTW: Finally got that hole at the NP fixed.(second pic.)  ;)
(http://)
Title: Re: The 2017 melting season
Post by: jdallen on March 30, 2017, 07:54:12 AM
EDIT:  Use the links - they give you a better sense of things than the screen shots I captured.

EOSDIS Band31/night image, squashed to 225K-271K.

The red-to-yellow bits are where we are in trouble... and there is a lot of it.

https://worldview.earthdata.nasa.gov/?p=arctic&l=MODIS_Terra_CorrectedReflectance_TrueColor(hidden),VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_Brightness_Temp_Band31_Night(opacity=0.5,palette=rainbow_1,min=224.9,max=271.1,squash),Land_Mask,AMSR2_Sea_Ice_Brightness_Temp_6km_89H(hidden,palette=orange_1,min=228,229,max=272,273,squash)&t=2017-03-28&z=3&v=-9751645.996095065,-5382670.466787146,10810274.003904935,3907057.5332128536
Title: Re: The 2017 melting season
Post by: jdallen on March 30, 2017, 07:58:52 AM
2015 & 2016 for comparison.

https://worldview.earthdata.nasa.gov/?p=arctic&l=MODIS_Terra_CorrectedReflectance_TrueColor(hidden),VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_Brightness_Temp_Band31_Night(opacity=0.5,palette=rainbow_1,min=224.9,max=271.1,squash),Land_Mask,AMSR2_Sea_Ice_Brightness_Temp_6km_89H(hidden,palette=orange_1,min=228,229,max=271,272,squash)&t=2016-03-28&z=3&v=-10360925.996095065,-4197219.80012048,10200994.003904935,4289692.19987952

https://worldview.earthdata.nasa.gov/?p=arctic&l=MODIS_Terra_CorrectedReflectance_TrueColor(hidden),VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_Brightness_Temp_Band31_Night(opacity=0.5,palette=rainbow_1,min=224.9,max=271.1,squash),Land_Mask,AMSR2_Sea_Ice_Brightness_Temp_6km_89H(hidden,palette=orange_1,min=228,229,max=271,272,squash)&t=2015-03-28&z=3&v=-9914261.037791336,-3750554.841816751,10647658.962208664,4736357.158183249
Title: Re: The 2017 melting season
Post by: romett1 on March 30, 2017, 09:41:01 AM
Thanks for the good words. Latest GFS anomalies until next Thursday (Climate Reanalyzer).
Added 5-day forecast, still red all the way from Kara Sea to Beaufort.
Also noticed that Kara Sea near Novaya Zemlya (where there is open water) is quite windy Mar 30 - Apr 6.
Title: Re: The 2017 melting season
Post by: Tigertown on March 30, 2017, 04:42:31 PM
The Bering Sea ice has been holding the extent up for a while now, even inflating it some, but is getting really thin and dispersed now.
CLICK IMAGE PLEASE
(http://)
Title: Re: The 2017 melting season
Post by: Lord M Vader on March 30, 2017, 06:48:17 PM
Seems like Laptev Sea will see temperatures briefly exceeding the freeze point in the next 24 hours. Questonable if there will be any precipitation in form of rain or sleet there.
Title: Re: The 2017 melting season
Post by: MusicScienceGuy on March 30, 2017, 07:01:59 PM
Although JAXA is up a bit, it sure looks, to me, like the whole Arctic ice cap is amazingly thin; from Hudson's Bay, to Fram Strait, and especially to the whole north of Siberia area.
I hereby predict that large areas will start to drop below the 15% ice coverage level in these areas in the next couple of weeks and JAXA will dive.

If so, the followup question is, at what point will the mainstream media take notice?

Your thoughts?
Title: Re: The 2017 melting season
Post by: dnem on March 30, 2017, 07:22:42 PM
Although JAXA is up a bit, it sure looks, to me, like the whole Arctic ice cap is amazingly thin; from Hudson's Bay, to Fram Strait, and especially to the whole north of Siberia area.
I hereby predict that large areas will start to drop below the 15% ice coverage level in these areas in the next couple of weeks and JAXA will dive.

If so, the followup question is, at what point will the mainstream media take notice?

Your thoughts?
Title: Re: The 2017 melting season
Post by: dnem on March 30, 2017, 07:23:03 PM
Never.  Anything going on in the arctic will be treated as a curiosity and get cursory coverage.  Only unambiguously anomalous and hugely disruptive extreme weather in densely populated parts of the highly developed world will cause the MSM to take notice.

Sorry for the diversion from the thread.
Title: Re: The 2017 melting season
Post by: Thomas Barlow on March 30, 2017, 07:51:09 PM
Although JAXA is up a bit, it sure looks, to me, like the whole Arctic ice cap is amazingly thin; from Hudson's Bay, to Fram Strait, and especially to the whole north of Siberia area.
I hereby predict that large areas will start to drop below the 15% ice coverage level in these areas in the next couple of weeks and JAXA will dive.

If so, the followup question is, at what point will the mainstream media take notice?

Your thoughts?

I don't think thickness and volume are hugely worse of than the last few years according to this below. However, all these measures are within a margin of error, and not precise, that's why I like the big thick line on this one. More realistic assessment.
But still, among the lowest, and should be a warning sign. The media will report it, some will denounce it as hyperbole, others will overstate it, and make us all look silly. Fact is, it's not good, but not off the cliff quite yet (I say that as someone who was convinced we would head off a cliff this year... not sure yet. Won't know until July or August really. No-one will. It's a fun guessing game, but that's about all.)

http://polarportal.dk/en/havisen-i-arktis/nbsp/sea-ice-extent (http://polarportal.dk/en/havisen-i-arktis/nbsp/sea-ice-extent)
Title: Re: The 2017 melting season
Post by: dosibl on March 30, 2017, 07:57:17 PM
@Thomas That graph doesn't line up with what I'd expect just based on the FDD anomaly delta between the two years.
Title: Re: The 2017 melting season
Post by: Tor Bejnar on March 30, 2017, 08:26:43 PM
The Arctic Penguin (PIOMAS (https://sites.google.com/site/arctischepinguin/home/piomas)) doesn't agree with DMI (at least as to the relation of 2016 ice volume to other years).
Title: Re: The 2017 melting season
Post by: Buddy on March 30, 2017, 08:31:19 PM
The Arctic Penguin (PIOMAS) doesn't agree with DMI (at least as to the relation of 2006 ice volume to other years).

Yikeesss.  So we're about 10% below the record low level for this time of year.  That's not good...
Title: Re: The 2017 melting season
Post by: Tigertown on March 30, 2017, 08:50:02 PM
We should get a PIOMAS update within a week. I think volume should still be about 1,000 km3 below last year for the date. The melt season is going to be a bad one, but a couple weeks from now is a little early to expect it to really kick in with full force. Once it does get going, we might just find out how inaccurate some of the thickness charts are. Either way, the ice has very weak bonds to say the least, and when it gets torn apart, won't last long. Export will also flow freely this summer.
Title: Re: The 2017 melting season
Post by: Lord M Vader on March 30, 2017, 09:25:00 PM
Latest forecast runs suggests more high pressure dominated weather in the foreseeable future. If easterlies over Canadian Arctic will emerge we might get an early opening of the Beaufort Sea. Seems like temps should start to rise significantly soon as spring emerges northward.

The thin ice in Berings Sea will likely survive for another 10 days before a cyclone might smash through the ice with a significant reduction in sea ice extent.
Title: Re: The 2017 melting season
Post by: LRC1962 on March 30, 2017, 09:46:31 PM
I don't think thickness and volume are hugely worse of than the last few years according to this below. However, all these measures are within a margin of error, and not precise, that's why I like the big thick line on this one. More realistic assessment.
The Arctic Penguin (PIOMAS (https://sites.google.com/site/arctischepinguin/home/piomas)) doesn't agree with DMI (at least as to the relation of 2016 ice volume to other years).

In either case one factor is missed. As we have been seen throughout the freezing, a lot of MYI thick ice has been sent through the Fram. That means no matter how thick what ice is left is young ice. That means high saline/contaminated content in that ice because it takes a few ice to 'purify' it. that means if there turns out to be a big melt off this melting season, it can not last much longer then any other of the ice that is around.
Granted that is a predicated on weather conditions in that particular region.
Title: Re: The 2017 melting season
Post by: Hyperion on March 30, 2017, 10:26:34 PM
Seems like Laptev Sea will see temperatures briefly exceeding the freeze point in the next 24 hours. Questonable if there will be any precipitation in form of rain or sleet there.

Au contraire mon Ami  ::) . Snowing and sleeting its tits off I'm Afraid.

Its copping a roundhouse right hook from an Atlantic tropical water giant. below we have the images of 10kg/sqm flow of 100% relative humidity right up to at least 12km coming in off the continent at over 20 knots.
Title: Re: The 2017 melting season
Post by: Hyperion on March 30, 2017, 10:34:40 PM
Lower down and temps at 1000hpa - a couple of hundred metres off the ground.
This flow seems about 1000km wide. Anyone care to estimate how much energy its dumping?
Thats probably snow on the water, not refreeze people are noticing. And with all the photons being emitted by the water vapour as it freezes in the sky, It would not even surprize me if there were melt ponds.
Title: Re: The 2017 melting season
Post by: Cate on March 30, 2017, 11:41:49 PM
Big low ripping up the ice at the moment. The Northwest Atlantic iceberg field is moving down into Titanic territory. Sea ice now extends hundreds of km east of Newfoundland, putting offshore oil-drilling operations into caution mode.
Title: Re: The 2017 melting season
Post by: Thomas Barlow on March 30, 2017, 11:59:55 PM
@Thomas That graph doesn't line up with what I'd expect just based on the FDD anomaly delta between the two years.

The Arctic Penguin doesn't agree with DMI (at least as to the relation of 2016 ice volume to other years).

All these measures are within a large margin of error, and not precise. They are just fairly good indicators of a general trend, not precision analyses.
Title: Re: The 2017 melting season
Post by: VeliAlbertKallio on March 31, 2017, 01:03:41 AM
NB. JAXA graph shows a virtually continuous all-time lowest sea ice volume since the closing days of summer. Its easy to look at years in isolation (i.e. 2017) but the continuous lowest volume has been in place since the last August. Only very brief periods sea ice volume has been second worst. I would account these short periods 100% to uncertainties within the variable ice volume fluctuations and certain indicator of the lowest ever volume of sea ice - but an artifact only if JAXA model's assumptions had a systematic error (flaw) that exaggerated the ice volume reduction throughout this period (highly unlikely). Furthermore, the sea ice look is supportive of thin, soft, newly formed sea ice which has been bending and breaking easily throughout the winter. This taken into account, plus the close-to-sea-level altitude's unusual warmth (regular inversion of air temperature cooling from the surface rather than one of the past), rising methane levels and the air humidity over the entire Arctic, I do not consider JAXA sea ice volume model having any error and sea ice is truly as bad as it looks and as the models show. To hope otherwise, is just nothing more than a false Trumpian hope that there ain't anything wrong in the Arctic...

JAXA volume sitting all alone now for this year, well below former years. This chart has been trending about 1,000 to 1,200 km3 below PIOMAS. I am sure we are all looking forward to the next PIOMAS update, though maybe a little anxiously.
(http://)
Title: Re: The 2017 melting season
Post by: Hyperion on March 31, 2017, 01:11:25 AM
Latest forecast runs suggests more high pressure dominated weather in the foreseeable future. If easterlies over Canadian Arctic will emerge we might get an early opening of the Beaufort Sea. Seems like temps should start to rise significantly soon as spring emerges northward.

The thin ice in Berings Sea will likely survive for another 10 days before a cyclone might smash through the ice with a significant reduction in sea ice extent.

Not so sure easterlies are likely or needed. The South-Southwest flow in the jets (red arrow and higher altitudes) being belt driven by this big nth pacific low is strong from ~1km altitude to over six. Looks likely this BIG hammerblow of warm wet air is going to get caught in it and run the Beaufort and CAA. The indigenous Totem Pole TerrorHawk over the great lakes is just a feint. And a warning. Hi Veli 8).
Reckon that Bering ice is just flush-mush Vader. Its been streaming out of the Bering and melting constantly. Good chance that cyclone will rip it up PROPER within a week. ;D

3km altitude winds and Total Precipitable Water at all altitudes per sqm:
Title: Re: The 2017 Melting Season
Post by: Feeltheburn on March 31, 2017, 02:17:46 AM
Just in time LOL, the high was at around 1.6 Celsius / 36F

( and there is still water to see for weeks now and most of the time it was much more open water than right now )


What does the web cam in Barrow look like now?
Title: Re: The 2017 melting season
Post by: slow wing on March 31, 2017, 02:48:07 AM
WorldView shows the big tears in the ESS and Laptev Sea and the exposed water gaps next to them.

Compare with last year on the same date: the outer boundary of the fast ice was still visible as a crack but the ocean side still had solid ice right next to the crack (albeit with some smaller fractures visible).

EDIT:
2015 was similar to last year.

A bit more action was seen in the Laptev in 2014 although less dramatic than this year and, again, there was no big water gap in the ESS.
Title: Re: The 2017 melting season
Post by: DrTskoul on March 31, 2017, 02:54:16 AM
Much worse this year....
Title: Re: The 2017 melting season
Post by: Tigertown on March 31, 2017, 05:51:01 AM
Whatever the actual thickness of the thickest sea ice is, we can observe how it is flowing. It is headed to the Fram and has all season to get there. I can't imagine a situation like this ever happening before, with the thickest ice in the Arctic being this free flowing, and I don't see any surviving this summer. I think this to actually be much more important than whether or not the extent drops below 1 million km2.
(http://)
Title: Re: The 2017 melting season
Post by: Bruce Steele on March 31, 2017, 07:39:58 AM
Tigertown, There are still four ITP WHOI buoys reporting locations. Three in the Beaufort gyre 97, 98, 99 and  93 trapped into fast ice on the north coast of Svalbard.  The thing I find intriguing  is that none of the reporting buoys in the Beaufort gyre show the Northwest thick ice drift modeled in your last post. I have to believe buoys sending real time data over models in this case.
 I like to watch the temp /salinity contours but sadly we only have one of the above listed buoys still sending T/S profiles this year.

http://www.whoi.edu/page.do?pid=155136 (http://www.whoi.edu/page.do?pid=155136)

This buoy is sitting just North of McClure Strait and should show northward drift if the model was representing current conditions

http://www.whoi.edu/page.do?pid=155156 (http://www.whoi.edu/page.do?pid=155156)
Title: Re: The 2017 melting season
Post by: Lord M Vader on March 31, 2017, 09:05:08 AM
Decent big high pressure at 1035 hpa to cover virtually the whole Arctic basin in about a week or so according to 00z op ECMWF run. Might push back some thick ice into the safe heaven again if the forecast holds :)
Title: Re: The 2017 melting season
Post by: romett1 on March 31, 2017, 10:08:16 AM
Latest GFS anomalies until next Friday and 5-day forecast (Climate Reanalyzer).
Kara Sea still windy near Novaya Zemlya (where there is open water).
Also strong winds at Fram Strait Apr 6 - Apr 7 and near Bering Strait Apr 7.
Title: Re: The 2017 Melting Season
Post by: Jim Hunt on March 31, 2017, 11:36:06 AM
What does the web cam in Barrow look like now?

FYI it's now officially the Utqiaġvik (Barrow) web cam. What do you suppose this image proves?
Title: Re: The 2017 melting season
Post by: Rick Aster on March 31, 2017, 03:27:41 PM
On the northeast corner of the Bering Sea, the Nome Airport shows a temperature of 9 F, with the Weather Underground forecast temperatures -3 to 20 F for the next week before a warmup arrives. That's about 5 F below historical average. I would guess that would be cold enough to allow the Bering Sea ice extent to hold steady. The eastern Bering Sea is one of the few areas in the Arctic to be colder than average right now.

By contrast, farther north in Utqiagvik (Barrow) the temperature of -14.5 F is near average.
Title: Re: The 2017 melting season
Post by: Cate on March 31, 2017, 03:35:52 PM
Driven by that huge nor-easter, pack ice is moving into the harbour of St John's, Newfoundland today. This is very rare---I remember it happening in 1974, and maybe again in the 1980s.

https://twitter.com/PaulKinsman/status/847800660171120642
Title: Re: The 2017 melting season
Post by: Tigertown on March 31, 2017, 03:58:05 PM
Tigertown, There are still four ITP WHOI buoys reporting locations. Three in the Beaufort gyre 97, 98, 99 and  93 trapped into fast ice on the north coast of Svalbard.  The thing I find intriguing  is that none of the reporting buoys in the Beaufort gyre show the Northwest thick ice drift modeled in your last post. I have to believe buoys sending real time data over models in this case.
 I like to watch the temp /salinity contours but sadly we only have one of the above listed buoys still sending T/S profiles this year.

[url]http://www.whoi.edu/page.do?pid=155136[/url] ([url]http://www.whoi.edu/page.do?pid=155136[/url])

This buoy is sitting just North of McClure Strait and should show northward drift if the model was representing current conditions

[url]http://www.whoi.edu/page.do?pid=155156[/url] ([url]http://www.whoi.edu/page.do?pid=155156[/url])
I really don't know what the explanation for that is. We are looking at a vast area here and it may just be a matter of exact location of the buoys. I know that the majority of the ice above Greenland and the CAA is moving toward the Fram.
CLICK IMAGE TO ACTIVATE
(http://)
Title: Re: The 2017 melting season
Post by: Tigertown on March 31, 2017, 04:02:11 PM
Also, on HYCOM.
(http://)
Title: Re: The 2017 melting season
Post by: Bruce Steele on March 31, 2017, 04:20:31 PM
Tigertown, Maybe the buoys are too far west to be moving yet? I don't know. Will watch to see if they start going north over the next couple weeks .  The ice over Greenland is certainly moving towards the Fram. 
Title: Re: The 2017 melting season
Post by: Tigertown on March 31, 2017, 04:34:13 PM
Tigertown, Maybe the buoys are too far west to be moving yet? I don't know. Will watch to see if they start going north over the next couple weeks .  The ice over Greenland is certainly moving towards the Fram.
Also, it seems that the ice over the CAA is pulling free slowly from the one side, as opposed to all moving together.
Title: Re: The 2017 Melting Season
Post by: Feeltheburn on March 31, 2017, 04:59:23 PM
What does the web cam in Barrow look like now?

FYI it's now officially the Utqiaġvik (Barrow) web cam. What do you suppose this image proves?

Thanks. I was just curious since there was visible water at the beginning of melt season topic. Looks like now there isn't.
Title: Re: The 2017 Melting Season
Post by: epiphyte on March 31, 2017, 05:17:30 PM
What does the web cam in Barrow look like now?

FYI it's now officially the Utqiaġvik (Barrow) web cam. What do you suppose this image proves?

Thanks. I was just curious since there was visible water at the beginning of melt season topic. Looks like now there isn't

I think that's because there's been not much to drive drift in any direction for quite a while. No upheaval / ridging either - that ice looks like you could sweep it off and play hockey on it.
Title: Re: The 2017 melting season
Post by: Tor Bejnar on March 31, 2017, 06:17:34 PM
This is pancake ice on Lake Michigan (http://epod.usra.edu/blog/2017/03/pancake-ice-on-lake-michigan.html), but it too would look smooth from a satellite's perspective, and (even if thickened to 93 cm) I wouldn't be tempted to play ice hockey on it! 
(http://epod.usra.edu/.a/6a0105371bb32c970b01b7c8dddf80970b-pi)
(from today's Earth Science Picture of the Day (http://epod.usra.edu/))
Title: Re: The 2017 melting season
Post by: epiphyte on March 31, 2017, 10:15:03 PM
This is pancake ice on Lake Michigan ([url]http://epod.usra.edu/blog/2017/03/pancake-ice-on-lake-michigan.html[/url]), but it too would look smooth from a satellite's perspective, and (even if thickened to 93 cm) I wouldn't be tempted to play ice hockey on it! 
([url]http://epod.usra.edu/.a/6a0105371bb32c970b01b7c8dddf80970b-pi[/url])
(from today's Earth Science Picture of the Day ([url]http://epod.usra.edu/[/url]))


Neither would I - but I was looking at the webcam!
Title: Re: The 2017 melting season
Post by: Neven on April 01, 2017, 12:04:14 AM
Northern Hemisphere snow cover trend line for this year is starting to approach second lowest position:
Title: Re: The 2017 melting season
Post by: bbr2314 on April 01, 2017, 12:31:09 AM
Northern Hemisphere snow cover trend line for this year is starting to approach second lowest position:
Looks like data differs substantially; the Canadians are showing about average extent but possibly still record volume.

I think there are four key areas of anomalies at the moment; on the plus side, far NE Siberia and Quebec/the hinterlands of the Hudson are all glaringly snowy at the moment, with purples now appearing in parts of these regions.

On the flipside, the western areas of North America and Russia are dominated by reds (and in the former's case, even yellows). Eastern Siberia near Okhotsk also appears to be suffering deficits.

I would posit that this heralds a very brutal melt season for both the Pacific and Russian sides of the Arctic in general, but particularly Bering/Chuchki/Barentz/Kara.

(https://www.ccin.ca/home/sites/default/files/snow/snow_tracker/plot_anom_sdep.png)
Title: Re: The 2017 melting season
Post by: DrTskoul on April 01, 2017, 01:35:06 AM
That snow is going to melt pretty fast this year....dont see it lasting... and record volume was very warm ground due to insulation...
Title: Re: The 2017 melting season
Post by: bbr2314 on April 01, 2017, 01:48:11 AM
That snow is going to melt pretty fast this year....dont see it lasting... and record volume was very warm ground due to insulation...
i think record volume is due to increasingly open arctic ocean (i.e. record low sea ice volume directly translates into record high NHEM snowpack volume), though i agree that the warm ground insulation is going to be a factor across the permafrost areas that continue to warm/melt (mostly Siberia). this is not the case in Quebec though.

i think that we will definitely see a plunge in overall extent and may end up with record overall lows but on the flipside, the situation re: sea ice may favor extended cover vs. normal in NE Siberia and especially in Quebec. this is because as we see less ice in the Arctic and as it melts out earlier, the first-year ice in Hudson Bay is likelier to outlive the ice further to the N, which (IMO) is likely to favor persistent cold air over the relatively lower-latitude areas of SE/Central Canada.

will be very interesting to watch the evolution this melt season!
Title: Re: The 2017 melting season
Post by: TheUAoB on April 01, 2017, 02:13:44 AM
That snow is going to melt pretty fast this year....dont see it lasting... and record volume was very warm ground due to insulation...
i think record volume is due to increasingly open arctic ocean (i.e. record low sea ice volume directly translates into record high NHEM snowpack volume), though i agree that the warm ground insulation is going to be a factor across the permafrost areas that continue to warm/melt (mostly Siberia). this is not the case in Quebec though.

i think that we will definitely see a plunge in overall extent and may end up with record overall lows but on the flipside, the situation re: sea ice may favor extended cover vs. normal in NE Siberia and especially in Quebec. this is because as we see less ice in the Arctic and as it melts out earlier, the first-year ice in Hudson Bay is likelier to outlive the ice further to the N, which (IMO) is likely to favor persistent cold air over the relatively lower-latitude areas of SE/Central Canada.

will be very interesting to watch the evolution this melt season!
I'm afraid, I think you're grasping at straws.  Hudson is looking pretty thin and temperatures have been pretty high there recently.  Why do you think Quebec is exceptional when it comes to the ground insulation effect of snow cover?
Title: Re: The 2017 melting season
Post by: bbr2314 on April 01, 2017, 02:43:59 AM
That snow is going to melt pretty fast this year....dont see it lasting... and record volume was very warm ground due to insulation...
i think record volume is due to increasingly open arctic ocean (i.e. record low sea ice volume directly translates into record high NHEM snowpack volume), though i agree that the warm ground insulation is going to be a factor across the permafrost areas that continue to warm/melt (mostly Siberia). this is not the case in Quebec though.

i think that we will definitely see a plunge in overall extent and may end up with record overall lows but on the flipside, the situation re: sea ice may favor extended cover vs. normal in NE Siberia and especially in Quebec. this is because as we see less ice in the Arctic and as it melts out earlier, the first-year ice in Hudson Bay is likelier to outlive the ice further to the N, which (IMO) is likely to favor persistent cold air over the relatively lower-latitude areas of SE/Central Canada.

will be very interesting to watch the evolution this melt season!
I'm afraid, I think you're grasping at straws.  Hudson is looking pretty thin and temperatures have been pretty high there recently.  Why do you think Quebec is exceptional when it comes to the ground insulation effect of snow cover?

Hudson is relatively thin compared to the remnant multi-year ice but it is still thicker than almost the entirety of the Arctic Ocean. I think Quebec is exceptional because it is downwind of Greenland a large portion of the year, and combined with Hudson Bay, that leaves it as the region least vulnerable to warming in an AGW scenario (IMO).

Without permafrost, there is no damage underneath, either. In fact I am fairly sure Quebec has been persistently cooler than average at most times of year (but particularly summer) for the past few years, a glaring contrast to most other polar regions.
Title: Re: The 2017 melting season
Post by: romett1 on April 01, 2017, 08:47:12 AM
Bering Strait is also opening up as winds were from favourable direction (9 - 11 m/s).
So ice extent is same, but remaining ice pretty much wind-driven.
Images: Worldview, Mar 29 - Mar 31.
Title: Re: The 2017 melting season
Post by: romett1 on April 01, 2017, 09:35:35 AM
Latest GFS anomalies until next Saturday and 5-day forecast (Climate Reanalyzer).
Seems like starting from Wed we may see cooler temperatures across Arctic.
Still windy at Kara Sea, Barents Sea, Fram Strait and at Bering Strait.
Title: Re: The 2017 melting season
Post by: Neven on April 01, 2017, 10:21:37 AM
The ice south of Novaya Zemlya is pushing back now:
Title: Re: The 2017 melting season
Post by: subgeometer on April 01, 2017, 12:32:30 PM
That snow is going to melt pretty fast this year....dont see it lasting... and record volume was very warm ground due to insulation...

GFS is showing substantial snowmelt in the MacKenzie and Ob catchments over the next week
Title: Re: The 2017 melting season
Post by: meddoc on April 01, 2017, 12:39:51 PM
The ice south of Novaya Zemlya is pushing back now:

That's just the icecap exting the Fram and beyond.
Title: Re: The 2017 melting season
Post by: iceman on April 01, 2017, 04:57:52 PM
The ice south of Novaya Zemlya is pushing back now:

That's just the icecap exting the Fram and beyond.
You're two seas and one strait off.
    The expansion in Barents looks impressive on the animation - and is likely to continue another couple days - but isn't so unusual for this time of year.
    Still too early to tell whether Kara will refreeze completely, but doesn't seem to be in the cards and for the coming week.
Title: Re: The 2017 melting season
Post by: Jim Hunt on April 01, 2017, 05:27:27 PM
Ice mass balance buoy 2017A isn't updating daily like in the good old days. This is the latest available info:

http://GreatWhiteCon.info/resources/ice-mass-balance-buoys/winter-201617-imb-buoys/#2017A (http://GreatWhiteCon.info/resources/ice-mass-balance-buoys/winter-201617-imb-buoys/#2017A)

Current Buoy Data (03/27/2017):

Pos: 72.81 N, 146.57 W
Air Temp: -26.78 C
Air Pres: 1019.21 mb
Snow depth : 10 cm
Ice thickness : 96 cm

Since Deployment (03/09/2017)
Snow surface accumulation: 10 cm
Ice bottom growth : 11 cm
Title: Re: The 2017 melting season
Post by: Tigertown on April 01, 2017, 05:49:04 PM
I think "pushing" to be a good choice of wording for this side of the Arctic. Navy HYCOM shows an increase in drift, which no doubt pushed the ice in this direction faster than it could melt. You can see a shift throughout the pack in concentration toward this side. So it is definitely not to be confused with growth or refreezing.
CLICK IMAGE      25th vs. 31st    (side by side below)
(http://)
Title: Re: The 2017 melting season
Post by: Random_Weather on April 01, 2017, 06:27:40 PM
@ all GFS-Fans

Some point to make:

At the momentan (or since March), GFS is strong cool biased in forecast (means it go a lot warmer then GFS has forecast in +168h) you can check this out here: http://www.karstenhaustein.com/climate.php (http://www.karstenhaustein.com/climate.php) so personally i do prefer ECMWF which is much better in mid range forecast. The other thing is a potential Snow-Cover-Forecast-Bias during Spring, GFS overeastimate snow melt, i think (since i observe it) its an issue with inversion weather on ground, if you want to see it on your on, see here: http://www.instantweathermaps.com/GFS-php/showmap-nh.php?run=2015030706&var=SNOD_sfc&hour=384 (http://www.instantweathermaps.com/GFS-php/showmap-nh.php?run=2015030706&var=SNOD_sfc&hour=384)

In some words:
06z analysis GFS from first april shows 17.81% Snow Cover of the NH
60h ago, GFS forcast 17.19% for this date, this is a bias to 1.60 Mio km^2

Its a huge bias on a short forecast time. So GFS-Snow-Forecast should be used with caution
Title: Re: The 2017 melting season
Post by: Shared Humanity on April 01, 2017, 09:01:54 PM
Ice mass balance buoy 2017A isn't updating daily like in the good old days. This is the latest available info:

[url]http://GreatWhiteCon.info/resources/ice-mass-balance-buoys/winter-201617-imb-buoys/#2017A[/url] ([url]http://GreatWhiteCon.info/resources/ice-mass-balance-buoys/winter-201617-imb-buoys/#2017A[/url])

Current Buoy Data (03/27/2017):

Pos: 72.81 N, 146.57 W
Air Temp: -26.78 C
Air Pres: 1019.21 mb
Snow depth : 10 cm
Ice thickness : 96 cm

Since Deployment (03/09/2017)
Snow surface accumulation: 10 cm
Ice bottom growth : 11 cm


1 meter thick ice...that makes me nervous. The Beaufort is going to open up early this year as well.
Title: Re: The 2017 melting season
Post by: DrTskoul on April 01, 2017, 09:10:00 PM
Ice mass balance buoy 2017A isn't updating daily like in the good old days. This is the latest available info:

[url]http://GreatWhiteCon.info/resources/ice-mass-balance-buoys/winter-201617-imb-buoys/#2017A[/url] ([url]http://GreatWhiteCon.info/resources/ice-mass-balance-buoys/winter-201617-imb-buoys/#2017A[/url])

Current Buoy Data (03/27/2017):

Pos: 72.81 N, 146.57 W
Air Temp: -26.78 C
Air Pres: 1019.21 mb
Snow depth : 10 cm
Ice thickness : 96 cm

Since Deployment (03/09/2017)
Snow surface accumulation: 10 cm
Ice bottom growth : 11 cm


1 meter thick ice...that makes me nervous. The Beaufort is going to open up early this year as well.


 The exact thickness depends on the selection criteria of the scientists that installed it.  However the thickening rate is more worrisome. 
Title: Re: The 2017 melting season
Post by: VeliAlbertKallio on April 01, 2017, 09:13:17 PM
I am feeling particularly awkward about the South-East moving blob of ice from the Baffin Bay on Tigertown's HYCOM link. There isn't much left behind on northern Baffin Bay except a thin frost veneer and few leftover pieces. This already seems clearing the plug from the mouth of North West passage and Nares strait. Expect early ice losses in the Canadian Archipelago looks like a domino effect progressing there from the Baffin Bay.
Also, on HYCOM.
(http://)
Title: Re: The 2017 melting season
Post by: Shared Humanity on April 01, 2017, 09:38:06 PM
I am feeling particularly awkward about the South-East moving blob of ice from the Baffin Bay on Tigertown's HYCOM link. There isn't much left behind on northern Baffin Bay except a thin frost veneer and few leftover pieces. This already seems clearing the plug from the mouth of North West passage and Nares strait. Expect early ice losses in the Canadian Archipelago looks like a domino effect progressing there from the Baffin Bay.
Also, on HYCOM.
(http://)

The only way the Northwest passage is not navigable this year is if an active garlic press sends MYI through the CAA into the passage in large quantities.
Title: Re: The 2017 Melting Season
Post by: magnamentis on April 01, 2017, 11:15:24 PM
Just in time LOL, the high was at around 1.6 Celsius / 36F

( and there is still water to see for weeks now and most of the time it was much more open water than right now )



What does the web cam in Barrow look like now?


quite regular conditions for the time of the year :-)

you find the links on top right corner under "webcams"

http://seaice.alaska.edu/gi/observatories/barrow_webcam (http://seaice.alaska.edu/gi/observatories/barrow_webcam)
Title: Re: The 2017 melting season
Post by: subgeometer on April 02, 2017, 12:57:09 AM
I think "pushing" to be a good choice of wording for this side of the Arctic. Navy HYCOM shows an increase in drift, which no doubt pushed the ice in this direction faster than it could melt. You can see a shift throughout the pack in concentration toward this side. So it is definitely not to be confused with growth or refreezing.
CLICK IMAGE      25th vs. 31st    (side by side below)
(http://)

The ice is pushed out rapidly between FJL(at top) and Svalbard on this Worldview animation of March 19-april1 - the expanse of open water behind FJL grows 100km in a matter of days

The second attachment is a larger version of the same images which better show the state of the ice - the floes are like flat pebbles, corners ground off and of all sizes

Title: Re: The 2017 melting season
Post by: Tigertown on April 02, 2017, 05:57:14 AM
It might be a good time to check back in on Baffin Bay.
(http://)
Title: Re: The 2017 melting season
Post by: romett1 on April 02, 2017, 08:08:50 AM
Some export through Bering Strait Mar 30 - Apr 01. According to Earth-nullschool there are stronger winds (12 - 14 m/s) again starting Wed-Thu, pushing more ice to Bering Sea. Images: Worldview.
Title: Re: The 2017 melting season
Post by: romett1 on April 02, 2017, 09:41:13 AM
Latest GFS anomalies until next Sunday and 5-day forecast (Climate Reanalyzer). Second half of the week still colder (or not so warm as first half of the week).
Title: Re: The 2017 melting season
Post by: oren on April 02, 2017, 10:30:47 AM
subgeometer, your animation is scary. So much ice pushed out while extent is stationary, the CAB is gutted from the inside with the melting season barely started.
Title: Re: The 2017 melting season
Post by: slow wing on April 02, 2017, 12:58:31 PM
Arctic Sea Ice Currently Taking a Hit From All Sides
Yes, the Arctic sea ice seems to be taking a hit from all 4 sides of the Arctic Basin at the beginning of the melt season.

Summarising recent posts above:
1) Russian side - big cracks and areas of low concentration as the ice is blown out to sea
2) Atlantic side - ice blown out into the Barents sea, where bottom melt might be expected
3) Ice transport through the Nares Strait seems to be setting up
4) Ice is being blown out through the Bering Strait and the ice already South of there is breaking up and being blown further South.


U. Bremen Ice Concentration Map Year-on-Year Comparison for 1 April
April 1st is one of the chosen days for Neven's useful year-to-year comparison of the U. Bremen Arctic sea ice concentration maps (https://sites.google.com/site/arcticseaicegraphs/concentration-maps/sic0401).

As attached below, this comparison shows the ice this year on the Russian side - i.e. the ESS and Laptev Sea (red arrow) to be, on the face of it, in the worst state for this date of any of the illustrated years.


CPOM/ESA Spring Ice Thickness Maps for 2011-14 and 2017
The CPOM/ESA measurements of ice thickness are wrapping up for the end of this freeze season. As they are actual measurements - albeit with corrections - rather than more model-based assessments, I tend to consider that they probably give the most accurate picture of the ice thickness distribution over the Arctic Basin. Also attached then is a gif showing their latest 28-day map compared against the years for which they publish well-calibrated Spring maps, namely 2011-14.

  From these maps, the 2013 Arctic sea is seen to have been in terrible condition after the carnage of the record 2012 melt season. On the face of it, 2013 had less thick ice around this date than even this year, in contrast to the other years shown having considerably more ice than this year.

   And yet 2013 turned out to be a recovery year for the sea ice, which suggests that this year also has that potential in the case that this year's upcoming melt season turns out to be mild. On the other hand, is this year's ice already being blown around more than was the case in 2013?

   The bottom line from this comparison is that a mild melt season this year could still lead to a recovery in the Arctic sea ice but, on the other hand, a historic low minimum extent in 2017 is looking quite likely. It's early days yet.
Title: Re: The 2017 melting season
Post by: seaicesailor on April 02, 2017, 02:34:59 PM
Arctic Sea Ice Currently Taking a Hit From All Sides
Yes and the hit suggested below ...

Latest forecast runs suggests more high pressure dominated weather in the foreseeable future. If easterlies over Canadian Arctic will emerge we might get an early opening of the Beaufort Sea. ...


seems really certain now, just as we enter April. Added latest ECMWF forecast from hour 0 to 144.
Title: Re: The 2017 melting season
Post by: Jim Hunt on April 02, 2017, 03:06:04 PM
Arctic Sea Ice Currently Taking a Hit From All Sides


My own analysis of the current situation, especially for the benefit of Rep. Lamar Smith (https://twitter.com/GreatWhiteCon/status/848496265734365184)!

Facts About the Arctic in April 2017 (http://greatwhitecon.info/2017/04/facts-about-the-arctic-in-april-2017/)

Some extra graphs to add to the collection. All in all, the prognosis is not good. Both in Washington DC and much further north.
Title: Re: The 2017 melting season
Post by: seaicesailor on April 02, 2017, 03:16:15 PM
The Beaufort sea ice cracks that appeared in March 29. The area seen before and after using AMSR2 sea ice brightness temperature, the animation runs from March 16 and everything has been very quiet, except strong sea ice drift that happened only for one or two days. The microwave image reveals neatly the weakened remain of the crack, will see what happens with it during April.
Title: Re: The 2017 melting season
Post by: Shared Humanity on April 02, 2017, 04:45:58 PM
subgeometer, your animation is scary. So much ice pushwd out while extent is stationary, the CAB is gutted from the inside with the melting season barely started.


A new and permanent feature of the Arctic sea ice is mobility. The ice is increasingly mobile and vulnerable to mechanical forces (mixing etc.) than when it was a relatively solid patch of thick MYI. We can see this increasing mobility year round with these wonderful animations posted here.  We can measure it if we look at a 40 year trend in ice dispersion at minimum.
Title: Re: The 2017 melting season
Post by: Tigertown on April 02, 2017, 08:33:15 PM
The ice between FJL and Svalbard looks to continue onward and break off from the main pack and make a happy little trip deep into the Barents. If it only knew.
(http://)
Title: Re: The 2017 melting season
Post by: jdallen on April 03, 2017, 04:31:45 AM
Year over year 2016 vs 2017 comparison of ice temps in the Hudson/Baffin and environs.

2017 pretty clearly has a lot more available heat sooner than 2016.  Entirely subjectively, the quality of the ice using visible light suggests to me the Hudson is 1-2 weeks ahead of (last years) schedule, in spite of low late season temperatures.

Palette is Sea Ice brightness temperatures 6KM 89V using the "rainbow" palette squashed to 182-277K

EOSDIS Worldview basic link: https://worldview.earthdata.nasa.gov
Title: Re: The 2017 melting season
Post by: jdallen on April 03, 2017, 06:27:22 AM
IJIS has extent running in place.  It would appear dispersion is taking place.

Generated this quick animation from worldview using 12KM Sea ice concentration.  It doesn't give a lot of detail, but does demonstrate how the ice is spreading out - which unfortunately in the Barentsz means into rather warm water.

<click to animate>
Title: Re: The 2017 melting season
Post by: Tigertown on April 03, 2017, 06:46:26 AM
@jdallen
Likewise it seems in the Bering Sea. Dispersion and melting.
Title: Re: The 2017 melting season
Post by: romett1 on April 03, 2017, 09:27:16 AM
Latest GFS anomalies until next Monday and 5-day forecast (Climate Reanalyzer). Definitely colder over mainland Siberia, but relatively warm over Beaufort Sea (high pressure). Strong winds over Barents Sea and Kara Sea Apr 7 - Apr 10. Locally also strong winds over Beaufort Apr 5 - Apr 10.
Title: Re: The 2017 melting season
Post by: Cid_Yama on April 03, 2017, 10:36:22 AM
You can see the vulnerability.  20 cm is less than a foot.  Heck, 30 cm is a foot.

(https://seaice.uni-bremen.de/data/smos/curent_SIT.png)
Title: Re: The 2017 melting season
Post by: Iain on April 03, 2017, 01:53:19 PM
Are the purple and mauve areas inside the 85 deg latitude, indicating 400 – 500 mm of thickness for real?

Or are they a false reading at the edge of the scan for some reason?
Title: Re: The 2017 melting season
Post by: Archimid on April 03, 2017, 02:06:11 PM
Definitely colder .

First,  thanks romett1 for this helpful update. I find it very useful.

 A nit pick if I may. It is not necesarilly colder, only less anomalously warm.  The Arctic is just as  warm as it was in the middle of winter, but the mean temperatures are catching up this year's temperatures. Now that we approach the transition time from a winter arctic to a summer arctic, temperature anomalies are likely to be much closer to the mean.  Once the temperatures reach equilibrium with the ice, the temperature anomalies are also likely to stay close to the mean. At least while there is enough ice. If sufficient ice is lost then the anomalies will jump up significantly.
Title: Re: The 2017 melting season
Post by: Tigertown on April 03, 2017, 02:40:10 PM
Are the purple and mauve areas inside the 85 deg latitude, indicating 400 – 500 mm of thickness for real?

Or are they a false reading at the edge of the scan for some reason?
From what I have heard SMOS is supposed to be extremely accurate up to 0.5 meters, but that does look weird.
Title: Re: The 2017 melting season
Post by: DrTskoul on April 03, 2017, 03:03:01 PM
Are the purple and mauve areas inside the 85 deg latitude, indicating 400 – 500 mm of thickness for real?

Or are they a false reading at the edge of the scan for some reason?
From what I have heard SMOS is supposed to be extremely accurate up to 0.5 meters, but that does look weird.

They have been there all winter.  I believe the are artifacts of the North Pole hole ( sampling and interpolation errors ).

Title: Re: The 2017 melting season
Post by: romett1 on April 03, 2017, 03:05:29 PM
Definitely colder .

First,  thanks romett1 for this helpful update. I find it very useful.

 A nit pick if I may. It is not necesarilly colder, only less anomalously warm.  The Arctic is just as  warm as it was in the middle of winter, but the mean temperatures are catching up this year's temperatures.

Thanks. I'm thinking the same (less anomalously warm and mean temperatures are rising). I checked that GFS anomaly maps for Arctic mean 65°N - 90°N. So it includes land north of 65° as well. When it's colder than usual over northern part of Russia, Canada or Greenland, it brings the average down.
Title: Re: The 2017 melting season
Post by: Jim Williams on April 03, 2017, 03:32:45 PM
Definitely colder .

First,  thanks romett1 for this helpful update. I find it very useful.

 A nit pick if I may. It is not necesarilly colder, only less anomalously warm.  The Arctic is just as  warm as it was in the middle of winter, but the mean temperatures are catching up this year's temperatures.

Thanks. I'm thinking the same (less anomalously warm and mean temperatures are rising). I checked that GFS anomaly maps for Arctic mean 65°N - 90°N. So it includes land north of 65° as well. When it's colder than usual over northern part of Russia, Canada or Greenland, it brings the average down.
Since I am waiting for the year summer temps spike significantly above the mean I agree with this analysis.  Whenever that happens you can say that the Arctic is effectively ice free.  I doubt it will be this year, but you never know.
Title: Re: The 2017 melting season
Post by: JimboOmega on April 03, 2017, 08:31:49 PM
BTW the thread to take the year-round ice free arctic discussion is this one: http://forum.arctic-sea-ice.net/index.php/topic,191.msg102977.html#msg102977 (http://forum.arctic-sea-ice.net/index.php/topic,191.msg102977.html#msg102977)

What I really want to know about this year is... when do we see the impact of this low volume situation? Last year we heard "rubble", "weak", "low volume", "melt ponds"... all the time, and didn't see the extent impacts I would have felt from such talk.
Title: Re: The 2017 melting season
Post by: wili on April 03, 2017, 08:50:45 PM
JO, what "extent impacts" were you expecting?

Ice that is "rubble"--something like a slushy--is going to be able to spread out faster and further more easily than an ice pack that is mostly made up of solid, multi-meter-thick ice slabs, right?

I suspect that most of our metrics are no longer measuring exactly what they used to be...we can get solid figures on various supposed measures of quantity more easily than we can get reliable estimates of overall quality of the ice.
Title: Re: The 2017 melting season
Post by: JimboOmega on April 03, 2017, 09:07:34 PM
JO, what "extent impacts" were you expecting?

Ice that is "rubble"--something like a slushy--is going to be able to spread out faster and further more easily than an ice pack that is mostly made up of solid, multi-meter-thick ice slabs, right?

I suspect that most of our metrics are no longer measuring exactly what they used to be...we can get solid figures on various supposed measures of quantity more easily than we can get reliable estimates of overall quality of the ice.

Last year, I was expecting thin, spread out ice to... well, melt.

But rather than get into an argument about what the "Real state" of the ice is that our metrics can't measure... what I'd like to know is what people expect of the things our metrics can measure.

If we take it as given that the ice is much less thick than last year, that all the good ice went out the Fram, etc, what do we expect that to mean for the ice in June? As measured by ASMR2 or NSDIC or JAXA or your favorite measure.

Will we see a rapid cliff once some condition is met because the ice is too thin to resist? Or will we have a new-normal (2010s)ish melting season but... feel like it's thinner the entire time?  I understand that the weather matters and would be happy with someone saying something like "It's more likely we'll have a record low extent than we did with the same extent last year, because this year's ice is thinner".
Title: Re: The 2017 melting season
Post by: Jim Williams on April 03, 2017, 09:22:10 PM
JO, what "extent impacts" were you expecting?

Ice that is "rubble"--something like a slushy--is going to be able to spread out faster and further more easily than an ice pack that is mostly made up of solid, multi-meter-thick ice slabs, right?

I suspect that most of our metrics are no longer measuring exactly what they used to be...we can get solid figures on various supposed measures of quantity more easily than we can get reliable estimates of overall quality of the ice.

Last year, I was expecting thin, spread out ice to... well, melt.

But rather than get into an argument about what the "Real state" of the ice is that our metrics can't measure... what I'd like to know is what people expect of the things our metrics can measure.

If we take it as given that the ice is much less thick than last year, that all the good ice went out the Fram, etc, what do we expect that to mean for the ice in June? As measured by ASMR2 or NSDIC or JAXA or your favorite measure.

Will we see a rapid cliff once some condition is met because the ice is too thin to resist? Or will we have a new-normal (2010s)ish melting season but... feel like it's thinner the entire time?  I understand that the weather matters and would be happy with someone saying something like "It's more likely we'll have a record low extent than we did with the same extent last year, because this year's ice is thinner".
JO, it's fun to guess, and it's fun to come up with every scrap of information we can find on the subject, but when it comes right down to it I don't think anyone has a clue what is going to actually happen.
Title: Re: The 2017 melting season
Post by: jdallen on April 03, 2017, 09:28:37 PM
JO, what "extent impacts" were you expecting?
<snippage>
<more snippage>
Will we see a rapid cliff once some condition is met because the ice is too thin to resist?
<and even more snippage>
I expect a cliff in 2-3 weeks as effective received insolation pushes past an average effective level of 3 KWH/Day/M2 at 85N and below. (Incident is already much higher). When that happens, the Barentsz, the Bering, the Kara, the Okhotsk and parts of Baffin and Hudson's bays will see dramatic melt backs.  We could see a solid week of century drops.
Title: Re: The 2017 melting season
Post by: Tigertown on April 03, 2017, 09:34:31 PM
In addition to being  more susceptible to melt, the ice has less protection against export.
If it can flow this freely now, what about a month from now? Or two, three months from now?
(http://)
Title: Re: The 2017 melting season
Post by: jdallen on April 03, 2017, 10:02:26 PM
In addition to being  more susceptible to melt, the ice has less protection against export.
If it can flow this freely now, what about a month from now? Or two, three months from now?
I actually somewhat expect export to support extent - cause it to "run in place" - but reduce concentration.  I think the effects of export *now* will be more aparent *later* in the season, as in after June.
Title: Re: The 2017 melting season
Post by: misfratz on April 03, 2017, 10:31:55 PM
Last year, I was expecting thin, spread out ice to... well, melt.
...
I understand that the weather matters and would be happy with someone saying something like "It's more likely we'll have a record low extent than we did with the same extent last year, because this year's ice is thinner".
One winter morning, many years ago, I brought a chunk of ice that had frozen in a pot outside into the kitchen, and I had my mother, my daughter and I all guess how long it would take to melt entirely. I forget the details, but what I do remember is that it took a lot longer than we expected to completely melt out.

So, while the changes in the Arctic are rapid in the context of Arctic Sea Ice, I think we all underestimate how hard it is to melt the vast quantity of sea ice that currently exists.

So, yes, a lot is down to the weather, and the weather last year was not conducive to ice melt, but we weren't that far off a record regardless. When we have a year like 2007, or 2012, then we will have another monster record.
Title: Re: The 2017 melting season
Post by: Buddy on April 03, 2017, 11:15:12 PM
When we have a year like 2007, or 2012, then we will have another monster record.

2007 + 5 = 2012

2012 + 5 = 2017

Makes a guy go hmmmmmmmmmmmmm
Title: Re: The 2017 melting season
Post by: Neven on April 03, 2017, 11:16:32 PM
The ice keeps pushing back against the open water southwest of Novaya Zemlya. Given the wind forecast I think it's going to ice over again, so no super-unprecedented on that score. But we'll have to see what happens after that (that region only opened after the first week of May for years like 2011 and 2012).
Title: Re: The 2017 melting season
Post by: pauldry600 on April 04, 2017, 12:21:07 AM
I wouldnt really expect a huge record this year.

Maybe we will beat the old record or get down to about 3.7m that would be my guess.
Title: Re: The 2017 melting season
Post by: oren on April 04, 2017, 12:36:49 AM
JimboOmega, this year is already objectively different from all other recent years by its winter PIOMAS results. I hope you call this a measurement even though it's mostly a model.
I expect 2017 to reach:
Record low volume with very high probability.
Record low area with high probability.
Record low JAXA extent with 50-50 probability.
Yes the weather can do all sorts of wonders, but at some point it's just average weather that brings the record.
Title: Re: The 2017 melting season
Post by: subgeometer on April 04, 2017, 12:53:18 AM
Are the purple and mauve areas inside the 85 deg latitude, indicating 400 – 500 mm of thickness for real?

Or are they a false reading at the edge of the scan for some reason?

I think the spots around the pole hole are noise, there's generally a random spattering there
Title: Re: The 2017 melting season
Post by: cesium62 on April 04, 2017, 01:46:28 AM
I wouldnt really expect a huge record this year.

Maybe we will beat the old record or get down to about 3.7m that would be my guess.

Why?
Title: Re: The 2017 melting season
Post by: cesium62 on April 04, 2017, 02:04:47 AM
JimboOmega, this year is already objectively different from all other recent years by its winter PIOMAS results. I hope you call this a measurement even though it's mostly a model.
I expect 2017 to reach:
Record low volume with very high probability.
Record low area with high probability.
Record low JAXA extent with 50-50 probability.
Yes the weather can do all sorts of wonders, but at some point it's just average weather that brings the record.

To my mind:
2015 had a big thick chunk of ice in the Beaufort, and warm El Nino weather.

In 2016, the less thick chunk of ice had migrated to the ESS and Laptev, there was still warm El Nino weather, and a strong August storm dispersed a lot of ice to the South.

In 2017, the thick chunks of ice are gone, the El Nino weather is gone, and it seems like there's a 20% to 25% chance of a strong August storm.

I think the El Nino warmth had an effect on the Pacific side, but not much effect elsewhere.  So I'll guess that the minimum extent will probably be near the 2007, 2015, 2016 minimums, with a 20% to 25% chance of a strong August storm setting a new record.

I wonder if dispersal of ice to the South in early April would tend to cool off the southern oceans while leaving time for the CAB to rethicken?
Title: Re: The 2017 melting season
Post by: jdallen on April 04, 2017, 03:29:22 AM
The ice keeps pushing back against the open water southwest of Novaya Zemlya. Given the wind forecast I think it's going to ice over again, so no super-unprecedented on that score. But we'll have to see what happens after that (that region only opened after the first week of May for years like 2011 and 2012).
Nice having sunlight back to see what's actually going on.

Same time frame in Worldview suggests dispersion to me rather than any sort of freezing.

<click to animate>
Title: Re: The 2017 melting season
Post by: jdallen on April 04, 2017, 03:51:30 AM
Using aqua-modis band-31 day, here's what I call "March to the Exit" - MYI passing out the Fram and Victoria strait into the Barentsz and Greenland seas to its doom.
Title: Re: The 2017 melting season
Post by: jdallen on April 04, 2017, 04:07:08 AM
Last but not least, some detail using Aqua Modis bands 7-2-1 that shows just exactly what happens when that ice reaches the "scorching" Atlantic heat influx we've been watching for the last 2 years.
Title: Re: The 2017 melting season
Post by: romett1 on April 04, 2017, 09:35:09 AM
Latest GFS anomalies until next Tuesday and 5-day forecast (Climate Reanalyzer). Currently showing heat is starting to return next week - Chukchi, Bering, Beaufort, Barents and Kara seas warmer than usual. Next week colder over ESS, Siberia mainland and Canadian Arctic Archipelago.
Title: Re: The 2017 melting season
Post by: pauldry600 on April 04, 2017, 11:09:56 AM
Grated cheese yesterday for a sandwich

However I squashed some in my hand and all back together again.

I think this dispersion is like that and will mean a slow start to 2017 melt season

It may actually help the ice short term but long term (in a few years) it will be gone,
Title: Re: The 2017 melting season
Post by: Jim Hunt on April 04, 2017, 11:15:23 AM
According to IMB buoy 2017A it's now sitting on ice over 1 meter thick:

http://GreatWhiteCon.info/2017/04/facts-about-the-arctic-in-april-2017/#comment-221215 (http://GreatWhiteCon.info/2017/04/facts-about-the-arctic-in-april-2017/#comment-221215)

Current Buoy Data (04/03/2017):

Pos: 72.90 N, 147.10 W
Air Temp: -25.88 C
Air Pres: 1021.52 mb
Snow depth : 9 cm
Ice thickness : 102 cm

Since Deployment (03/09/2017)

Snow surface accumulation: 9 cm
Ice bottom growth : 17 cm
Title: Re: The 2017 melting season
Post by: seaicesailor on April 04, 2017, 11:39:55 AM
Last but not least, some detail using Aqua Modis bands 7-2-1 that shows just exactly what happens when that ice reaches the "scorching" Atlantic heat influx we've been watching for the last 2 years.
I am not sure this ice can last for the summer...
Title: Re: The 2017 melting season
Post by: stjuuv on April 04, 2017, 11:59:38 AM
One winter morning, many years ago, I brought a chunk of ice that had frozen in a pot outside into the kitchen, and I had my mother, my daughter and I all guess how long it would take to melt entirely. I forget the details, but what I do remember is that it took a lot longer than we expected to completely melt out.

So, while the changes in the Arctic are rapid in the context of Arctic Sea Ice, I think we all underestimate how hard it is to melt the vast quantity of sea ice that currently exists.
You should retry your experiment so that you don't keep the ice in the pot where it was frozen, but rather put it to float in a bathtub full of water a few degrees warmer than freezing, and keep the ice and water slightly in motion as well. That way you should find that the ice will melt a lot faster, as can be seen in the satellite images above.
Title: Re: The 2017 melting season
Post by: Neven on April 04, 2017, 12:57:19 PM
The ice keeps pushing back against the open water southwest of Novaya Zemlya. Given the wind forecast I think it's going to ice over again, so no super-unprecedented on that score. But we'll have to see what happens after that (that region only opened after the first week of May for years like 2011 and 2012).
Nice having sunlight back to see what's actually going on.

Same time frame in Worldview suggests dispersion to me rather than any sort of freezing.

It's a combination of dispersion, winds pushing the ice back to where it came from, and then leads freezing over with a very thin layer of ice. Here, I'm interested in the visual power of the satellite image of open water at such an unprecedented early time in the Kara Sea. It doesn't look like that if even a veneer of ice is covering the area.

But that doesn't mean all is dandy in the Kara.
Title: Re: The 2017 melting season
Post by: Bill Fothergill on April 04, 2017, 01:48:47 PM
Pardon the pun, but watching the ease of ice transport in some of the preceding animations is truly chilling. Whilst there are still Freezing Degree Days getting clocked up in the High Arctic, it does seem a case of "too little, too late".

The fact that, purely in terms of extent, the 2017 melt season appears to have somewhat stalled at the moment, simply serves as a reminder of what transpired during 2012. If one ranks the March, April and May NSIDC monthly averages, 2012 currently occupies 14th, 20th and 13th lowest positions respectively. However, the horror show only really began in June of that year. Given that the present extent is nearly 1 million sq kms lower than that recorded for the equivalent date in 2012 should certainly give cause for apprehension.

One of the (many) ways of graphically illustrating what has been happening to Arctic sea ice is to display the number of days in each year that either has been, or indeed still is, amongst the lowest three recorded for the date.

Possibly the best example - certainly the best I can think of - is to show how 2007 has fared. According to the inhabitants of flat-land, that year was supposed to represent the nadir for Arctic sea ice. A major strand of the "logic" - and I use that word very advisedly - behind this hypothesis, was that the September minimum had increased in each of the two following years. Using NSIDC average monthly values, the September figures for Arctic sea ice extent were...

2007 = 4.32 millions sq kms
2008 = 4.73 millions sq kms
2009 = 5.39 millions sq kms

So, there is no arguing with the fact that 2009 > 2008 > 2007. The format of that inequality, allied with the fact that there had been anomalously high temperatures recorded in the Arctic during the 40's, had been used to peddle the myth that 2008 and 2009 heralded the fact that the turning point had been passed in an ~ 60 year cycle. This immediately gained uncritical acceptance in flat-land, as the average climate change sceptic wouldn't know what genuine scepticism was if it jumped up and bit them on the arse.

However, the following inequalities between NSIDC average September extents somehow seemed to have been overlooked...

1983 > 1982 > 1981
1992 > 1991 > 1990
2001 > 2000 > 1999

(Incidentally, the increase between 1990 and 1992 was quarter of a million sq kms greater than the much-vaunted 2007 - 2009 "recovery".)

{Of course, things have moved on since them, and their current meme is that the Arctic was effectively ice free nearly 100 years ago. There were so many obvious flaws in the original 60-year cycle meme, that even committee members in the House and the Senate would have had trouble keeping a straight face.}

Anyway, getting back to 2007, according to the JAXA/IJIS/ADS database, by the 31st December that year, it had registered the following daily figures...

153 days were lowest for that date
104 days were second lowest, and
105 days were third lowest. (That adds up to 362, and the other 3 days were 4th lowest.)

However, as at today, the equivalent numbers for 2007 read as follows...

Lowest: 4 days
2nd lowest: 70 days
3rd lowest: 46 days

The demise of 2007 from its position of preeminence can be seen in the attached chart. The first column shows how 2007 stood at year-end, and the subsequent columns show the decline at the end of each of the following years. The final column tracks in near-real-time as 2017 data arrives. So far this year, there have only been 8 "lowest 3" instances remaining from 2007. Each of them has been surpassed in 2017, with 2 dropping to 3rd lowest, and a further 6 dropping to 4th. As the 2017 melt season gets into gear, it will be "interesting" to see how much further 2007 will sink.


As we frequently say in Glasgow...

sic transit gloria mundi
 
Title: Re: The 2017 melting season
Post by: iceman on April 04, 2017, 01:55:44 PM
JO, what "extent impacts" were you expecting?
<snippage>
<more snippage>
Will we see a rapid cliff once some condition is met because the ice is too thin to resist?
<and even more snippage>
I expect a cliff in 2-3 weeks as effective received insolation pushes past an average effective level of 3 KWH/Day/M2 at 85N and below. (Incident is already much higher). When that happens, the Barentsz, the Bering, the Kara, the Okhotsk and parts of Baffin and Hudson's bays will see dramatic melt backs.  We could see a solid week of century drops.

Plausible but not the most likely scenario, I think.  Area/extent anomalies are already quite low in some regions - Bering and especially Okhotsk - that typically contribute to a rapid decline during April.
Title: Re: The 2017 melting season
Post by: gerontocrat on April 04, 2017, 03:05:57 PM
What melting season?

Sea ice extent at highest since March 17.
Sea ice volume (jaxa-amsr2-volume.png) going through the roof - nearly 2,000 km3 - in the last week.

Back to Nostradamus for inspiration?
Title: Re: The 2017 melting season
Post by: Tigertown on April 04, 2017, 03:07:11 PM
The way the ice is getting dispersed and spread out, it is just being set up for the drop. It is getting very close to time for insolation to start really going to work. The current extent numbers do not reflect the season ahead. The crash is on the way.

P.S. Here is what is keeping the extent up. jd has covered the Barents quite adequately and how the same scenario is playing out there. Neither side can hold out perpetually.
(http://)
Title: Re: The 2017 melting season
Post by: Jim Williams on April 04, 2017, 04:28:39 PM
What melting season?

Sea ice extent at highest since March 17.
Sea ice volume (jaxa-amsr2-volume.png) going through the roof - nearly 2,000 km3 - in the last week.

Back to Nostradamus for inspiration?

That is so great to hear. We have dodged a bullet, and need to fix our pollution now. A second chance.
On the other hand ... it's not true volume is through the roof.
And sea-ice extent is the lowest on record for this date.
Back to the Wizard of Oz for inspiration?
I'd vote Neverending Story for inspiration.
Title: Re: The 2017 melting season
Post by: VeliAlbertKallio on April 04, 2017, 06:57:19 PM
Pardon the pun, but watching the ease of ice transport in some of the preceding animations is truly chilling. Whilst there are still Freezing Degree Days getting clocked up in the High Arctic, it does seem a case of "too little, too late".

One of the (many) ways of graphically illustrating what has been happening to Arctic sea ice is to display the number of days in each year that either has been, or indeed still is, amongst the lowest three recorded for the date. Possibly the best example - certainly the best I can think of - is to show how 2007 has fared. ... ... The demise of 2007 from its position of preeminence can be seen in the attached chart. The first column shows how 2007 stood at year-end, and the subsequent columns show the decline at the end of each of the following years.  ..." [QUOTE ENDS]

>>

It would be interesting to seem similar graph using 2012 as the base year, since it would produce much larger red columns of the firsts... For the red-colour-pole-post, a major change occurred in 2012 and that would give us a slightly different 5-year (short climate period standing) with more prominent comparisons to the red (the previous worsts)... Anyone able to get hands on that?

I used the Defense Meteorological Satellite Program (DMSP) F-17 satellite readings to develop a different kind of graph: the-melting-days-remaining where the difference in sea ice area reduction from one day to the next was deducted. The remaining sea ice area during the latter date was then divided by that calculated difference figure of melting (sea ice area lost between the two days) to obtain the number of days melting would continue at that point (in an ideal, linear world of melting) for all that remaining sea ice to melt away completely.

There were times when F-17 reduction rate was sufficient to finish the job before end of summer, or September. In latter years this grew shorter. It was a somewhat arcane identifier how likely the sea ice was to melt away, but good enough to do statistical comparisons on-year-on year basis on sea ice area (= my industrial secret in sea ice area forecasting). 

This model with F-17 data did not account for decreasing insolation (like reducing insolation and temperature towards the end of summer). However were a total melt likely to occur the days remaining would continue to shrink steadily the longer. But then this F-17 satellite Trumped and I don't know if there is F-18 broadcasting anything else but the Republican propaganda nowadays...
Title: Re: The 2017 melting season
Post by: Bill Fothergill on April 04, 2017, 08:38:08 PM
It would be interesting to seem similar graph using 2012 as the base year, since it would produce much larger red columns of the firsts...

As requested, below is an alternate version showing how 2012 has fared. Thus far in the current year, 2012 has only had four 2nd lowest and four 3rd lowest places - all in the range 30th January until 6th of February. In each case, 2017 had a lower value.

The large swathe of lowest positions held by 2012 occurs between 25th July and 15th October (incl), so there cannot be any change in these numbers for about another 16 weeks.

The progression of the actual 2012 "lowest 3" numbers is as follows...

posn.   2012   2013   2014   2015   2016   current
lowest   131   131   131   130   83   83
second   52    49    48    43    61    57
third..    34    35    33    31    31    31
                     
total      217   215   212   204   175   171

It can therefore be easily seen that 2013, 2014 and 2015 had little impact upon the 2012 figures, but that 2016 most certainly did.


An additional diagram has also been attached. This shows how each year from 2004-2015 has changed between...
a) the end of 2015
b) the end of 2016
c) the day number shown for 2017

For 2016, it is obvious that only variants b) & c) exist. Similarly, only c) exists for 2017.

Basically, that diagram uses the status as at the end of 2015 as its starting point. It then shows the effect that 2016 had, and 2017 continues to have, upon the number of "lowest 3" positions held by previous years.
Title: Re: The 2017 melting season
Post by: Lord M Vader on April 04, 2017, 09:09:26 PM
ECMWF op 12z run is more or less a complete disaster if it comes true with a BIG 1040-1045 hpa high pressure dome over Laptev Sea. Damage: HEAVY!

The forecast might be related to that a Stratospheric Final Warming (SFW) seems to be in place right now.

GFS 12z op run agrees about the high pressure but puts it to Beaufort Sea where the "Garlic Press" might go into high gear. Damage: SEVERE!

Neither of these two solutions seems aptly for the Arctic sea ice and both of them might have a strong impact on the upcoming melting season.

To add another sober thing is that Tropical Tidbits new forecast tool for SSTA over the Pacific shows some hints of a RETROGRADE "Godzilla El Niño"... Link to the tool: http://www.tropicaltidbits.com/analysis/models/?model=cfs-mon&region=nhem&pkg=Tocean_eqx&runtime=2017040400&fh=1&xpos=0&ypos=1014.54541015625 (http://www.tropicaltidbits.com/analysis/models/?model=cfs-mon&region=nhem&pkg=Tocean_eqx&runtime=2017040400&fh=1&xpos=0&ypos=1014.54541015625)

Here is the Tropical Tidbits most recent GFS forecast for October. (http://www.tropicaltidbits.com/analysis/models/cfs-mon/2017040400/cfs-mon_01_Tocean_eqx_none_6.png)
Title: Re: The 2017 melting season
Post by: magnamentis on April 04, 2017, 11:37:54 PM
JimboOmega, this year is already objectively different from all other recent years by its winter PIOMAS results. I hope you call this a measurement even though it's mostly a model.
I expect 2017 to reach:
Record low volume with very high probability.
Record low area with high probability.
Record low JAXA extent with 50-50 probability.
Yes the weather can do all sorts of wonders, but at some point it's just average weather that brings the record.

To my mind:
2015 had a big thick chunk of ice in the Beaufort, and warm El Nino weather.

In 2016, the less thick chunk of ice had migrated to the ESS and Laptev, there was still warm El Nino weather, and a strong August storm dispersed a lot of ice to the South.

In 2017, the thick chunks of ice are gone, the El Nino weather is gone, and it seems like there's a 20% to 25% chance of a strong August storm.

I think the El Nino warmth had an effect on the Pacific side, but not much effect elsewhere.  So I'll guess that the minimum extent will probably be near the 2007, 2015, 2016 minimums, with a 20% to 25% chance of a strong August storm setting a new record.

I wonder if dispersal of ice to the South in early April would tend to cool off the southern oceans while leaving time for the CAB to rethicken?

i find it interesting to read through all the different thoughts as to what to expect and it's very legit to share thoughts like yours but to predict storminess in august or chance of such goes a bit far IMO. as far as "weather" is concerned we should just see what will be as long as we cannot even predict more than 3 days and perhaps an idea of 10 days. further the current situation cannot be compared to recent years for many reasons but one is that we are very much in uncharted waters. more open and warmer waters will favour storms like in the recent past and since i as well don't (can't) know i just say, let's concentrate on the parts that we have reliable information that allows at least for some kind of reasonable assumptions and conclusions.
Title: Re: The 2017 melting season
Post by: magnamentis on April 04, 2017, 11:41:06 PM
Pardon the pun, but watching the ease of ice transport in some of the preceding animations is truly chilling. Whilst there are still Freezing Degree Days getting clocked up in the High Arctic, it does seem a case of "too little, too late".

The fact that, purely in terms of extent, the 2017 melt season appears to have somewhat stalled at the moment, simply serves as a reminder of what transpired during 2012. If one ranks the March, April and May NSIDC monthly averages, 2012 currently occupies 14th, 20th and 13th lowest positions respectively. However, the horror show only really began in June of that year. Given that the present extent is nearly 1 million sq kms lower than that recorded for the equivalent date in 2012 should certainly give cause for apprehension.

One of the (many) ways of graphically illustrating what has been happening to Arctic sea ice is to display the number of days in each year that either has been, or indeed still is, amongst the lowest three recorded for the date.

Possibly the best example - certainly the best I can think of - is to show how 2007 has fared. According to the inhabitants of flat-land, that year was supposed to represent the nadir for Arctic sea ice. A major strand of the "logic" - and I use that word very advisedly - behind this hypothesis, was that the September minimum had increased in each of the two following years. Using NSIDC average monthly values, the September figures for Arctic sea ice extent were...

2007 = 4.32 millions sq kms
2008 = 4.73 millions sq kms
2009 = 5.39 millions sq kms

So, there is no arguing with the fact that 2009 > 2008 > 2007. The format of that inequality, allied with the fact that there had been anomalously high temperatures recorded in the Arctic during the 40's, had been used to peddle the myth that 2008 and 2009 heralded the fact that the turning point had been passed in an ~ 60 year cycle. This immediately gained uncritical acceptance in flat-land, as the average climate change sceptic wouldn't know what genuine scepticism was if it jumped up and bit them on the arse.

However, the following inequalities between NSIDC average September extents somehow seemed to have been overlooked...

1983 > 1982 > 1981
1992 > 1991 > 1990
2001 > 2000 > 1999

(Incidentally, the increase between 1990 and 1992 was quarter of a million sq kms greater than the much-vaunted 2007 - 2009 "recovery".)

{Of course, things have moved on since them, and their current meme is that the Arctic was effectively ice free nearly 100 years ago. There were so many obvious flaws in the original 60-year cycle meme, that even committee members in the House and the Senate would have had trouble keeping a straight face.}

Anyway, getting back to 2007, according to the JAXA/IJIS/ADS database, by the 31st December that year, it had registered the following daily figures...

153 days were lowest for that date
104 days were second lowest, and
105 days were third lowest. (That adds up to 362, and the other 3 days were 4th lowest.)

However, as at today, the equivalent numbers for 2007 read as follows...

Lowest: 4 days
2nd lowest: 70 days
3rd lowest: 46 days

The demise of 2007 from its position of preeminence can be seen in the attached chart. The first column shows how 2007 stood at year-end, and the subsequent columns show the decline at the end of each of the following years. The final column tracks in near-real-time as 2017 data arrives. So far this year, there have only been 8 "lowest 3" instances remaining from 2007. Each of them has been surpassed in 2017, with 2 dropping to 3rd lowest, and a further 6 dropping to 4th. As the 2017 melt season gets into gear, it will be "interesting" to see how much further 2007 will sink.


As we frequently say in Glasgow...

sic transit gloria mundi

you hit the nail on the head, 1+, seconding every letter, nice read indeed, thanks
Title: Re: The 2017 melting season
Post by: Tigertown on April 04, 2017, 11:59:07 PM
Baffin is really moving some ice lately.
(http://)
Title: Re: The 2017 melting season
Post by: Adam Ash on April 05, 2017, 03:25:54 AM
Baffin is really moving some ice lately.
(http://)

Indeed.  Davis Straight is about 330 km wide at the narrowest there (on the Arctic Circle, thereabouts).  Measuring a big floe 17th to 23rd March which moved 100 km over those five days and assuming an average ice thickness of 1 metre gives an export of 6.6 cubic kilometres of ice per day.  That is darn a big ice-block to freeze, and quite a loss to the basin.  I've no data to tell whether this is in any way an unusual loss rate and how it compares, say, with Fram et al.  But it sure is an impressive number.
Title: Re: The 2017 melting season
Post by: jdallen on April 05, 2017, 05:04:25 AM
Baffin is really moving some ice lately.
(http://)

Indeed.  Davis Straight is about 330 km wide at the narrowest there (on the Arctic Circle, thereabouts).  Measuring a big floe 17th to 23rd March which moved 100 km over those five days and assuming an average ice thickness of 1 metre gives an export of 6.6 cubic kilometres of ice per day.  That is darn a big ice-block to freeze, and quite a loss to the basin.  I've no data to tell whether this is in any way an unusual loss rate and how it compares, say, with Fram et al.  But it sure is an impressive number.
That movement is un-blocking ice coming out of Hudson's bay and opening the NW Passage up to pressure from tidal movement.

Looking at all of the exits - Bering, Barents, Fram, Baffin - it seems like a general "Un-corking" is taking place.
Title: Re: The 2017 melting season
Post by: Paladiea on April 05, 2017, 07:22:56 AM
It seems to me that this year is looking more and more like a tipping point. Considering the thermodynamics of the situation, it only makes sense that there would be so much heat available for melt/dispersion this early in the year considering all the methane hanging around. We know that methane is 80-100 times as potent as carbon dioxide in terms of scattering radiation at the wavelengths that Earth emits, and we've had a couple of years of that elevated methane to do its work.

I'm throwing my chips in for a complete rout of the Arctic sea ice this year. I may be wrong, but if it's not going to be 2017, it will definitely be before 2020.
Title: Re: The 2017 melting season
Post by: Aikimox on April 05, 2017, 08:46:43 AM
It seems to me that this year is looking more and more like a tipping point. Considering the thermodynamics of the situation, it only makes sense that there would be so much heat available for melt/dispersion this early in the year considering all the methane hanging around. We know that methane is 80-100 times as potent as carbon dioxide in terms of scattering radiation at the wavelengths that Earth emits, and we've had a couple of years of that elevated methane to do its work.

I'm throwing my chips in for a complete rout of the Arctic sea ice this year. I may be wrong, but if it's not going to be 2017, it will definitely be before 2020.

Unless some other processes come into play. https://watchers.news/2017/03/16/active-volcanoes-in-the-world-march-8-14-2017/
March has seen a number of potent eruptions. I wouldn't be surprised to see a cooling effect reflected in global average temperatures March-April.
Title: Re: The 2017 melting season
Post by: etienne on April 05, 2017, 09:19:55 AM
Unless some other processes come into play. [url]https://watchers.news/2017/03/16/active-volcanoes-in-the-world-march-8-14-2017/[/url] ([url]https://watchers.news/2017/03/16/active-volcanoes-in-the-world-march-8-14-2017/[/url])
March has seen a number of potent eruptions. I wouldn't be surprised to see a cooling effect reflected in global average temperatures March-April.


Hello,

I made a fast check of main volcanic activity, google gives mainly 1980 Mount St Helen and 1991 Pinatobo, but on the north side of the world, there was also the Eyjafjöll in 2010 that stopped air trafic in Europe.

I don't see any impact on the Piomas trend line.

(http://psc.apl.uw.edu/wordpress/wp-content/uploads/schweiger/ice_volume/BPIOMASIceVolumeAnomalyCurrentV2.1.png)

I don't know. Maybe volcanic activity has positive and negative feed backs.

Etienne
Title: Re: The 2017 melting season
Post by: Cid_Yama on April 05, 2017, 09:21:29 AM
It seems to me that this year is looking more and more like a tipping point. Considering the thermodynamics of the situation, it only makes sense that there would be so much heat available for melt/dispersion this early in the year considering all the methane hanging around. We know that methane is 80-100 times as potent as carbon dioxide in terms of scattering radiation at the wavelengths that Earth emits, and we've had a couple of years of that elevated methane to do its work.

I'm throwing my chips in for a complete rout of the Arctic sea ice this year. I may be wrong, but if it's not going to be 2017, it will definitely be before 2020.

Agreed.  I had a heart attack on New Years Day and my only thought was, "Not now, this is the year, I don't want to miss it." (Don't tell my wife)  ;)
Title: Re: The 2017 melting season
Post by: romett1 on April 05, 2017, 09:34:12 AM
Latest GFS anomalies until next Wednesday and 5-day outlook (Climate Reanalyzer). Seems like next week anomalies north of °65 are lowest seen for quite a long time as long-term mean temperatures now start to rise.
Title: Re: The 2017 melting season
Post by: Cid_Yama on April 05, 2017, 09:37:02 AM
Looks like it's setting up for a Siberian high. 
Title: Re: The 2017 melting season
Post by: seaicesailor on April 05, 2017, 09:40:02 AM
Latest GFS anomalies until next Wednesday and 5-day outlook (Climate Reanalyzer). Seems like next week anomalies north of °65 are lowest seen for quite a long time as long-term mean temperatures now start to rise.
Thanks Romett for putting together this info every day, really nice to see it
Title: Re: The 2017 melting season
Post by: Paladiea on April 05, 2017, 09:57:36 AM
Unless some other processes come into play. https://watchers.news/2017/03/16/active-volcanoes-in-the-world-march-8-14-2017/
March has seen a number of potent eruptions. I wouldn't be surprised to see a cooling effect reflected in global average temperatures March-April.

The only things that volcanic activity can do to alter the planetary heat balance (and thus affect the Arctic and the ice) is to emit carbon dioxide (which can warm the planet if sustained and large enough) or emit ash (which reflects incoming solar radiation back into space, causing a cooling effect). I don't know about you, but the atmosphere doesn't look especially hazy at the moment.

Anyhow back to the ice. I mentioned last year that even though insolation was the most efficient way for heat to enter the Arctic, many other inefficient mechanisms could add up to the equivalent transfer, or greater.
Title: Re: The 2017 melting season
Post by: John on April 05, 2017, 10:06:51 AM
It seems to me that this year is looking more and more like a tipping point. Considering the thermodynamics of the situation, it only makes sense that there would be so much heat available for melt/dispersion this early in the year considering all the methane hanging around. We know that methane is 80-100 times as potent as carbon dioxide in terms of scattering radiation at the wavelengths that Earth emits, and we've had a couple of years of that elevated methane to do its work.

I'm throwing my chips in for a complete rout of the Arctic sea ice this year. I may be wrong, but if it's not going to be 2017, it will definitely be before 2020.


Agreed.  I had a heart attack on New Years Day and my only thought was, "Not now, this is the year, I don't want to miss it." (Don't tell my wife)  ;)

I do want to miss it on the other hand, although not because of a heart attack. I have a two year old kid. I want everything to be normal while we solve world hunger. No drought, no melting ice, no global warming, no wars, just boring growing up with skinned knees and occasional tummy aches from too many apples.
Title: Re: The 2017 melting season
Post by: slow wing on April 05, 2017, 10:21:52 AM
Looks like it's setting up for a Siberian high.
Yes, I'm thinking that should offer some temporary respite for the ice, following all the strong low pressure systems of past weeks.

  The forecast winds around the Arctic basin over the next several days are relatively weak and, with the sun still low on the horizon, clear skies from the high should allow long wave thermal radiation to escape to space without the ice being exposed to too much down going short wave radiation.
Title: Re: The 2017 melting season
Post by: Cid_Yama on April 05, 2017, 10:31:05 AM
John, if I had the power I would give that to you, and all the other parents out there.  That is what makes this so tragic.  Think quality not quantity.  One can live a full life without it being a long one.  Live for today.
Title: Re: The 2017 melting season
Post by: subgeometer on April 05, 2017, 11:50:57 AM
High pressure has come too late to thicken iced and if it persists into May and June that won't be good, though it's getting harder to imagine weather that will be good for the ice given the heat in the system.  A cold cloudy still summer maybe. The band 31 images JD posted a few days showing much greater warmth on the Russian side are alarming, is it just due to the very thin ice there or is the current from the Atlantic also being mixed more with the surface

Ice is an Esky on a hot Australian Christmas will seem hardly to melt for ages then be gone in minutes, I fear we might see enormous extent drops later in the season given all this dispersion and 1m ice in Beaufort, wafer thin in ESS etc. We've only just passed the 1.5m mark in new ice growth above 80N according to Lebedev
Title: Re: The 2017 melting season
Post by: crandles on April 05, 2017, 01:39:06 PM


I made a fast check of main volcanic activity, google gives mainly 1980 Mount St Helen and 1991 Pinatobo, but on the north side of the world, there was also the Eyjafjöll in 2010 that stopped air trafic in Europe.



Mount St Helens was mainly sideways, and Eyjafjöll wasn't big enough so neither caused much to get up into stratosphere. If only tropospheric then it quickly rains out.

Pinatubo and El Chichon are the largest most recent two sufficient to cause global temperature effect.

http://rmrco.com/cruise/ata/reports/100422_Aerosols_Volcanos/index.html (http://rmrco.com/cruise/ata/reports/100422_Aerosols_Volcanos/index.html)
Title: Re: The 2017 melting season
Post by: Neven on April 05, 2017, 02:11:59 PM
Kara Sea southwest of Novaya Zemlya definitely icing over now. And so we wait for the winds to turn...
Title: Re: The 2017 melting season
Post by: romett1 on April 05, 2017, 02:35:05 PM
Let's also not forget fresh FDD anomaly chart north of 80°. April has started pretty badly, as temperatures are currently highest since February spike there. And next 5 days are still warmer than usual north of 80°, except area from Svalbard to North Pole. Also not trying to compare this season vs 2012/2013. Source: http://ocean.dmi.dk/arctic/meant80n.uk.php (http://ocean.dmi.dk/arctic/meant80n.uk.php) and https://sites.google.com/site/arcticseaicegraphs/ (https://sites.google.com/site/arcticseaicegraphs/)
Title: Re: The 2017 melting season
Post by: Shared Humanity on April 05, 2017, 02:39:54 PM
Kara Sea southwest of Novaya Zemlya definitely icing over now. And so we wait for the winds to turn...

Looks like some noticeable melt of the ice pushing into the Barents though.
Title: Re: The 2017 melting season
Post by: Andreas T on April 05, 2017, 03:02:51 PM
There is melting along the southern edge of the ice southeast of Svalbard but also some compaction in a northwesterly direction which combines to show a receding ice edge there.
see https://go.nasa.gov/2oHYl3x (https://go.nasa.gov/2oHYl3x)
 New ice has been formed on the western coast of Novaya Zemlya. This won't last long when the wind turns, water temperatures are too high I think.
Title: Re: The 2017 melting season
Post by: dnem on April 05, 2017, 03:40:19 PM
There has been some speculation here about whether the forecast temperature anomalies helpfully posted by romett1 have a cold bias in the later days as the model (GFS) defers more to (colder) climatology compared to current weather.  I subtracted the forecast anomaly from the current day's anomaly reported in romett1's posts for the past couple of weeks, for lags of 5, 6 and 7 days.  There is a pervasive cold bias in the forecasts.  Almost every anomaly reported for a given day is higher than what it was forecast to be 5-7 days earlier.
Title: Re: The 2017 melting season
Post by: Aikimox on April 05, 2017, 04:08:43 PM


I made a fast check of main volcanic activity, google gives mainly 1980 Mount St Helen and 1991 Pinatobo, but on the north side of the world, there was also the Eyjafjöll in 2010 that stopped air trafic in Europe.



Mount St Helens was mainly sideways, and Eyjafjöll wasn't big enough so neither caused much to get up into stratosphere. If only tropospheric then it quickly rains out.

Pinatubo and El Chichon are the largest most recent two sufficient to cause global temperature effect.

[url]http://rmrco.com/cruise/ata/reports/100422_Aerosols_Volcanos/index.html[/url] ([url]http://rmrco.com/cruise/ata/reports/100422_Aerosols_Volcanos/index.html[/url])


Thank you for the clarification and link, good read.
Title: Re: The 2017 melting season
Post by: oren on April 05, 2017, 05:10:55 PM
There has been some speculation here about whether the forecast temperature anomalies helpfully posted by romett1 have a cold bias in the later days as the model (GFS) defers more to (colder) climatology compared to current weather.  I subtracted the forecast anomaly from the current day's anomaly reported in romett1's posts for the past couple of weeks, for lags of 5, 6 and 7 days.  There is a pervasive cold bias in the forecasts.  Almost every anomaly reported for a given day is higher than what it was forecast to be 5-7 days earlier.
Thank you dnem. I knew it!
Title: Re: The 2017 melting season
Post by: Jim Williams on April 05, 2017, 08:50:08 PM
I suppose I ought to figure out how to show a pretty picture of this, but at this time last year the DMI 80N was beginning to hug the climatology and we were all remarking upon how consistently warm it had been.  This year, as of today the current temps are well away from hugging climatology.
Title: Re: The 2017 melting season
Post by: DrTskoul on April 05, 2017, 09:29:54 PM
2011 had similarly high march/ early April temperatures...
Title: Re: The 2017 melting season
Post by: Jim Williams on April 05, 2017, 10:22:30 PM
2011 had similarly high march/ early April temperatures...
Correct, however they fell to climatology just about NOW after a bulge, where this year there has been a single drop to slightly above climatology.  Given the corresponding histories, do you want to place bets?

Title: Re: The 2017 melting season
Post by: magnamentis on April 05, 2017, 10:31:30 PM
2011 had similarly high march/ early April temperatures...

there is for every event a point in time that was similar, the point is that we are consistently warmer and if we have a spike it's upward and except one single time not downward temp-wise and the only down spikes never reached the average line. IMO it' makes little sense to sooth the situation by pointing out when in the past it was similarly warm because that year in the past mostly if not always was cold or very cold before and after that event while the last few were not, 2016/17 especially.
Title: Re: The 2017 melting season
Post by: JayW on April 05, 2017, 10:50:41 PM
April 1-5

Alaska in bottom center

http://feeder.gina.alaska.edu/npp-gina-alaska-truecolor-images?search%5Bfeeds%5D%5B5%5D=1&search%5Bsensors%5D%5B3%5D=1 (http://feeder.gina.alaska.edu/npp-gina-alaska-truecolor-images?search%5Bfeeds%5D%5B5%5D=1&search%5Bsensors%5D%5B3%5D=1)
Title: Re: The 2017 melting season
Post by: Downpuppy on April 05, 2017, 11:09:43 PM
Not sure where this fits, but 450 icebergs suddenly appearing around the Grand Banks makes melting season real.

https://www.boston.com/news/national-news/2017/04/05/unusually-large-swarm-of-icebergs-drifts-into-shipping-lanes (https://www.boston.com/news/national-news/2017/04/05/unusually-large-swarm-of-icebergs-drifts-into-shipping-lanes)
Title: Re: The 2017 melting season
Post by: oren on April 05, 2017, 11:13:51 PM
Regarding DMI's 80N temps, the forecast as posted by romett seems to imply that temps are generally expected to drop in the next few days. Who knows, we might get that climatology hug after all. Although even if we do, the FDD damage has already been done, as can also be seen in the latest PIOMAS numbers.
Title: Re: The 2017 melting season
Post by: Jim Williams on April 05, 2017, 11:21:10 PM
Regarding DMI's 80N temps, the forecast as posted by romett seems to imply that temps are generally expected to drop in the next few days. Who knows, we might get that climatology hug after all. Although even if we do, the FDD damage has already been done, as can also be seen in the latest PIOMAS numbers.
I assume it's got to happen eventually.  We are not out of ice up there yet.  But the gap between where we are and where we used to be at this time of year is really obvious.  We are still seeing the switch at the end of 2015, and no backsliding.

I might change my mind and expect summertime temps to jump above the climatology sometime late this summer.
Title: Re: The 2017 melting season
Post by: seaicesailor on April 06, 2017, 12:02:50 AM
April 1-5

Alaska in bottom center

[url]http://feeder.gina.alaska.edu/npp-gina-alaska-truecolor-images?search%5Bfeeds%5D%5B5%5D=1&search%5Bsensors%5D%5B3%5D=1[/url] ([url]http://feeder.gina.alaska.edu/npp-gina-alaska-truecolor-images?search%5Bfeeds%5D%5B5%5D=1&search%5Bsensors%5D%5B3%5D=1[/url])

So the chances of Beaufort sea ice to survive rapidly diminish, as early as April, I believe these cracks will seed the albedo feedback come May just as past two seasons. The drift is going to continue for at least one week.
Not good. Thinnest ice overall ever (recorded), but the details are not better, eurasian side looks already like crap from Kara sea to ESS, and the MYI cannot be more compromised toward the Atlantic.
Title: Re: The 2017 melting season
Post by: ipexnet on April 06, 2017, 06:28:06 AM
I think the below is a bit deceptive, as last year I think we saw much more of this north of alaska. But doesn't diminish the general concept that everyone has been noting - the ice pack appears much more susceptible to winds and transport.

April 1-5

Alaska in bottom center

[url]http://feeder.gina.alaska.edu/npp-gina-alaska-truecolor-images?search%5Bfeeds%5D%5B5%5D=1&search%5Bsensors%5D%5B3%5D=1[/url] ([url]http://feeder.gina.alaska.edu/npp-gina-alaska-truecolor-images?search%5Bfeeds%5D%5B5%5D=1&search%5Bsensors%5D%5B3%5D=1[/url])
Title: Re: The 2017 melting season
Post by: John on April 06, 2017, 08:40:10 AM
John, if I had the power I would give that to you, and all the other parents out there.  That is what makes this so tragic.  Think quality not quantity.  One can live a full life without it being a long one.  Live for today.

I think that was the most depressing comment on the boards ever. I realize the intentions were good.

I also fear this season; we have watched global warming gradually, now it is here and occurs suddenly.
Title: Re: The 2017 melting season
Post by: romett1 on April 06, 2017, 09:52:12 AM
There has been some speculation here about whether the forecast temperature anomalies helpfully posted by romett1 have a cold bias in the later days as the model (GFS) defers more to (colder) climatology compared to current weather.  I subtracted the forecast anomaly from the current day's anomaly reported in romett1's posts for the past couple of weeks, for lags of 5, 6 and 7 days.  There is a pervasive cold bias in the forecasts.  Almost every anomaly reported for a given day is higher than what it was forecast to be 5-7 days earlier.
Thank you dnem. I knew it!

Thank you dnem for calculations. I was wondering as well, almost each day I had to upgrade anomalies higher. So I marked days 5 - 7 grey, as they are not too reliable.
Latest GFS anomalies and 5-day forecast (Climate Reanalyzer). Seems like all anomalies are now higher. Currently showing cyclone entering the Arctic through Bering Strait Apr 12 bringing strong winds over Bering Sea, Bering Strait and Chukchi Sea and of course higher temperatures. This is next Wednesday, have to wait and see. We know ice is not too strong there.
Title: Re: The 2017 melting season
Post by: JayW on April 06, 2017, 10:00:15 AM
I think the below is a bit deceptive, as last year I think we saw much more of this north of alaska. But doesn't diminish the general concept that everyone has been noting - the ice pack appears much more susceptible to winds and transport.

April 1-5

Alaska in bottom center

[url]http://feeder.gina.alaska.edu/npp-gina-alaska-truecolor-images?search%5Bfeeds%5D%5B5%5D=1&search%5Bsensors%5D%5B3%5D=1[/url] ([url]http://feeder.gina.alaska.edu/npp-gina-alaska-truecolor-images?search%5Bfeeds%5D%5B5%5D=1&search%5Bsensors%5D%5B3%5D=1[/url])



We can split hairs if you like.

Last year had much more multi year ice, I doubt we see anything analogous to the "big block" as the ice appears to be breaking into smaller pieces.  My humble opinion.

First attachment is from April 5, 2017
Second attachment is April 5, 2016

http://feeder.gina.alaska.edu (http://feeder.gina.alaska.edu)
Title: Re: The 2017 melting season
Post by: Cate on April 06, 2017, 11:52:49 AM
Not sure where this fits, but 450 icebergs suddenly appearing around the Grand Banks makes melting season real.

https://www.boston.com/news/national-news/2017/04/05/unusually-large-swarm-of-icebergs-drifts-into-shipping-lanes (https://www.boston.com/news/national-news/2017/04/05/unusually-large-swarm-of-icebergs-drifts-into-shipping-lanes)

Yes, there was a huge icefield NE and E of Newfoundland, extending out from the coast many hundreds of km, until about last Thursday (Mar 30). That's when the first of two massive back-to-back nor-easters tore into the pack with its accompanying bergs and scattered it far and wide across NW Atlantic shipping lanes.

Check out the Canadian Ice Service charts for recent analysis of NE Atlantic coastal/eastern Canadian Arctic ice.

https://www.theguardian.com/environment/2017/apr/06/huge-fleet-icebergs-north-atlantic-shipping-lanes (https://www.theguardian.com/environment/2017/apr/06/huge-fleet-icebergs-north-atlantic-shipping-lanes)
Title: Re: The 2017 melting season
Post by: seaicesailor on April 06, 2017, 12:55:37 PM
I think the below is a bit deceptive, as last year I think we saw much more of this north of alaska. But doesn't diminish the general concept that everyone has been noting - the ice pack appears much more susceptible to winds and transport.

April 1-5

Alaska in bottom center

[url]http://feeder.gina.alaska.edu/npp-gina-alaska-truecolor-images?search%5Bfeeds%5D%5B5%5D=1&search%5Bsensors%5D%5B3%5D=1[/url] ([url]http://feeder.gina.alaska.edu/npp-gina-alaska-truecolor-images?search%5Bfeeds%5D%5B5%5D=1&search%5Bsensors%5D%5B3%5D=1[/url])



I think it is really bad, my honest opinion. The second comparison above by Jay shows that we can end up with a pretty extensive web of cracks and (worse) coastal openings, and while this does not have the size of 2016 event at all, it already establishes sinks of solar radiation heat from May on. It seemed this year Beaufort sea might have spared this (or delayed it enough) but no. And let us remember, no MYI here whatsoever.
Title: Re: The 2017 melting season
Post by: Lord M Vader on April 06, 2017, 04:19:26 PM
Interesting article from Guardian wrt the high number of icebergs in the North Atlantic due to "uncommonly strog counter-clockwise winds".

https://www.theguardian.com/environment/2017/apr/06/huge-fleet-icebergs-north-atlantic-shipping-lanes (https://www.theguardian.com/environment/2017/apr/06/huge-fleet-icebergs-north-atlantic-shipping-lanes)
Title: Re: The 2017 melting season
Post by: Thomas Barlow on April 06, 2017, 04:35:50 PM
Tried to post this to Neven's blog (didn't work). Any comments? :

What's really worrying is that they include recent years (mostly low volume years) in their 'mean volume 1979-2016'.
That means the black line will be getting lower each year, as recent years are added to the mean.
If they just used 1979-2000 (as Climate-Reanalyser does for temperatures), then the black line would be much higher up the chart (not that that period alone would be enough to show average though). What do the ice cores, taken from at least the 1970s, show, about the longer-term past of the Arctic?

http://neven1.typepad.com/blog/2017/04/piomas-april-2017.html (http://neven1.typepad.com/blog/2017/04/piomas-april-2017.html)
.

<Take it to the PIOMAS thread, Thomas,s'il vous plaît; N.>
Title: Re: The 2017 melting season
Post by: Tigertown on April 06, 2017, 09:40:30 PM
Uhh-ohh! Looks like this is about to really open up now.
Svalbard on the right.
1st vs 6th
CLICK IMAGE TO ACTIVATE
(http://)
Title: Re: The 2017 melting season
Post by: Bill Fothergill on April 06, 2017, 09:50:28 PM
...
What's really worrying is that they include recent years (mostly low volume years) in their 'mean volume 1979-2016'. That means the black line will be getting lower each year, as recent years are added to the mean...

...What do the ice cores, taken from at least the 1970s, show, about the longer-term past of the Arctic?
[url]http://neven1.typepad.com/blog/2017/04/piomas-april-2017.html[/url] ([url]http://neven1.typepad.com/blog/2017/04/piomas-april-2017.html[/url])


I confess I had not noticed that the Mean Volume on PIOMAS was a movable feast until you pointed it out. Perhaps Jim Pettit, or somebody like that, might be able to shed some light on why it has been done that way. You are certainly correct in saying that the repeated inclusion of the more recent results is going to pull the Mean downwards.

Regarding Greenland drilling, you might want to do a Google on Greenland Ice Sheet Project (GISP) or Greenland Ice Core Project (GRIP), or, for starters, try...
http://www.iceandclimate.nbi.ku.dk/research/past_atmos/ (http://www.iceandclimate.nbi.ku.dk/research/past_atmos/)

http://www.nbi.ku.dk/english/news/news13/greenland-ice-cores-reveal-warm-climate-of-the-past/ (http://www.nbi.ku.dk/english/news/news13/greenland-ice-cores-reveal-warm-climate-of-the-past/)

More recently, there was the North Greenland Eemian Ice Drilling Project (NEEM).
http://neem.dk/ (http://neem.dk/)
Title: Re: The 2017 melting season
Post by: jai mitchell on April 06, 2017, 10:03:32 PM
4 day forecast on nullschool shows a self-generated low in the Barents.  This looks favorable for ice export and compaction north of Svalbard for at least the next week.

https://earth.nullschool.net/#2017/04/10/1200Z/wind/surface/level/orthographic=42.55,72.85,816
Title: Re: The 2017 melting season
Post by: Bill Fothergill on April 06, 2017, 10:06:11 PM
...  nice read indeed ...

Thank you for the kind words!  ;)

If you enjoyed that, you might also like...

http://neven1.typepad.com/blog/2013/05/party-like-its-1989.html#more (http://neven1.typepad.com/blog/2013/05/party-like-its-1989.html#more)

http://greatwhitecon.info/2017/02/shock-news-19-years-without-warming/ (http://greatwhitecon.info/2017/02/shock-news-19-years-without-warming/)

http://greatwhitecon.info/2016/03/how-to-make-a-complete-rss-of-yourself/ (http://greatwhitecon.info/2016/03/how-to-make-a-complete-rss-of-yourself/)
Title: Re: The 2017 melting season
Post by: magnamentis on April 06, 2017, 10:28:12 PM
Uhh-ohh! Looks like this is about to really open up now.
Svalbard on the right.
1st vs 6th
CLICK IMAGE TO ACTIVATE
(http://)

looks like a massive bridge-head directly pointing to the pole, considering recent mobility of the core ice that's boding not well indeed. thanks for the repeating great images, very useful stuff.

@Bill Fothergill
you're welcome, thx for the links, those should be prominently place somewhere on the ASIG page IMO, i wish my english would allow for such great articles. kudos, very exiting content.

EDIT: i assume you allow that i posted those on my facebook profile, else let me know
Title: Re: The 2017 melting season
Post by: Greenbelt on April 06, 2017, 11:37:33 PM
Both GFS and ECMWF deterministic runs indicating lots of high pressure. Here are 120 and 240 hours from each. Too early for the sun to do much preconditioning?

(http://www.tropicaltidbits.com/analysis/models/ecmwf/2017040612/ecmwf_z500_mslp_nhem_6.png)
(http://www.tropicaltidbits.com/analysis/models/ecmwf/2017040612/ecmwf_z500_mslp_nhem_11.png)

(http://www.tropicaltidbits.com/analysis/models/gfs/2017040612/gfs_z500_mslp_nhem_21.png)
(http://www.tropicaltidbits.com/analysis/models/gfs/2017040612/gfs_z500_mslp_nhem_41.png)
Title: Re: The 2017 melting season
Post by: Bill Fothergill on April 07, 2017, 12:40:42 AM
Almost by definition, anyone looking at this particular thread will be very interested in just how the 2017 melt season is going to eventually pan out. One of the key factors is undoubtedly going to be the volume of sea ice that is currently still in existence up in the Arctic. Anyone not yet familiar with the excellent graphics provided by (amongst others) Wipneus and Jim Pettit should have a look at the material available on their websites.

The Arctic Sea Ice Graphs page contains the relevant links...
https://sites.google.com/site/arcticseaicegraphs/

I wondered how helpful the NSIDC monthly values (for both extent and area) could be, in terms of helping people to come up with early ballpark figures for where they think that 2017 might end up. In order to present the data in what is hopefully an understandable fashion, I have shamelessly plagiarised one of Jim's graphs.

There are two attached charts; the first looks at extent and the second at area. However, the layouts are identical in each case.

The top of the blue bars indicates the monthly average at the March maximum for each year, and the actual value is given as a data label above the bar.

The red bars represent the difference between the March average (i.e. the maximum) and the September average (i.e. the minimum). This obviously equates to the amount of ice that melted (or was exported, or disappeared by any other mechanism) during the melt season. (Each actual value is shown within the relevant red bar.)

The length of each blue bar corresponds to the monthly average at the relevant September minimum, i.e. the ice remaining at the end of each melt season. (Again, the actual values are given within each of the blue bars.)

What should be painfully clear is that there is a double whammy going on. Not only is the average maximum value decreasing, but the average loss leading up to the minimum is increasing. As a consequence, the ice remaining at the September minimum is feeling the pinch - from both sides.

A simple 2nd-order polynomial trend has been applied at the top and bottom of each chart (extent and area) and their convergence is merely a matter of "when", not "if". (N.B. The trend lines have been extended only as far as 2020, as different choices of trend-type rapidly diverge.)

Given the dearth of multi-year ice, and the extensive export/transport which already seems to be well under way, one wonders if those trend lines are horribly understating the reality.


Once again, the idea for this type of chart came from Jim Pettit's site.
Title: Re: The 2017 melting season
Post by: dnem on April 07, 2017, 12:51:26 AM
What should be painfully clear is that there is a double whammy going on. Not only is the average maximum value decreasing, but the average loss leading up to the minimum is increasing. As a consequence, the ice remaining at the September minimum is feeling the pinch - from both sides.

Bill - Today I sent a link to Jim's PIOMAS chart that you "plagiarized" to a concerned but non-ice-obsessed neighbor, as I thought it was an excellent graphic.  I titled the email "A classic pincer move," a term from military strategy where you attack an enemy from two flanks simultaneously.
Title: Re: The 2017 melting season
Post by: Feeltheburn on April 07, 2017, 03:29:15 AM
Is someone going to post a poll regarding predictions for this year's summer low?
Title: Re: The 2017 melting season
Post by: Tigertown on April 07, 2017, 04:17:23 AM
The Beaufort. April 3rd-6th
(http://)
Title: Re: The 2017 melting season
Post by: bbr2314 on April 07, 2017, 04:20:44 AM
The Beaufort. April 3rd-6th

(https://media.giphy.com/media/aEP74JYRkSTzW/giphy.gif)
Title: Re: The 2017 melting season
Post by: jgnfld on April 07, 2017, 07:53:35 AM
Re. Newfoundland...

There have been 2 strong nor'easters here which have blown the pack which normally resides to the NE of the Avalon at this time of the year into shore. Conception Bay, Bonavista Bay, and Trinity Bay are quite covered. There are a few small bergs mixed in with the pack in Conception Bay, at least, which can be seen from shore. At least one polar bear has come ashore at Bonavista. One of the container ships which supplies the island took a hit apparently from a growler or bergy bit mangling its bulbous underwater bow in the process.

The shore on the seaward side of the Avalon Peninsula was covered but with the winds changing back to southerly much of the pack there is back out to sea. The bays will be a different matter, and much slower to clear, likely.
Title: Re: The 2017 melting season
Post by: Neven on April 07, 2017, 08:34:32 AM
Is someone going to post a poll regarding predictions for this year's summer low?

Way too early. I'll be posting the first poll in June, and I would kindly ask others not to open polls before that.

It's a crap shoot either way, but projections are more solid after the first phase of the melting season has passed (April-May-first week of June).
Title: Re: The 2017 melting season
Post by: romett1 on April 07, 2017, 09:40:11 AM
Latest GFS anomalies and 5-day outlook (Climate Reanalyzer). Current forecast still shows cyclone over Bering Strait approaching Tue evening, therefore higher anomalies over Bering Sea, Chukchi Sea and Beaufort Tue - Fri next week.
Title: Re: The 2017 melting season
Post by: seaicesailor on April 07, 2017, 11:46:40 AM
Both GFS and ECMWF deterministic runs indicating lots of high pressure. Here are 120 and 240 hours from each. Too early for the sun to do much preconditioning?


Not yet I believe (see ongoing stupid questions discussions), but the last ecmwf run sees the current Beaufort high become strong and persistent. Overall Beaufort sea albedo to continue downwards (because of cracks and openings)

Second half of the animation not to be taken really seriously (that warm wave with 1050 hPa???).
Title: Re: The 2017 melting season
Post by: meddoc on April 07, 2017, 11:52:08 AM
Don' worry- Nuclear Winter is in the works.
Title: Re: The 2017 melting season
Post by: Csnavywx on April 07, 2017, 01:08:21 PM
Both GFS and ECMWF deterministic runs indicating lots of high pressure. Here are 120 and 240 hours from each. Too early for the sun to do much preconditioning?

([url]http://www.tropicaltidbits.com/analysis/models/ecmwf/2017040612/ecmwf_z500_mslp_nhem_6.png[/url])
([url]http://www.tropicaltidbits.com/analysis/models/ecmwf/2017040612/ecmwf_z500_mslp_nhem_11.png[/url])

([url]http://www.tropicaltidbits.com/analysis/models/gfs/2017040612/gfs_z500_mslp_nhem_21.png[/url])
([url]http://www.tropicaltidbits.com/analysis/models/gfs/2017040612/gfs_z500_mslp_nhem_41.png[/url])


Depends. Right now it isn't doing as much damage as it could be say -- a month from now. As it sits, that high will likely begin to pull ice away from the coasts and allow an ice front to establish. Any open water will definitely soak up the insolation. Sunlight at 70N is plenty bright enough to cause issues already.
Title: Re: The 2017 melting season
Post by: Shared Humanity on April 07, 2017, 02:28:07 PM
The Beaufort. April 3rd-6th
(http://)

That high pressure is getting things moving.
Title: Re: The 2017 melting season
Post by: Andreas T on April 07, 2017, 02:41:59 PM
It is counterintuitive to us living in lower latitudes but looking at measurements in the arctic it is striking how sunshine correlates with low temperatures, especially this early in the season. The attached temperature and pressure graph from Obuoy14 is just one further example of warmer (-10C) temperatures during lows. http://obuoy.datatransport.org/monitor#buoy14/weather (http://obuoy.datatransport.org/monitor#buoy14/weather)
look at the battery data to get an indication of sunshine (charging batteries) and cloudy weather (lower daytime voltages)
sunshine comes with clear skies which also allows increased cooling by lack of long wave radiation from clouds
Title: Re: The 2017 melting season
Post by: Sterks on April 07, 2017, 02:46:34 PM
Somebody mentioned here that March 2017 month had been the warmest on record for the Arctic, but I can't find the reference.
Nonetheless, below a quote from the global temperatures thread with a map that illustrates that fact, and the NOAA forecast for April 2017.

Guys, Copernicus just arrived with their analysis for March. No surprise here, March was the  second warmest on record and 0,10oC cooler compared to March 2016. This number make me believe that a NASA GISS anomaly around 1,07-1,15oC above the average seemsquite reasonable.

(https://climate.copernicus.eu/sites/default/files/repository/Temp_maps/Month_3_2017_plot_1_branded.jpg)

Title: Re: The 2017 melting season
Post by: Cate on April 07, 2017, 02:59:43 PM
Re. Newfoundland...

....The bays will be a different matter, and much slower to clear, likely.

All we need are a few days of sustained SW winds, and the northern bays will clear out pretty nicely. But the extent of the pack in general has taken a beating from the two recent storms, compared to say, extent in the last week of March. The Canadian Ice Service today is showing much less pack to the east, but bergy water right around to the Burin Peninsula and well down through the Strait of Belle Isle.
Title: Re: The 2017 melting season
Post by: FishOutofWater on April 07, 2017, 05:09:45 PM
It was the warmest cold season from 80N to the pole and the second warmest from the Arctic circle to the pole, if I remember the details right.

Note that the CFSv2 pattern for April is a strong wave 1 pattern with ridging over Eurasia and troughing over Canada. It's consistent with the positive PDO, developing El Niño and reactivated overturning in the Labrador and Greenland seas. It's a pattern that will lead to early ice melt in the Siberian seas.
Title: Re: The 2017 melting season
Post by: Tor Bejnar on April 07, 2017, 05:52:14 PM
I'm curious about the effect Nares Strait is having on Baffin Bay.  Specifically, Kane Basin (and the entire Strait) has not had an effective ice arch all winter, so Nares it has exported a lot of up-to-about-one-meter-thick (grown in Nares Strait) ice.  The volume (not thickness) of ice created in Nares Strait will be much greater than usual, as new ice with no snow cover is (virtually) continually being created in the northern parts of the Strait, and the first 10 or 50 cm grows much faster (in a given temperature) than the third.  And it is almost constantly being exported to Baffin Bay.
Title: Re: The 2017 melting season
Post by: Bill Fothergill on April 07, 2017, 08:38:49 PM
... I'll be posting the first poll in June, and I would kindly ask others not to open polls before that.

It's a crap shoot either way, but projections are more solid after the first phase of the melting season has passed (April-May-first week of June).

Yep, that's just the way the Sea Ice Prediction Network team see it as well.

https://www.arcus.org/sipn/sea-ice-outlook (https://www.arcus.org/sipn/sea-ice-outlook)

The SIPN people put out regularly updated summaries of the "predictions" they have received. These tend to kick off in June, with updates (i.e rethinks) getting aired, once in July and once in August. More details are available on the SIPN site.

A term that applies here is "decorrelation time". In layman's terms, and in the context of the September Arctic minimum, that basically means how far ahead does one see a good correlation between the current extent (or area, or volume - depends on your metric of choice) and that finally clocked up in September.

There are various papers available on this subject, and here is an example...

https://www.atmos.washington.edu/~bitz/Blanchard_etal2011.pdf (https://www.atmos.washington.edu/~bitz/Blanchard_etal2011.pdf)

Quoting from the Conclusion section of the above paper...

"We find that sea ice area at the summer minimum (September) is only significantly correlated with area in the previous two months, July and August, both in the model and observations."

Of course, some clown wrote an article on the Arctic Sea Ice Blog on that very subject in 2013.

http://neven1.typepad.com/blog/2013/06/problematic-predictions.html (http://neven1.typepad.com/blog/2013/06/problematic-predictions.html)

Title: Re: The 2017 melting season
Post by: Tigertown on April 07, 2017, 09:37:54 PM
NSIDC SIE 106 km2
2017,    03,  25,     14.073                             2017,    04,  01,     14.126
2017,    03,  26,     14.107                             2017,    04,  02,     14.143
2017,    03,  27,     14.169                             2017,    04,  03,     14.227
2017,    03,  28,     14.178                             2017,    04,  04,     14.209
2017,    03,  29,     14.178                             2017,    04,  05,     14.114
2017,    03,  30,     14.181                             2017,    04,  06,     14.040
2017,    03,  31,     14.172

Last day below 14 million               2017,    02,  12,     13.898
Title: Re: The 2017 melting season
Post by: seaicesailor on April 08, 2017, 12:07:42 AM
... I'll be posting the first poll in June, and I would kindly ask others not to open polls before that.

It's a crap shoot either way, but projections are more solid after the first phase of the melting season has passed (April-May-first week of June).
Yep, that's just the way the Sea Ice Prediction Network team see it as well.


But I wonder if at some point the correlation can go further into May, April,... like for example when there is not enough ice past the Winter.

Extreme unreal  case to make myself understand, if there be zero ice in March, there be zero ice in September.

Being more realistic, if volume available in April keeps decreasing until a moment the heat brought by a less than average warm season is enough to melt it all, the SIPN wont make sense anymore, or our polls :-( (the least of the problems in reality).
Title: Re: The 2017 melting season
Post by: dosibl on April 08, 2017, 12:16:24 AM
At this point in the season I'd expect volume to be the most informative feature for the minimum, I've been shying away from the area/extent graphs because I don't think they tell as much of the story for overall ice health at the end of the freeze.
Title: Re: The 2017 melting season
Post by: Tigertown on April 08, 2017, 02:44:45 AM
At this point in the season I'd expect volume to be the most informative feature for the minimum, I've been shying away from the area/extent graphs because I don't think they tell as much of the story for overall ice health at the end of the freeze.
A concentration graph would be good to see about right now. Wipneus has posted one in the past, though not lately, to my knowledge anyway.
Title: Re: The 2017 melting season
Post by: oren on April 08, 2017, 07:36:14 AM
The SIPN is right, onsidering that in the past few years all 3 metrics (extent, area, volume) were stable with random variability around March-April, thereby giving zero information. On the other hand, sis and dosibl are right, and this year has a very different volume. Will it matter come September? And will volume be low next winter as well? I am waiting anxiously for the answers.
Title: Re: The 2017 melting season
Post by: romett1 on April 08, 2017, 09:49:56 AM
Latest GFS anomalies (Climate Reanalyzer). Currently showing two low pressures next week over Bering Sea, high pressure (1,041) over Beaufort.
Image: low over Bering Sea on Wednesday (earth.nullschool).
Title: Re: The 2017 melting season
Post by: jai mitchell on April 08, 2017, 07:19:05 PM
just want to say, I sure miss A-Team.
Title: Re: The 2017 melting season
Post by: Lord M Vader on April 08, 2017, 07:26:47 PM
Any idea about A-Team is? And where is Frivoulouz? Haven't seen Sleepy here either for a while.
Title: Re: The 2017 melting season
Post by: Shared Humanity on April 08, 2017, 07:36:09 PM
Any idea about A-Team is? And where is Frivoulouz? Haven't seen Sleepy here either for a while.

All missed.
Title: Re: The 2017 melting season
Post by: oren on April 08, 2017, 08:28:24 PM
+1
Title: Re: The 2017 melting season
Post by: Tealight on April 08, 2017, 10:48:18 PM
Everyone who believes in patterns can expect another strong melting season. In my pan-Arctic AWP graphs the cumulative value follows the pattern: 2 strong melting seasons followed by 2 weak melting season and one average melting season before the cycle repeats. However the regional breakdown is very important for the minimum in September. A record high pan-Arctic value doesn't guarantee a new record minimum like 2016 has shown. At least 2017 seems to follow the pattern with a record high AWP to date.

Over longer periods all years shift towards a higher energy absorption. When I did the calculation for 1988 and 1992 they ended up at -50 kWh/m2 and make 2009(-20kWh/m2) or 2013(-13kWh/m2) look like strong melting seasons.

The Pattern
2007   strong
2008   weak
2009   weak
2010   average
2011   strong
2012   strong
2013   weak
2014   weak
2015   average
2016   strong
2017   (strong)
Title: Re: The 2017 melting season
Post by: Neven on April 08, 2017, 11:06:56 PM
Tealight, maybe a short explanation would be interesting for people who lurk. I'm guessing you calculate Albedo-Warming Potential by combining sea ice concentration with how much energy is soaked up by open water?

Hang on, it's all there on your website (https://sites.google.com/site/cryospherecomputing/warming-potential/project-description):

The Albedo-Warming Potential is an attempt to quantify the additional warming from a lower ice cover at the poles. At the moment these calculations don't include cloud cover, therefore it is called "Warming Potential" and not actual warming. However, over six-month weather tends to average out and warm areas correlate well with low ice extent in September. The basis of all calculations is a self-developed global surface radiation model and NSIDC Sea Ice Concentration data.

The results could be used as a basis for sea ice forecast models and an analysis tool for scientists in combination with wind maps and ice drift maps. The cumulative results also give a better view of the whole melting season than just one single value for the final September sea ice extent.

Global surface radiation model details:
The model calculates the incoming solar radiation reaching the surface per day per square meter for all latitudes between 40N and 90N (0.2 degree steps). Considered are solar zenith angles, the atmospheric reduction (Air mass), projection effect and water albedo for every 15min interval. See the Block Diagram below for details.

(https://docs.google.com/uc?id=0B5JYfcI0wFH6RGVTemgwQnB4djg&export=download)
Title: Re: The 2017 melting season
Post by: Tealight on April 08, 2017, 11:35:27 PM
Tealight, maybe a short explanation would be interesting for people who lurk. I'm guessing you calculate Albedo-Warming Potential by combining sea ice concentration with how much energy is soaked up by open water?

Hang on, it's all there on your website (https://sites.google.com/site/cryospherecomputing/warming-potential/project-description):

Thank you Neven. That's of course important to explain. I just spend too much time on it and know it by heart.

AWP also considers melt ponds mainly in May/June/July.
Title: Re: The 2017 melting season
Post by: johnm33 on April 08, 2017, 11:40:37 PM
+1
I can't believe he's lost interest, i thought/hoped he'd maybe start up his own show, an uninterrupted record of events, oh well.
Title: Re: The 2017 melting season
Post by: oren on April 09, 2017, 12:10:44 AM
Tealight, I personally don't believe in simplistic patterns like the one you mention, though I do believe 2017 will be a strong melting season. And I do also believe that AWP is extremely important. I have a gut feeling that the poor refreeze in autumn 2016 was very much related to the very high AWP throughout 2016.
Title: Re: The 2017 melting season
Post by: JayW on April 09, 2017, 12:18:42 AM
April 4-8

http://feeder.gina.alaska.edu/npp-gina-alaska-truecolor-images?search%5Bfeeds%5D%5B5%5D=1&search%5Bsensors%5D%5B3%5D=1 (http://feeder.gina.alaska.edu/npp-gina-alaska-truecolor-images?search%5Bfeeds%5D%5B5%5D=1&search%5Bsensors%5D%5B3%5D=1)
Title: Re: The 2017 melting season
Post by: Greenbelt on April 09, 2017, 03:33:23 AM
GFS and ECMWF continue to indicate a very strong storm in Asian North Pacific preceding a building big high pressure in the Arctic on the Pacific side. The Atlantic has been so active, but maybe the Pacific side is set to be very interesting in April.

(http://www.tropicaltidbits.com/analysis/models/gfs/2017040818/gfs_z500_mslp_nhem_22.png)
(http://www.tropicaltidbits.com/analysis/models/ecmwf/2017040812/ecmwf_z500_mslp_nhem_6.png)
Title: Re: The 2017 melting season
Post by: Darvince on April 09, 2017, 04:39:05 AM
Any idea about A-Team is? And where is Frivoulouz? Haven't seen Sleepy here either for a while.
A-Team was driven out by the rise in relentless off-topic posts in important threads like this one, and Sleepy deleted his account b/c of a disagreement about political posts.

Latest GFS goes bonkers with the Beaufort High:
(http://i.imgur.com/BkW9w5n.png)

In the GEFS it reaches a peak of 1037mb, and because of the way that Tropicaltidbits displays the highs, most of the members' peak pressure is probably higher than this because of varying time and location.
Title: Re: The 2017 melting season
Post by: DrTskoul on April 09, 2017, 05:38:04 AM
Well, with so many excitable followers it almost impossible not to stray off topic. Especially online where a sense of etiquette ia often missing. Anyway, a little patience never harms.

On topic. An amoeba  of lows is swallowing a high...beaufort is on for some sunny skies...
Title: Re: The 2017 melting season
Post by: Tigertown on April 09, 2017, 05:58:55 AM
An interesting development on Uni-Bremen concentration.
Left to right 6th-8th April
(http://)
Title: Re: The 2017 melting season
Post by: Jim Hunt on April 09, 2017, 09:16:00 AM
Open water (as far as AMSR2 is concerned) is appearing in the Beaufort Sea at almost exactly the same time as last year:

http://GreatWhiteCon.info/2017/04/facts-about-the-arctic-in-april-2017/#comment-221357 (http://GreatWhiteCon.info/2017/04/facts-about-the-arctic-in-april-2017/#comment-221357)
Title: Re: The 2017 melting season
Post by: romett1 on April 09, 2017, 10:36:36 AM
Latest GFS anomalies (Climate Reanalyzer). Second storm over Bering Sea is more powerful than first and entering the Arctic over Chukchi Peninsula next weekend. Therefore anomalies +20 °C over Chukchi Sea and ESS next weekend and high over Beaufort (1,047). Image: temp anomaly forecast for Sunday, Apr 16.
Title: Re: The 2017 melting season
Post by: romett1 on April 09, 2017, 11:28:23 AM
Open water (as far as AMSR2 is concerned) is appearing in the Beaufort Sea at almost exactly the same time as last year:


Almost same level as June 25th 2013.
Title: Re: The 2017 melting season
Post by: oren on April 09, 2017, 12:02:11 PM
The (relatively) lower temps are showing up on the DMI chart, nearing the mean for only the second time this year.
Title: Re: The 2017 melting season
Post by: Neven on April 09, 2017, 12:14:58 PM
Those storms in the North Pacific are going to cause even larger drops in the Okhotsk and Bering. The ice in the Okhotsk has already been pushed away from the coast quite some ways, which is rather uncommon for this time of year (https://sites.google.com/site/arcticseaicegraphs/concentration-maps/sic0413), in the past decade at least (with the possible exception of 2014).

And then that high over the Beaufort Sea is going to pull away the ice from the American coast (thanks for that animation, JayW).

So, given the low temperatures and the situation on the Atlantic side of the Arctic, the rate of extent decrease is going to remain slow for a while, but there's actually going to be a lot of damage on the Pacific side of the Arctic.
Title: Re: The 2017 melting season
Post by: Neven on April 09, 2017, 12:19:58 PM
And NH snow cover seems to be lowest right now:
Title: Re: The 2017 melting season
Post by: iceman on April 09, 2017, 12:55:05 PM
   ....
AWP also considers melt ponds mainly in May/June/July.
Counting them as additional open-water equivalent?  Or do you factor in any lensing effect, transmitting proportionately more insolation into the water beneath the ice ponds? 
     I have not seen any quantification, but if the amount is material, its heat signal could persist through the minimum and even early refreeze season.  That would corroborate Oren's "gut feeling."

Tealight, I personally don't believe in simplistic patterns like the one you mention, though I do believe 2017 will be a strong melting season. And I do also believe that AWP is extremely important. I have a gut feeling that the poor refreeze in autumn 2016 was very much related to the very high AWP throughout 2016.
Title: Re: The 2017 melting season
Post by: JayW on April 09, 2017, 01:14:42 PM
A closer look shows the openings in the Beaufort are freezing over fairly quickly, not really unexpected this time of year, in my humble opinion.

Amundsen gulf on the right.

http://feeder.gina.alaska.edu (http://feeder.gina.alaska.edu)
Title: Re: The 2017 melting season
Post by: Jim Hunt on April 09, 2017, 01:28:14 PM
A closer look shows the openings in the Beaufort are freezing over fairly quickly, not really unexpected this time of year, in my humble opinion.

IMHO too. Hence my "as far as AMSR2 is concerned" proviso, and the "in 2016 the early open water mostly refroze over the next couple of weeks" at my link.
Title: Re: The 2017 melting season
Post by: JayW on April 09, 2017, 02:51:16 PM
A closer look shows the openings in the Beaufort are freezing over fairly quickly, not really unexpected this time of year, in my humble opinion.


IMHO too. Hence my "as far as AMSR2 is concerned" proviso, and the "in 2016 the early open water mostly refroze over the next couple of weeks" at my link.


I'm actually finding the area extending NW from the coast of Alaska west of Utqiagvik interesting.  Looks like an "alley" of rubble.

Just bunch of back and forth in the Bering Strait.

Alaska in lower left corner.

http://feeder.gina.alaska.edu (http://feeder.gina.alaska.edu)
Title: Re: The 2017 melting season
Post by: Shared Humanity on April 09, 2017, 02:55:37 PM
Well, with so many excitable followers it almost impossible not to stray off topic. Especially online where a sense of etiquette ia often missing. Anyway, a little patience never harms.

On topic. An amoeba  of lows is swallowing a high...beaufort is on for some sunny skies...

I believe in patience as well which means we should insist immediately and patiently to the off topic commenter that they should take it to another thread. I will watch myself more closely as well. We all need to model this behavior for newcomers.
Title: Re: The 2017 melting season
Post by: Shared Humanity on April 09, 2017, 02:58:15 PM
Open water (as far as AMSR2 is concerned) is appearing in the Beaufort Sea at almost exactly the same time as last year:

[url]http://GreatWhiteCon.info/2017/04/facts-about-the-arctic-in-april-2017/#comment-221357[/url] ([url]http://GreatWhiteCon.info/2017/04/facts-about-the-arctic-in-april-2017/#comment-221357[/url])


These SIA charts are great for tracking the melt season in different areas of the Arctic. I expect this year will continue to track 2016 and end up, essentially ice free like last year.
Title: Re: The 2017 melting season
Post by: Tor Bejnar on April 09, 2017, 03:04:42 PM
The (relatively) lower temps are showing up on the DMI chart, nearing the mean for only the second time this year.
also, 2nd time since about day 255 last year (mid-Sept. 2016).
Title: Re: The 2017 melting season
Post by: Shared Humanity on April 09, 2017, 03:11:27 PM
If you look at all of the charts for these areas, 2017 looks fairly unremarkable when compared to the performance of recent years and considering the current weakened state of the ice. (The Sea of Okhotsk and the Bering the only exceptions.)

https://14adebb0-a-62cb3a1a-s-sites.googlegroups.com/site/arctischepinguin/home/amsr2/grf/amsr2-extent-regional.png?attachauth=ANoY7cr3sTwdvxVHuIsm6SWW02mnEU9bViizovuYEhYIcsJDY-6_KIMmFh4UYZ1eSiff2IlyJfhjJflKPWYE_ymwuFRXQFe_ZEKLUsbPHx1EdkeYznlVjk4BuPWPBngVeUqiAD43Y5GZ0nP-mo58uHYqI3P2RCiLuWN1pNWkPWmDvuagoyqu0VFjBbNseRac7q5GOI5iaT-Pa7gndAkkEFlcBGU763yoXMRXRvyGkyL0X6aNxOXVWgWtjhP_FQmag7Lk4IhEOnQ_&attredirects=0 (https://14adebb0-a-62cb3a1a-s-sites.googlegroups.com/site/arctischepinguin/home/amsr2/grf/amsr2-extent-regional.png?attachauth=ANoY7cr3sTwdvxVHuIsm6SWW02mnEU9bViizovuYEhYIcsJDY-6_KIMmFh4UYZ1eSiff2IlyJfhjJflKPWYE_ymwuFRXQFe_ZEKLUsbPHx1EdkeYznlVjk4BuPWPBngVeUqiAD43Y5GZ0nP-mo58uHYqI3P2RCiLuWN1pNWkPWmDvuagoyqu0VFjBbNseRac7q5GOI5iaT-Pa7gndAkkEFlcBGU763yoXMRXRvyGkyL0X6aNxOXVWgWtjhP_FQmag7Lk4IhEOnQ_&attredirects=0)

What does stand out for 2017 is the average thickness of the ice which should reveal itself early this year with rapid drops in SIE and SIA in the seas with anomalously thin ice compared to even last year. The Beaufort is one of these.

http://psc.apl.washington.edu/wordpress/wp-content/uploads/schweiger/ice_volume/Bpiomas_plot_daily_heff.2sst.png (http://psc.apl.washington.edu/wordpress/wp-content/uploads/schweiger/ice_volume/Bpiomas_plot_daily_heff.2sst.png)
Title: Re: The 2017 melting season
Post by: Darvince on April 09, 2017, 08:42:08 PM
These SIA charts are great for tracking the melt season in different areas of the Arctic. I expect this year will continue to track 2016 and end up, essentially ice free like last year.

By pixel counting on the image uploaded below of NSIDC Charctic's 2016 September 6th, and removing spurious ice, (for extent, I don't know how I would do that with area), only 50.70% of the Arctic Ocean was free of ice (6,416 pixels of water vs 6,238 pixels of ice) at the 2016 minimum. However, using Wipneus's compactness graphs (https://sites.google.com/site/arctischepinguin/home/amsr2/grf/amsr2-compact-compare.png), we can multiply the area of ice by 0.5833... (using the data for the 6th) (edit uploaded below) and obtain the value for total sea ice cover of 3,638 and 5/6 pixels. Then, using a little bit of math, we obtain the value of 9015 and 1/6 pixels of water, and find the total Arctic Ocean water area to take up 71.24% of the basin. That's still 28.76% ice, which to me does not seem like essentially ice free. Perhaps once we get into the single digits we could talk about it being essentially ice free, however.
Title: Re: The 2017 melting season
Post by: Shared Humanity on April 09, 2017, 09:03:52 PM
I was responding to Jim Hunt's graph about the Beaufort which was essentially ice free last year.
Title: Re: The 2017 melting season
Post by: Darvince on April 09, 2017, 10:51:12 PM
I was responding to Jim Hunt's graph about the Beaufort which was essentially ice free last year.
Ah, yes, the Beaufort was definitely in the single digits at last year's minimum ;D
Title: Re: The 2017 melting season
Post by: romett1 on April 10, 2017, 09:24:38 AM
Latest GFS anomalies (Climate Reanalyzer). Sort of interesting situation - mainland temperatures remain low, but Pacific side, Chukchi, ESS, Laptev and North Pole significantly warmer than usual.
Title: Re: The 2017 melting season
Post by: BornFromTheVoid on April 10, 2017, 11:48:09 AM
Latest GFS anomalies (Climate Reanalyzer). Sort of interesting situation - mainland temperatures remain low, but Pacific side, Chukchi, ESS, Laptev and North Pole significantly warmer than usual.

Sorry if this has been answered before, but are the values there for surface air temps? How are they calculated? Cheers
Title: Re: The 2017 melting season
Post by: romett1 on April 10, 2017, 12:14:53 PM

Sorry if this has been answered before, but are the values there for surface air temps? How are they calculated? Cheers

They are surface air (2m) temps for area 65°N - 90°N. That includes for example northern part of Alaska, Northern Canada, Greenland, Svalbard, northern Scandinavia and northern part of Russia.
There are 4 estimates per day, 6-hour difference, so I calculate daily average. Days 5-7 have been rather incorrect, as actual temperatures turned out higher.
Title: Re: The 2017 melting season
Post by: BornFromTheVoid on April 10, 2017, 12:34:08 PM
They are surface air (2m) temps for area 65°N - 90°N. That includes for example northern part of Alaska, Northern Canada, Greenland, Svalbard, northern Scandinavia and northern part of Russia.
There are 4 estimates per day, 6-hour difference, so I calculate daily average. Days 5-7 have been rather incorrect, as actual temperatures turned out higher.

Thanks for that. I wonder if it might be better to use 925hPa or maybe 850hPa temperatures now that we're in the melt season? The surface air temps will hold close to 0C regardless of heat input over much of the Arctic for the next few months, so it may not be of much use
Title: Re: The 2017 melting season
Post by: JayW on April 10, 2017, 01:29:27 PM
April 6-9

Used the "landcover" band to better show the clouds forming off the open water around Alaska.

http://feeder.gina.alaska.edu/npp-gina-alaska-landcover-images?page=3&search%5Bfeeds%5D%5B6%5D=1&search%5Bsensors%5D%5B3%5D=1 (http://feeder.gina.alaska.edu/npp-gina-alaska-landcover-images?page=3&search%5Bfeeds%5D%5B6%5D=1&search%5Bsensors%5D%5B3%5D=1)

Title: Re: The 2017 melting season
Post by: Shared Humanity on April 10, 2017, 02:39:40 PM
They are surface air (2m) temps for area 65°N - 90°N. That includes for example northern part of Alaska, Northern Canada, Greenland, Svalbard, northern Scandinavia and northern part of Russia.
There are 4 estimates per day, 6-hour difference, so I calculate daily average. Days 5-7 have been rather incorrect, as actual temperatures turned out higher.

Thanks for that. I wonder if it might be better to use 925hPa or maybe 850hPa temperatures now that we're in the melt season? The surface air temps will hold close to 0C regardless of heat input over much of the Arctic for the next few months, so it may not be of much use

Both might be useful for different reasons. 2m anomalies will track the disappearance of sea ice and end of melt in a specific area and we will be able to witness the dramatic impact on surface temperatures. 925hPa will provide us with a more accurate assessment of intrusion of warm air masses.
Title: Re: The 2017 melting season
Post by: Csnavywx on April 10, 2017, 03:53:03 PM
Surface temps over the Arctic Ocean itself work just fine until about early/mid-May. After that, 925+850 temps are better. 850 temps also work better in the long range since they tend to be just above the boundary layer, where flow is smoother and easier to model (closer to "ideal" flow -- much the same reason 500mb height and height anomalies are used in the long range).
Title: Re: The 2017 melting season
Post by: jai mitchell on April 10, 2017, 09:04:26 PM
not sure if this would be the best thread for this post but wanted to note that the March northern hemisphere snow cover anomaly is nearly tied for its lowest in the series.

Title: Re: The 2017 melting season
Post by: Neven on April 10, 2017, 09:16:16 PM
not sure if this would be the best thread for this post but wanted to note that the March northern hemisphere snow cover anomaly is nearly tied for its lowest in the series.

That was last year, Jai. This past March it was almost dead average, which makes the bar difficult to see.

Right now, snow cover is lowest for the past decade (see top of this page), but not by a lot.
Title: Re: The 2017 melting season
Post by: jai mitchell on April 10, 2017, 11:58:55 PM
ahhh yes thanks, it was so close to average I missed the mark!  wouldn't be the first time!
Title: Re: The 2017 melting season
Post by: Neven on April 11, 2017, 12:20:34 AM
I checked that graph two days ago and wondered why this year's results for March still weren't in. Until I saw that tiny green speck.  ;D
Title: Re: The 2017 melting season
Post by: Tigertown on April 11, 2017, 01:36:59 AM
NSIDC SIE 106 km2
2017,    03,  25,     14.073                             2017,    04,  01,     14.126
2017,    03,  26,     14.107                             2017,    04,  02,     14.143
2017,    03,  27,     14.169                             2017,    04,  03,     14.227
2017,    03,  28,     14.178                             2017,    04,  04,     14.209
2017,    03,  29,     14.178                             2017,    04,  05,     14.114
2017,    03,  30,     14.181                             2017,    04,  06,     14.040
2017,    03,  31,     14.172

Last day below 14 million               2017,    02,  12,     13.898
Going down now:
2017,    04,  08,     13.993
2017,    04,  09,     13.875
Title: Re: The 2017 melting season
Post by: Shared Humanity on April 11, 2017, 01:51:17 AM
Amazing that it went from average to lowest in a single month.
Title: Re: The 2017 melting season
Post by: Cid_Yama on April 11, 2017, 03:58:55 AM
Uni-Bremen AMSR-2 site has been down over 16 hrs.  On top of losing Lance, I'm beginning to worry about our eyes getting put out.

Losing Lance-MODIS is devastating.

What if, I know this is paranoid, but what if instead of discussing how to cut emissions, they've been discussing how to deal with what is known by the public when/as it happens.

I don't want to be blinded.

I mean what if they came to some agreement that when it gets bad, everything goes dark?

If I were a politician, making sure everyone shows up for work Monday morning, and pays their bills, would be the highest priority.

I mean if I were totally morally corrupt like them.  They may see it as the greatest good.   
Title: Re: The 2017 melting season
Post by: Tigertown on April 11, 2017, 05:21:06 AM
@Cid
It might be hard for them to hide when people on the North-East coast of the U.S. start reporting icebergs floating by.

In the meantime, I have been depending on this:
www.polarview.aq/sic/arctic/ (http://www.polarview.aq/sic/arctic/)
Title: Re: The 2017 melting season
Post by: Neven on April 11, 2017, 06:49:55 AM
Uni-Bremen AMSR-2 site has been down over 16 hrs.  On top of losing Lance, I'm beginning to worry about our eyes getting put out.

Losing Lance-MODIS is devastating.

What happened to LANCE-MODIS?
Title: Re: The 2017 melting season
Post by: silkman on April 11, 2017, 09:37:02 AM
I don't know but it's been like this for a few weeks:

https://lance.modaps.eosdis.nasa.gov/imagery/subsets/?mosaic=Arctic..terra.4km

It was my first port of call over breakfast. Much missed if it's not restored.
Title: Re: The 2017 melting season
Post by: Cid_Yama on April 11, 2017, 09:38:09 AM
Decided to try to find out.  Apparently they have replaced it with a new product called Worldview.

   https://worldview.earthdata.nasa.gov/?p=arctic&l=VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor,Reference_Labels(hidden),Reference_Features(hidden),Coastlines&t=2017-04-09&z=3&v=-5595136,-2551808,5595136,2551808


Thank God!  Didn't want to have to go through the summer without being able to see.  I guess one shouldn't assume. 

Title: Re: The 2017 melting season
Post by: pauldry600 on April 11, 2017, 11:59:31 AM
Your right to be paranoid Cid.

I know a certain person who lives in a house that is white who wouldnt mind if all the Arctic Sea Ice and Polarviews just got inaccessible all of a sudden....and its not Santa

@Tigertown ... i love that site
Title: Re: The 2017 melting season
Post by: Gray-Wolf on April 11, 2017, 12:16:11 PM
not sure if this would be the best thread for this post but wanted to note that the March northern hemisphere snow cover anomaly is nearly tied for its lowest in the series.

That was last year, Jai. This past March it was almost dead average, which makes the bar difficult to see.

Right now, snow cover is lowest for the past decade (see top of this page), but not by a lot.

I'm very keen to find out how w.Siberia, which took the WACCy hit in October of 7 months of snow in that month, melts out? I see no 'positive anom' over the region any more so it is starting to look like whatever WACC throws at the north it is not impacting the following melt season?

I worry that such snow cover ,early in re-freeze, protects the ground below from the rigours of an Arctic winter and so ,come melt ,leaves it prone to further degradation ( as we are seeing across Yamal?).
Title: Re: The 2017 melting season
Post by: meddoc on April 11, 2017, 01:17:57 PM
Your right to be paranoid Cid.

I know a certain person who lives in a house that is white who wouldnt mind if all the Arctic Sea Ice and Polarviews just got inaccessible all of a sudden....and its not Santa

@Tigertown ... i love that site


The guy in Whiskey Hotel is just a Puppet/ Teleprompter Reader.
Ask Ed Snowden, Wikileaks or JFK if You have any doubts.

This one still online:

http://www.arctic.io/explorer/ (http://www.arctic.io/explorer/)
Title: Re: The 2017 melting season
Post by: romett1 on April 11, 2017, 01:37:41 PM
Meanwhile average wind speed for the next 5 days. I'm wondering how much ice will survive this ride over Bering Sea.
Title: Re: The 2017 melting season
Post by: pauldry600 on April 11, 2017, 01:58:46 PM
Not sure but the wind speeds in Ireland are the same today and we are surviving :-X
Title: Re: The 2017 melting season
Post by: Tigertown on April 11, 2017, 03:21:56 PM
Uni-Bremen is back up.
(http://)
Title: Re: The 2017 melting season
Post by: Tigertown on April 11, 2017, 04:13:50 PM
Iceberg season in the North Atlantic is about two months ahead of schedule. Although these are not from sea ice, this article shows how the earliness is connected to sea ice reduction.

https://weather.com/news/climate/news/iceberg-threat-arctic-shipping-lanes?cm_ven=FB_WX_EC_41017_5&utm_medium=email&utm_source=website&cm_ven=Email&cm_cat=

The wild start to iceberg season fits with a pattern of rapid Arctic change that could alter access to the region. The sea ice minimum, usually hit in September, has decreased by more than 13 percent a decade since the late 1970s. That’s largely driven by the warm air and water invading the region due to climate change.

The region just had its third year in a row of record low winter sea ice and repeated bouts of warm air helping melt out ice. Warm ocean waters are also responsible for making the eastern Arctic Ocean more like the Atlantic. That could further shrink icepack, particularly in summer, allowing for easy navigation.

 Icebergs in the North Atlantic typically come from calving events off of Greenland’s glaciers, which are quickly melting due to rising temperatures.
Title: Re: The 2017 melting season
Post by: JimboOmega on April 11, 2017, 05:49:44 PM
Uni-Bremen is back up.
(http://)

What's happening in the Hudson? Melt ponds? Is that atypical for this time of year?
Title: Re: The 2017 melting season
Post by: Tigertown on April 11, 2017, 06:29:59 PM
Uni-Bremen is back up.
(http://)

What's happening in the Hudson? Melt ponds? Is that atypical for this time of year?
The ice there didn't really get to thicken up much last winter. 2014, 2015, and 2016 all show it in a lot better shape at this point in the year.
Title: Re: The 2017 melting season
Post by: Random_Weather on April 11, 2017, 06:35:29 PM
I  think it was melt ponds, between 9 and 10th of April, there was a strong warm air advection above the hudson, perhaps it was enough for melt ponds, but today its replaced by cold air, so in the nxt update, it should be gone, if not, it was no melt ponds, more wind driven divergence of the sea ice there.
Title: Re: The 2017 melting season
Post by: Cid_Yama on April 11, 2017, 07:33:06 PM
Those are not melt ponds.
Title: Re: The 2017 melting season
Post by: rboyd on April 11, 2017, 10:59:24 PM
Big positive anomalies coming back to the Arctic Basin, Kara and Barents Seas:
Title: Re: The 2017 melting season
Post by: JimboOmega on April 12, 2017, 12:00:24 AM
Big positive anomalies coming back to the Arctic Basin, Kara and Barents Seas:

Even more crazy when you look at the temps themselves being forecast... since the baseline is rising rapidly this time of year.

The center of the patch in the central arctic is forecast to be above 0 C!
Title: Re: The 2017 melting season
Post by: epiphyte on April 12, 2017, 08:11:32 AM
I wanted to relate that the worldview "Sea Ice Brightness Temperature" overlays make it all very real, to me at least, since they cut through the darkness and clouds to make it easy to see actual day-to-day ice migration across the arctic.

For what it's worth I used the above to make an amateurish video comparison of this year vs last for the Greenland/Atlantic quadrant for Mar 01 - Apr 11. It's at:

https://youtu.be/Yf73zutgeDU

...Don't know if it will have the same impact on others as it did on me, but IMO the main takeaway is that if we thought that the ice was a) too warm and b) unprecedentedly mobile and c) headed in the wrong direction in 2016, then hold on to your hats - because so far, at least, 2017 looks much worse.
Title: Re: The 2017 melting season
Post by: Tigertown on April 12, 2017, 08:21:59 AM
Good job on the video. Yes, you can tell the difference.
Title: Re: The 2017 melting season
Post by: Jim Hunt on April 12, 2017, 08:49:37 AM
The latest Arctic Sea Ice News is out:

http://GreatWhiteCon.info/2017/04/facts-about-the-arctic-in-april-2017/#Apr-12 (http://GreatWhiteCon.info/2017/04/facts-about-the-arctic-in-april-2017/#Apr-12)

Apart from confirming that March monthly extent was lowest in the satellite record there's also this:

New work by an international team led by Igor Polyakov of the University of Alaska Fairbanks provides strong evidence that Atlantic layer heat is now playing a prominent role in reducing winter ice formation in the Eurasian Basin, which is manifested as more summer ice loss. According to their analysis, the ice loss due to the influence of Atlantic layer heat is comparable in magnitude to the top down forcing by the atmosphere.

Title: Re: The 2017 melting season
Post by: Jim Hunt on April 12, 2017, 08:52:02 AM
Apparently they have replaced it with a new product called Worldview.


Worldview isn't new. It's been around for years:

http://econnexus.org/a-new-world-view-from-nasa/ (http://econnexus.org/a-new-world-view-from-nasa/)
Title: Re: The 2017 melting season
Post by: jdallen on April 12, 2017, 09:02:53 AM
The latest Arctic Sea Ice News is out:

<snippage>

New work by an international team led by Igor Polyakov of the University of Alaska Fairbanks provides strong evidence that Atlantic layer heat is now playing a prominent role in reducing winter ice formation in the Eurasian Basin, which is manifested as more summer ice loss. According to their analysis, the ice loss due to the influence of Atlantic layer heat is comparable in magnitude to the top down forcing by the atmosphere.

This is an unexpected and very bad finding.
Title: Re: The 2017 melting season
Post by: seaicesailor on April 12, 2017, 11:40:41 AM
I wanted to relate that the worldview "Sea Ice Brightness Temperature" overlays make it all very real, to me at least, since they cut through the darkness and clouds to make it easy to see actual day-to-day ice migration across the arctic.

For what it's worth I used the above to make an amateurish video comparison of this year vs last for the Greenland/Atlantic quadrant for Mar 01 - Apr 11. It's at:

https://youtu.be/Yf73zutgeDU

...Don't know if it will have the same impact on others as it did on me, but IMO the main takeaway is that if we thought that the ice was a) too warm and b) unprecedentedly mobile and c) headed in the wrong direction in 2016, then hold on to your hats - because so far, at least, 2017 looks much worse.
Nice video, clearly reflects Fram export amount has been on the high side and a lot of ice is now being stationed in danger zone (anywhere around Svalbard, and  Greenland sea)
What the video cannot reflect is that the proportion of outgoing ice being more than 2 years old is higher this year than the past. Perhaps why it is surviving stationed near Svalbard for long time while last year it just vanished miles north of the islands. Sadly, because the overall MYI amount is supposed to be much smaller than last year's.
Title: Re: The 2017 melting season
Post by: Meirion on April 12, 2017, 02:07:37 PM
If you click though the AARI map week by week over the last few months you'll see how much MYI has gone out the Fram - it's a lot

http://www.aari.ru/odata/_d0015.php?lang=1 (http://www.aari.ru/odata/_d0015.php?lang=1)

Title: Re: The 2017 melting season
Post by: Gray-Wolf on April 12, 2017, 02:37:07 PM

This is an unexpected and very bad finding.

But nothing that we haven't been mooting in here for years?

Barentsz/Kara have been seeing ice free conditions since the start of the noughties ( why Jen Francis focused her studies of the atmosphere above there?) so the old , protective, Halocline must surely be lost there now ( with just a 'normal' Halocline setting up under any ice formed each winter?). The loss of this distinct layer removes the thing that forced Atlantic water to take a dive and so it now happily trundles on at the surface?

This will ( has?) push ever poleward from our ( Atlantic?) side of the basin making re-freeze ever more hopeless and providing no obstacle to any ice with a Fram death wish ( as we have been seeing?).

I do not know how we are all coping? After years of warning folk what might be about to happen not only are we sat watching it happen but the folk we were telling didn't appear to believe us and are now acting all shocked that we are where we are! Even the MSM speak of an ice free basin soon!
Title: Re: The 2017 melting season
Post by: Tigertown on April 12, 2017, 03:02:35 PM
@Meirion
Very good link. I bookmarked it and recommend doing so.
Title: Re: The 2017 melting season
Post by: Sarat on April 12, 2017, 09:02:53 PM
Looks like Beaufort is starting to open up...
Title: Re: The 2017 melting season
Post by: Neven on April 12, 2017, 09:05:25 PM
Given the forecast, we can expect more of that. I'll try and make an updated animation.

Edit: I still had the template from last year:
Title: Re: The 2017 melting season
Post by: Istari on April 12, 2017, 09:22:32 PM

This is an unexpected and very bad finding.

But nothing that we haven't been mooting in here for years?

Barentsz/Kara have been seeing ice free conditions since the start of the noughties ( why Jen Francis focused her studies of the atmosphere above there?) so the old , protective, Halocline must surely be lost there now ( with just a 'normal' Halocline setting up under any ice formed each winter?). The loss of this distinct layer removes the thing that forced Atlantic water to take a dive and so it now happily trundles on at the surface?

This will ( has?) push ever poleward from our ( Atlantic?) side of the basin making re-freeze ever more hopeless and providing no obstacle to any ice with a Fram death wish ( as we have been seeing?).

I do not know how we are all coping? After years of warning folk what might be about to happen not only are we sat watching it happen but the folk we were telling didn't appear to believe us and are now acting all shocked that we are where we are! Even the MSM speak of an ice free basin soon!

The problem is that we are risen Monkeys, not fallen Angel's... we don't got a feeling of thing that move outside a few years horizon... we need math for that, and so few of us really gets that ....
and right now the US are controlled by people that think the earth are 6000 years old, so what do you expect ?
This been and will be a lost course, if we are lucky a few humans survive and they remember why it went so wrong...
Title: Re: The 2017 melting season
Post by: Sarat on April 12, 2017, 09:28:20 PM
Thank you Neven!

Here is a Jim's video from last year for comparison: https://youtu.be/hHf7Raxs5rM

Looks like it was lingering back and fourth until early-mid April and then really started opening.
Title: Re: The 2017 melting season
Post by: jdallen on April 13, 2017, 01:05:43 AM
Given the forecast, we can expect more of that. I'll try and make an updated animation.

Edit: I still had the template from last year:
2017 Beaufort looks to be trying mightily to catch up with 2016's open water.  It becomes more clear looking at it in Worldview, where you can see in particular just how shattered the ice is.  There may be more coverage than last year, but it is not robust. The Amundsen Gulf in particular has disintegrated into a bowl of ice cubes.
Title: Re: The 2017 melting season
Post by: seaicesailor on April 13, 2017, 01:21:34 AM
Given the forecast, we can expect more of that. I'll try and make an updated animation.

Edit: I still had the template from last year:
2017 Beaufort looks to be trying mightily to catch up with 2016's open water.  It becomes more clear looking at it in Worldview, where you can see in particular just how shattered the ice is.  There may be more coverage than last year, but it is not robust. The Amundsen Gulf in particular has disintegrated into a bowl of ice cubes.
Yes and given that the high is going to strengthen and stay around 1050 hpa for three days, we'll definitively have material for animations.
Image from Tropicaltidbits ECMWF last run, forecast +72h
Title: Re: The 2017 melting season
Post by: seaicesailor on April 13, 2017, 01:33:49 AM
And starting with the ACNFS Hycom drift prediction from the 13th to 17th. The clockwise drift starting to look like a textbook Arctic drift map, something not seen much in all past winter.
Ice might detach even further from Amundsen bay Gulf as well
Title: Re: The 2017 melting season
Post by: Michael Hauber on April 13, 2017, 01:42:47 AM
New work by an international team led by Igor Polyakov of the University of Alaska Fairbanks provides strong evidence that Atlantic layer heat is now playing a prominent role in reducing winter ice formation in the Eurasian Basin, which is manifested as more summer ice loss. According to their analysis, the ice loss due to the influence of Atlantic layer heat is comparable in magnitude to the top down forcing by the atmosphere.


link to paper (http://science.sciencemag.org/content/early/2017/04/05/science.aai8204.full)

Note that this statement does not apply to the Arctic as a whole, but to a region referred to in the study as the Eastern European Basin, which is very roughly equivelant to the Laptev Sea area.

An interesting bit also is that the heat flow from the Atlantic peaked in 2007/2008 and has decreased slightly since.
Title: Re: The 2017 melting season
Post by: Adam Ash on April 13, 2017, 05:12:51 AM
And starting with the ACNFS Hycom drift prediction from the 13th to 17th. The clockwise drift starting to look like a textbook Arctic drift map, something not seen much in all past winter.
Ice might detach even further from Amundsen bay Gulf as well

Gosh those vectors are long!  The ice movement seems to be virtually unrestrained by any cohesion in the pack.  Any sustained blow from north towards the CAA, Nares or Barents will just shove already-chewed up ice into the oven.
Title: Re: The 2017 melting season
Post by: Neven on April 13, 2017, 08:15:29 AM
An interesting bit also is that the heat flow from the Atlantic peaked in 2007/2008 and has decreased slightly since.

Where does the time period end?
Title: Re: The 2017 melting season
Post by: romett1 on April 13, 2017, 09:27:16 AM
Big positive anomalies coming back to the Arctic Basin, Kara and Barents Seas:

Indeed, high positive temp anomalies over Arctic Ocean are back. Latest forecast, Apr 14 - Apr 20 (Climate Reanalyzer).
Title: Re: The 2017 melting season
Post by: Bill Fothergill on April 13, 2017, 11:05:43 AM
...  Amundsen bay Gulf ...

Yep, that's definitely the kind of typo to avoid when using SatNav.

 ;)
Title: Re: The 2017 melting season
Post by: Neven on April 13, 2017, 02:22:17 PM
I've asked why the LANCE-MODIS Arctic Mosaic isn't being updated, and received a swift reply:

We are in the process of making a required Operating System upgrade on our web server and some of the imagery is not available yet.

This gives us an opportunity to say that we are encouraging Rapid Response subset users with good internet bandwidth to consider using our Worldview web client for accessing imagery.  Here is a link to Worldview:

[url]https://worldview.earthdata.nasa.gov/[/url] ([url]https://worldview.earthdata.nasa.gov/[/url])

To access the polar view, click on the "globe" icon in the upper right corner and select "Arctic" or "Antarctic".  Note that the projections used by GIBS differ from those used by the old Rapid Response mosaics.

The Corrected Reflectance imagery is identical to that in Rapid Response but Worldview has many more imagery layers available, including other sensors in addition to MODIS.  The Worldview imagery goes back to 8 May 2012 for most layers.  We are in the process of generating imagery for the entire MODIS record which should be completed in 6-18 months. Additional historical imagery from other sensors is also planned.

In addition, all the imagery in Worldview is also available as a Web Map Tile Service (WMTS) which can be accessed in a variety of ways.  More details on the imagery and access methods are available here:

[url]http://earthdata.nasa.gov/gibs[/url] ([url]http://earthdata.nasa.gov/gibs[/url])

Let me know if you have any further questions.

We will let you know when the subsets imagery is restored.
Title: Re: The 2017 melting season
Post by: seaicesailor on April 13, 2017, 02:28:23 PM
And starting with the ACNFS Hycom drift prediction from the 13th to 17th. The clockwise drift starting to look like a textbook Arctic drift map, something not seen much in all past winter.
Ice might detach even further from Amundsen bay Gulf as well

Gosh those vectors are long!  The ice movement seems to be virtually unrestrained by any cohesion in the pack.  Any sustained blow from north towards the CAA, Nares or Barents will just shove already-chewed up ice into the oven.
Adam,
I should add the link to ACNFS page so that anybody can see the legend of color and the corresponding speed for a given arrow size, I am careless and just crop out without including them
https://www7320.nrlssc.navy.mil/hycomARC/arctic.html

But to give an idea the darkest red is 30 cm/s, 25 km/day approx, so if a region has sustained drift of that intensity for four days, I know gaps of order of 100 km wide are to appear (or existing ones widening up by as much) near the coasts of Alaska. Perhaps 40 km, perhaps 120 km, but not 10 km, not 200 km. I would not look at the arrows strict sense as if they indicate real displacement, but I just make that sort of mental rough calculation.
so, the Beaufort sea is gonna be in deep in May.
Title: Re: The 2017 melting season
Post by: iceman on April 13, 2017, 04:37:29 PM
Various comments above on Beaufort, but the likely opening this coming week in Chukchi would be quite a rarity for April.  Considerable insolation potential there too, if it holds for any length of time.
Title: Re: The 2017 melting season
Post by: Neven on April 14, 2017, 12:25:21 AM
Various comments above on Beaufort, but the likely opening this coming week in Chukchi would be quite a rarity for April.  Considerable insolation potential there too, if it holds for any length of time.

Yes, the forecast is quite amazing. Below is the ECMWF forecast from Tropical Tidbits for the coming 8 days. 1041-1046-1049-1049-1044-1042-1038-1036 hPa are pressures not to be sniffed at. So, expect a lot of ice pulling away from coasts in the Beaufort and Chukchi Seas. And then we'll have to see whether the ice will be pushed back again and/or whether there still is some refreeze possible (which would be entirely cosmetic, of course).
Title: Re: The 2017 melting season
Post by: Adam Ash on April 14, 2017, 08:06:13 AM
...
Gosh those vectors are long! ....
Adam,
I should add the link to ACNFS page so that anybody can see the legend...
so, the Beaufort sea is gonna be in deep in May.

Thanks SeaIce!  I had figured the vectors were an indication of velocity not distance.  Even 25 km a day is still a pretty step - especially when it is in a direction which is not conducive to the longevity of the ice.  My main concern was that the chart seemed to show that the ice pack is no longer offering any significant resistance to wind-induced motion beyond what a bit of flotsam would experience in open water.  This is a far cry from the comparative stability of the thick and well interlocked central pack of old, I suspect.
Title: Re: The 2017 melting season
Post by: Jim Hunt on April 14, 2017, 09:31:20 AM
There's no sign of any activity on the North Pole Environmental Observatory web site, but nonetheless there is now an ice mass balance buoy in situ near the North Pole:

http://GreatWhiteCon.info/resources/ice-mass-balance-buoys/winter-201617-imb-buoys/#2017B (http://GreatWhiteCon.info/resources/ice-mass-balance-buoys/winter-201617-imb-buoys/#2017B)

To celebrate I've updated the IMB buoy temperature profiles slightly. The dotted lines at the left show maximum and minimum air temperature over the preceeding 24 hour period. The thermistor 1 reading is now in column 2.

As also reported by the the 2 Degrees North Pole Expedition (http://greatwhitecon.info/2017/04/2-degrees-north-pole-expedition/), it's warming up in the area.

Current Buoy Data (04/12/2017):

Pos: 89.19 N, 30.07 E
Air Temp: -15.56 C
Air Pres: 1020.69 mb
Snow depth : ? cm
Ice thickness : 172 cm
Title: Re: The 2017 melting season
Post by: JimboOmega on April 14, 2017, 05:42:28 PM
There's no sign of any activity on the North Pole Environmental Observatory web site, but nonetheless there is now an ice mass balance buoy in situ near the North Pole:

[url]http://GreatWhiteCon.info/resources/ice-mass-balance-buoys/winter-201617-imb-buoys/#2017B[/url] ([url]http://GreatWhiteCon.info/resources/ice-mass-balance-buoys/winter-201617-imb-buoys/#2017B[/url])

To celebrate I've updated the IMB buoy temperature profiles slightly. The dotted lines at the left show maximum and minimum air temperature over the preceeding 24 hour period. The thermistor 1 reading is now in column 2.

As also reported by the the 2 Degrees North Pole Expedition ([url]http://greatwhitecon.info/2017/04/2-degrees-north-pole-expedition/[/url]), it's warming up in the area.

Current Buoy Data (04/12/2017):

Pos: 89.19 N, 30.07 E
Air Temp: -15.56 C
Air Pres: 1020.69 mb
Snow depth : ? cm
Ice thickness : 172 cm


Can you explain the attached graph? Is that air temperature, per hour, on the 12th of April? As it reaches and seems to be steady at -2 that's a bit different than the quoted -15.6.

I'd be very surprised to see that temperature, especially that flat. Usually when I see a temperature graph go flat like that I assume it's because of an ongoing phase change.
Title: Re: The 2017 melting season
Post by: crandles on April 14, 2017, 05:51:45 PM
Can you explain the attached graph? Is that air temperature, per hour, on the 12th of April? As it reaches and seems to be steady at -2 that's a bit different than the quoted -15.6.

I'd be very surprised to see that temperature, especially that flat. Usually when I see a temperature graph go flat like that I assume it's because of an ongoing phase change.

There are sensors at 10cm intervals. High numbers are low down and yes -1.8C is a strong indicator of water or ice at phase change so those are beneath ice. Temperatures vary with ice and snow depth and air temps are shown by lowest numbered sensor.
HTH
Title: Re: The 2017 melting season
Post by: Jim Hunt on April 14, 2017, 06:08:55 PM
Can you explain the attached graph? Is that air temperature, per hour, on the 12th of April?


Wot Crandles said. A more detailed explanation can be found at:

http://GreatWhiteCon.info/resources/ice-mass-balance-buoys/ (http://GreatWhiteCon.info/resources/ice-mass-balance-buoys/)

It's not yet updated with the addition of air temperatures though..
Title: Re: The 2017 melting season
Post by: Andreas T on April 14, 2017, 10:28:43 PM
I tried to get an estimate of area  exported through Fram strait by tracking floes in worldview's AMSR2 layer https://go.nasa.gov/2ovmD1c (https://go.nasa.gov/2ovmD1c)
this is rather laborious, I made screenshots in approx 4 day steps, tracking backwards by frequent toggling layers in GIMP as recommended by A-team some while back
The red dots show position ice floes near the 80deg latitude  on the April 14th and where they were on February 12th. The outlined area is what has gone or is about to disapear via the Greenland sea.
Title: Re: The 2017 melting season
Post by: oren on April 14, 2017, 10:39:47 PM
Great animation Andreas. Any idea of the total distance moved? Is this something like 1000 km?
Title: Re: The 2017 melting season
Post by: Andreas T on April 14, 2017, 11:49:10 PM
Great animation Andreas. Any idea of the total distance moved? Is this something like 1000 km?
sorry, that 100km marker is only partly shown. On average the northern edge of the area is just south of 85degN. That makes it a little over 500km long. Width is about 300km
Title: Re: The 2017 melting season
Post by: oren on April 15, 2017, 12:12:56 AM
Thanks. Back of the envelope calculation: if the exported area (consisting mainly of older ice) was replaced by new ice somewhere in the CAB that is thinner by 2 meters, this is something like 300 km3 lost just by this mechanism in this vicinity, in addition to other export areas and of course the ice "lost" by lack of FDDs.
Title: Re: The 2017 melting season
Post by: slow wing on April 15, 2017, 12:58:06 AM
Great animation Andreas. Any idea of the total distance moved? Is this something like 1000 km?
sorry, that 100km marker is only partly shown. On average the northern edge of the area is just south of 85degN. That makes it a little over 500km long. Width is about 300km
Yes, very nice plot Andreas. Thanks for posting it.

Concerning the length of the designated region and its Northern edge, the North Pole is where the two lines of constant longitude intersect.  I used 2 rulers to find the point of intersection (i.e. the position of the North Pole, not shown in the images) and to extimate that the Northern edge of the designated area intersects the 0 degrees longitude line at ~86degN.

The length of the line segment inside the area and down to the 80degN curve is therefore 6 degrees of latitude, which is around 670 km.

So that means the ice starting at the Northern end of the line segment travelled about 670 km
out through the Fram Strait in the 2 months beginning on 12 February. That's an average flow speed of around 20 km per day.


Approximating your area by a rectangle with the Southern side at 80degN then the width of the rectangle is about 60% of its length.

So the ice area enclosed is ~ 0.6 x (670 km)^2 ~ 270,000 km^2

That area can be considered lost by export in ~61 days, or ~4400 km^2/day.

If assuming the ice thickness averages 2.3m = 0.0023 km then 4400 x 0.0023 = 10 km^3/day
is lost by Fram export; a total of ~600 km^3 over the 2 months.


If we approximate the maximum sea ice volume this year at ~20,000 km^3 (from PIOMAS) then the fraction lost is:
~600/20,000 ~ 3%.



So Andreas' animation shows about 3% of this year's maximum Arctic sea ice volume has been lost by export through the Fram Strait over the past 2 months.
Title: Re: The 2017 melting season
Post by: Tigertown on April 15, 2017, 05:36:09 AM
NSIDC saw a big drop for the 13th in SIE.

2017,    04,  12,     13.911
                                         x 106 km2
2017,    04,  13,     13.784
Title: Re: The 2017 melting season
Post by: romett1 on April 15, 2017, 08:16:39 AM
Bering Strait and Chukchi Sea Apr 12 - Apr 14. There were temperatures above 1°C and stronger winds, effectively open water already some 200 km from Diomede Islands. Images: Worldview.
Title: Re: The 2017 melting season
Post by: gerontocrat on April 15, 2017, 10:42:52 AM
Robertscribbler.com has an article on a "Brutish" anticyclone currently over the Beaufort sea causing havoc in the Bering strait , Laptev and Chukchi seas over the next few days, with consequent uptick in sea extent reduction / melting.
Title: Re: The 2017 melting season
Post by: romett1 on April 15, 2017, 11:02:27 AM
Robertscribbler.com has an article on a "Brutish" anticyclone currently over the Beaufort sea causing havoc in the Bering strait , Laptev and Chukchi seas over the next few days, with consequent uptick in sea extent reduction / melting.

Forecast is not good for ESS either, latest temp anomaly forecast until Apr 22 (GFS, Climate Reanalyzer).
Title: Re: The 2017 melting season
Post by: F.Tnioli on April 15, 2017, 12:51:02 PM
Right now, i am sitting in my appartment 1 km from Moscow, Russia. It is anomalously cold outside for the season: +2°C. We had many days way below average for the season, past month here. There is no snow for weeks, already. It's a sunny day, and again, we had several sunny days recently. Trees are still standing in their winter mode, no leaves.

How this relates to the Arctic melting season, you'd ask? Quite much.

I can't help but to think that all the cold we have here comes from the Arctic. Naturally, with the Sun shining like that, there is no other place for the cold to come from. So that means, huge mass of air came all the way from the Arctic down here, 55th parralel. And then obviously, up there in Arctic, some _other_ air took the place of the mass which came to Moscow; where would that "came to the Arctic" air come from? Inevitably, it'd come from somewhere which is not Arctic. Means, it was quite very warm air coming to Arctic, in huge amount. Not good for the ice.

And then there is even more. Now that that enourmous mass of air which cools down central Russia for weeks arrived here, - it's warming up. Fast. No snow and sunny days means low albedo and high insolation. No leaves on trees only further increases speed of that process. Lots and lots of heat is being stored into this air i got right out my window. And inevitably, some of that air will end up in Arctic once again, part of athmospheric circulation, - carrying some of heat it absorbs today right up there, to the ice in Arctic.

It doesn't feel good.

P.S. As visible from the forecast in the post just above, Scandinavia and much of North America landmasses are currently doing about the same thing, and will keep at it at even bigger negative anomaly than central Russia for the next few days: "stealing" cold from the Arctic, and warming all the air up extra fast whereever there is no snow cover already.
Title: Re: The 2017 melting season
Post by: Neven on April 15, 2017, 12:59:21 PM
Things on the move and opening up again in the Beaufort and Chukchi Seas:
Title: Re: The 2017 melting season
Post by: JayW on April 15, 2017, 01:46:31 PM
Alaska overview April 9-14.  I plan on making some higher resolution closeups when time allows.

http://feeder.gina.alaska.edu (http://feeder.gina.alaska.edu)

Title: Re: The 2017 melting season
Post by: iceman on April 15, 2017, 02:27:56 PM
   ....
this is rather laborious, I made screenshots in approx 4 day steps, tracking backwards by frequent toggling layers in GIMP as recommended by A-team some while back
   ....
Nice work, glad to see some of A-team's data visualization expertise percolating through the forum.
Title: Re: The 2017 melting season
Post by: oren on April 15, 2017, 02:32:17 PM
Looking at Hycom's Nowcast for the next few days, it seems openings are expected in Hudson and Kara.
Title: Re: The 2017 melting season
Post by: jai mitchell on April 15, 2017, 02:44:05 PM
   ....
this is rather laborious, I made screenshots in approx 4 day steps, tracking backwards by frequent toggling layers in GIMP as recommended by A-team some while back
   ....
Nice work, glad to see some of A-team's data visualization expertise percolating through the forum.

I remember he was talking about a GIMP extension that helped make these animations. 
Title: Re: The 2017 melting season
Post by: Bill Fothergill on April 15, 2017, 04:00:56 PM
@Bill Fothergill
... I assume you allow that I posted those on my facebook profile, else let me know

Magnamentis, apologies for not giving positive confirmation earlier. No real excuse, other than senility.  :P

Please feel free to use as you see fit.
Title: Re: The 2017 melting season
Post by: Bill Fothergill on April 15, 2017, 04:03:30 PM
What should be painfully clear is that there is a double whammy going on. Not only is the average maximum value decreasing, but the average loss leading up to the minimum is increasing. As a consequence, the ice remaining at the September minimum is feeling the pinch - from both sides.

Bill - Today I sent a link to Jim's PIOMAS chart that you "plagiarized" to a concerned but non-ice-obsessed neighbor, as I thought it was an excellent graphic.  I titled the email "A classic pincer move," a term from military strategy where you attack an enemy from two flanks simultaneously.

The phrase "classic pincer move" was exactly what went through my mind when I first saw Jim's PIOMAS chart.
Title: Re: The 2017 melting season
Post by: Tigertown on April 15, 2017, 10:42:28 PM
Another view of the Beaufort.
(http://)
Title: Re: The 2017 melting season
Post by: Jim Hunt on April 16, 2017, 12:44:12 PM
The AMSR2 regional area graphs confirm the effects of the recent anticyclonic winds:

http://GreatWhiteCon.info/2017/04/facts-about-the-arctic-in-april-2017/#comment-221417 (http://GreatWhiteCon.info/2017/04/facts-about-the-arctic-in-april-2017/#comment-221417)
Title: Re: The 2017 melting season
Post by: Shared Humanity on April 16, 2017, 03:05:38 PM
Not surprising the Chukchi is opening up early given the ridiculously thin ice. I expect the ESS, Laptev and Kara to do the same. The negative anomalies are horrendous in all of these seas. Even the anomalously thick ice piled up near the Wrangel, New Siberian and Severnaya Zemlya islands should be no cause for comfort as this is lousy, thin, first year ice that has ridged near these islands as a result of an endless succession of lows that raced through the CAB all winter.
Title: Re: The 2017 melting season
Post by: Bob Wallace on April 16, 2017, 04:37:16 PM
I tried to get an estimate of area  exported through Fram strait by....

Would it be useful to start a thread dedicated to ice movement through the Fram (and possibly other 'drains')?

Some years back some of us started suspecting that the last phase of the annual Arctic meltout would involve large transports of broken up, mobile ice out of the Arctic basin.  Much like how ice in rivers can suddenly break up and flush out. 

It seems like the Arctic flush is growing.  Transport out may be contributing a larger percentage of ice loss than in place melting.  I'd like a way to track changes in transport.

Title: Re: The 2017 melting season
Post by: Andreas T on April 16, 2017, 04:46:59 PM
good idea, easier to find stuff in dedicated threads. Somebody was looking into ice movement a while back but I can't remember who and wouldn't know where to start looking.
Title: Re: The 2017 melting season
Post by: bbr2314 on April 17, 2017, 03:36:02 AM
The ice is heating up quickly now, should probably be another two weeks or so until we see large parts begin to break 0C on a daily basis.

(http://ocean.dmi.dk/anim/plots/icetemp.arc.121.png)
Title: Re: The 2017 melting season
Post by: Tigertown on April 17, 2017, 05:36:03 AM
Worldview is down. Uni-Bremen is down. So, I went with what I could get.
Beaufort 15th(left) vs. 16th
I highly recommend using the zoom.
(http://)
Title: Re: The 2017 melting season
Post by: jdallen on April 17, 2017, 07:33:31 AM
Worldview is down. Uni-Bremen is down. So, I went with what I could get.
Beaufort 15th(left) vs. 16th
I highly recommend using the zoom.
(http://)
Dramatic and massive changes.  It looks to be catching up with 2016 pretty rapidly.
Title: Re: The 2017 melting season
Post by: romett1 on April 17, 2017, 09:25:23 AM

P.S. As visible from the forecast in the post just above, Scandinavia and much of North America landmasses are currently doing about the same thing, and will keep at it at even bigger negative anomaly than central Russia for the next few days: "stealing" cold from the Arctic, and warming all the air up extra fast whereever there is no snow cover already.

Same situation here in Tallinn, Estonia (900 km north-west from Moscow). By the way, this situation extends well into next week, latest temp anomalies Apr 18 - Apr 24 (GFS, Climate Reanalyzer).
Title: Re: The 2017 melting season
Post by: Neven on April 17, 2017, 11:22:39 AM
Uni Bremen SIC animation for April 12-16 (two more days after which things will probably slow down):
Title: Re: The 2017 melting season
Post by: JayW on April 17, 2017, 01:07:45 PM
Chukchi Sea April 13-16, about 78 hours

Suomi VIIRS imagery
http://feeder.gina.alaska.edu (http://feeder.gina.alaska.edu)
Title: Re: The 2017 melting season
Post by: Ninebelowzero on April 17, 2017, 01:42:39 PM
Very difficult to vector that sort of mobility into any prediction for September.
Title: Re: The 2017 melting season
Post by: Shared Humanity on April 17, 2017, 03:12:56 PM
What is frightening about these animations of the Beaufort and Chukchi is how fractured much of the ice is. Large portions look like rubble.
Title: Re: The 2017 melting season
Post by: jai mitchell on April 17, 2017, 05:14:21 PM
The Beaufort sea is still slightly below last year's record breakup for this day of the melt season.  It should be noted that the Beaufort had many sections of >3+ year ice still remaining (remember 'big block'?) 

There were greater wind events last year and (I suspect) the wind profile for the older ice was more condusive to breakup.  The overwhelming amount of thinner, younger ice in this year's beaufort sea is much more poised to meltout than last year even though the dispersion is (slightly) greater.
Title: Re: The 2017 melting season
Post by: jdallen on April 17, 2017, 05:16:03 PM
Very difficult to vector that sort of mobility into any prediction for September.
What is frightening about these animations of the Beaufort and Chukchi is how fractured much of the ice is. Large portions look like rubble.
Both true statements.

Also true, 2017 open water in the Chukchi and Bering seas has caught up to and passed 2016 in almost a matter of hours.  Conditions appear extraordinarily volatile.
Title: Re: The 2017 melting season
Post by: romett1 on April 17, 2017, 06:17:36 PM
Worldview is working again, here is ESS Apr 15 - Apr 17. ESS should also have the highest anomalies over the next 7 days. So many interesting areas over Arctic right now.
Title: Re: The 2017 melting season
Post by: Bill Fothergill on April 17, 2017, 08:29:24 PM
I know that there are many excellent examples being given on this thread demonstrating in exquisite detail how the melt season is progressing.

At a far more "broad-brush" level, and in response to a suggestion from Tor Bejnar, here is an updated version of a stacked bar chart showing how many "lowest 3 values for the date" are currently logged against the various years.

Here is a quick overview as to how one interprets the chart, and changes from the previous version.

1) Only 2006, 2007, 2010, 2011, 2012, 2015, 2016 and 2017 have meaningful numbers in the "lowest 3" categories, so all other years have been lumped together as "misc".

2) With the (hopefully) obvious exceptions of 2016 and 2017, each of the years has a group of 5 columns.

3) The first column in each year group shows the status at the end of 2015 - for the particular year indicated.

4) The second column shows the status at the end of 2016. The difference between cols 1 and cols 2 for each year therefore equates to the change wrought during 2016.

5) The third column shows the status as at the day/date indicated on the bottom right of the chart. The difference between this and the second column therefore indicates the impact that 2017 has had thus far.

6) The fourth column (marked "locked") indicates the number of "lowest 3" positions that have already been confirmed at the date the chart was generated. (In this case, Day 106, or 16th April)

7) The fifth column (marked "vulnerable") indicates the additional numbers that could hypothetically still be clocked up by December 31st 2017 - as long as there are no changes to positions from the equivalent dates last year. However, every additional day that 2017 has in the "lowest 3" will adversely impact at least one of the previous years.


For example, the first group of 5 relates to 2006. It can be seen that 2017 has already seen slightly more overall losses from the "lowest 3" than experienced in all of 2016. Additionally, although approximately half of the current instances have been "locked" by Day 106, approximately the same number could still be lost during the remainder of the year - i.e. they are vulnerable.

On the other hand, although 2010 lost ground during 2016, it has seen absolutely no change yet during 2017.


I hope this might help with the big picture perspective.

Title: Re: The 2017 melting season
Post by: Tor Bejnar on April 17, 2017, 08:47:11 PM
Very interesting, indeed, Bill.  (And for others: Bill took what I suggested [and ideas from others] and flew with it - my great idea ::) was under-developed when suggested  OR   if you don't like the changes, don't blame me ;D)
Title: Re: The 2017 melting season
Post by: CognitiveBias on April 17, 2017, 10:22:59 PM
Great chart.  One more idea... fwiw:  If you went 3D and made the z axis the ytd measure.  So the 3D chart grows in depth each day of the year.
Title: Re: The 2017 melting season
Post by: Thomas Barlow on April 18, 2017, 01:16:18 AM

P.S. As visible from the forecast in the post just above, Scandinavia and much of North America landmasses are currently doing about the same thing, and will keep at it at even bigger negative anomaly than central Russia for the next few days: "stealing" cold from the Arctic, and warming all the air up extra fast whereever there is no snow cover already.

Same situation here in Tallinn, Estonia (900 km north-west from Moscow). By the way, this situation extends well into next week, latest temp anomalies Apr 18 - Apr 24 (GFS, Climate Reanalyzer).


Not good news.
Arctic seems completely overheated most of the time.
If the average temperature is still well below freezing, does it matter about winter anomaly in the short term? Obviously not a good indication for summer or long-term, but freezing is freezing, so does it make a big difference? Yet?
Title: Re: The 2017 melting season
Post by: Michael Hauber on April 18, 2017, 01:44:14 AM
An interesting bit also is that the heat flow from the Atlantic peaked in 2007/2008 and has decreased slightly since.

Where does the time period end?

The data goes to 2016.  On further reading I've noticed that while temperature of the Atlantic water deeper down peaked (obviously temporarily) in 2007/2008 temps higher up in the Arctic waters have increased further since then, as mixing of this deeper water has increased in recent years.
Title: Re: The 2017 melting season
Post by: Archimid on April 18, 2017, 02:13:35 AM
If the average temperature is still well below freezing, does it matter about winter anomaly in the short term? Obviously not a good indication for summer or long-term, but freezing is freezing, so does it make a big difference? Yet?

Someone correct me if I'm wrong, but I think it does. The ice can get much colder than the freezing point. I imagine -30C ice would resist the melting season longer than -10C ice. Also I imagine that warmer ice have different physical characteristics as colder ice.
Title: Re: The 2017 melting season
Post by: Chuck Yokota on April 18, 2017, 02:47:13 AM
What Archimid said. Also, someone earlier gave the rule of thumb that seawater won't freeze above -10C due to mechanical effects. And ice will get thicker faster the lower the temperature goes.
Title: Re: The 2017 melting season
Post by: Okono on April 18, 2017, 03:38:13 AM
The actual energy required to melt colder ice is nominal, but feedbacks are literally all about second order effects, and those are really gnarly here.  I would expect our myriad satellite watchers to have more intuition about ice "rottenness" than anyone else.

Processes like brine rejection almost certainly take longer than anywhere has left at this point, though.  If we talk about ice quality in terms of the number of winters it takes to get properly seasoned, a month after vernal equinox is not likely to satisfy no matter what the weather does from here.

http://www.tms.org/pubs/journals/JOM/9902/Schulson-9902.html (http://www.tms.org/pubs/journals/JOM/9902/Schulson-9902.html)
Title: Re: The 2017 melting season
Post by: oren on April 18, 2017, 06:52:14 AM
What Archimid said. Also, someone earlier gave the rule of thumb that seawater won't freeze above -10C due to mechanical effects. And ice will get thicker faster the lower the temperature goes.
The main effect is ice not thickening enough, in the central arctic ice continues to thicken until May if I am not mistaken, and at -15oc it will thicken less and more slowly than at -30oc.
Title: Re: The 2017 melting season
Post by: jdallen on April 18, 2017, 07:14:04 AM
A stark illustration of how difficult our situation is.

Two daylight captures of the northern Bering, Chukchi, eastern ESS and Western Beaufort.

First is 04/17/2016

Second is 04/17/2017.

[Edit: Added for comparison, 05/17/2016]
[ADDITIONAL edit - I got the name stamps wrong on two of the images. 
From top to bottom:
2016-04-17
2017-04-17
2016-05-17
]
Title: Re: The 2017 melting season
Post by: DuraSpec on April 18, 2017, 12:51:41 PM
A stark illustration of how difficult our situation is.

Incredible! 3 pictures worth an untold number of words over the years.

Thank you for showing everyone.
Title: Re: The 2017 melting season
Post by: iceman on April 18, 2017, 01:43:10 PM
Chukchi Sea April 13-16, about 78 hours
   A striking view of a rare occurrence.

Very difficult to vector that sort of mobility into any prediction for September.
   Same for me.  I suppose the open areas will refreeze as the season is still quite early in Chukchi, but it seems likely the structural and thermal damage will be more lasting.
Title: Re: The 2017 melting season
Post by: seaicesailor on April 18, 2017, 02:21:10 PM
Chukchi Sea April 13-16, about 78 hours
   A striking view of a rare occurrence.

Very difficult to vector that sort of mobility into any prediction for September.
   Same for me.  I suppose the open areas will refreeze as the season is still quite early in Chukchi, but it seems likely the structural and thermal damage will be more lasting.

Also, I suspect there has been flow of Pacific water from south along the asian side (of the Pacific) into the Bering sea since Feb/March, which has been stagnating in the Bering sea, since the clearing of Bering sea ice up to the Bering strait has proceeded as a tongue entering from that side. Hycom indeed seemed to suggest such flow. Now this water could pour into the Arctic, representing the first significant pulse of water into the Arctic pretty early in the season.
See JAXA ice melt animation starting Mar 1
Title: Re: The 2017 melting season
Post by: Neven on April 18, 2017, 02:36:15 PM
A stark illustration of how difficult our situation is.

Two daylight captures of the northern Bering, Chukchi, eastern ESS and Western Beaufort.


Over on the Home brew AMSR2 thread Wipneus posted the following animation:

(http://forum.arctic-sea-ice.net/index.php?action=dlattach;topic=382.0;attach=44134;image)

Wip writes: Chukchi-ESS 2017 compared with 2016. Although some characteristics appear similar, the 2017 images show more breaking and "torching".
Title: Re: The 2017 melting season
Post by: Jim Williams on April 18, 2017, 04:16:38 PM
The MASIE Time Series Plots do seem to be indicating the Pacific side is opening up.
Title: Re: The 2017 melting season
Post by: Andreas T on April 18, 2017, 04:34:20 PM
last year (Feb / Mar 2016) there was a lot of movement of ice westward compacting and thickening against the siberian coast east of Wrangel island. The lack of this movement  makes the thickness there so much different (i.e. thinner this year) as seen in PIOMAS and in cryosat. This should show itself in the melt season which last year had a marked stall in June (red line is 2016)
https://14adebb0-a-62cb3a1a-s-sites.googlegroups.com/site/arctischepinguin/home/amsr2/grf/amsr2-extent-regional.png (https://14adebb0-a-62cb3a1a-s-sites.googlegroups.com/site/arctischepinguin/home/amsr2/grf/amsr2-extent-regional.png)
I tracked some of that compaction last year:
..... I have looked at deformation of ice in the western Chukchi sea where PIOMAS and cryosat are showing surprisingly thick ice.
The images are AMSR-2 brightness temperature on worldview [url]http://go.nasa.gov/1XXcE1b[/url] ([url]http://go.nasa.gov/1XXcE1b[/url])
Although I don't think I can relate the colours shown to thickness or other clearly identifiable parameters of the ice, they do show up persistent features which help tracking movement over long periods and through clouds. Unfortunately there are no AMSR-2 images in worldview before 12 Jan 2016.
I have marked some features which show a reduction in area between these features and therefore an increase in thickness, because at that time of the year volume does not decrease.
I expect that to happen through formation of ridges so that the average thickness includes first year ice with thickness below 2m together with overriding and tilted floe edges which form  the much thicker ridges.
dates are shown in file names: 4 Feb, 20 Feb, 5 Mar, 21 Mar

Title: Re: The 2017 melting season
Post by: seaicesailor on April 18, 2017, 05:52:51 PM
last year (Feb / Mar 2016) there was a lot of movement of ice westward compacting and thickening against the siberian coast east of Wrangel island. The lack of this movement  makes the thickness there so much different (i.e. thinner this year) as seen in PIOMAS and in cryosat. This should show itself in the melt season which last year had a marked stall in June (red line is 2016)
[url]https://14adebb0-a-62cb3a1a-s-sites.googlegroups.com/site/arctischepinguin/home/amsr2/grf/amsr2-extent-regional.png[/url] ([url]https://14adebb0-a-62cb3a1a-s-sites.googlegroups.com/site/arctischepinguin/home/amsr2/grf/amsr2-extent-regional.png[/url])
I tracked some of that compaction last year:
..... I have looked at deformation of ice in the western Chukchi sea where PIOMAS and cryosat are showing surprisingly thick ice.
The images are AMSR-2 brightness temperature on worldview [url]http://go.nasa.gov/1XXcE1b[/url] ([url]http://go.nasa.gov/1XXcE1b[/url])
Although I don't think I can relate the colours shown to thickness or other clearly identifiable parameters of the ice, they do show up persistent features which help tracking movement over long periods and through clouds. Unfortunately there are no AMSR-2 images in worldview before 12 Jan 2016.
I have marked some features which show a reduction in area between these features and therefore an increase in thickness, because at that time of the year volume does not decrease.
I expect that to happen through formation of ridges so that the average thickness includes first year ice with thickness below 2m together with overriding and tilted floe edges which form  the much thicker ridges.
dates are shown in file names: 4 Feb, 20 Feb, 5 Mar, 21 Mar


Definitely last year there was an stagnation of ice around the Chukchi/ESS sector of the CAB and the ESS that is not present this year. Perhaps the fact that during april there has been such a massive drift toward Atlantic/Fram while last year the flow was a bit different.
The ECMWF hints of yet three of four days of vigorous transpolar drift. The CFS weekly prediction nicely represented by TropicalTidbits kind of agrees with the nice "textbook" pattern of the coming days, less vigorous in the pacific side but massive still thanks to a low over Scandinavia coupling with the overall Arctic high pressure
Title: Re: The 2017 melting season
Post by: oren on April 18, 2017, 08:27:49 PM
Definitely last year there was an stagnation of ice around the Chukchi/ESS sector of the CAB and the ESS that is not present this year. Perhaps the fact that during april there has been such a massive drift toward Atlantic/Fram while last year the flow was a bit different.
Yes, the non-stop export towards the Atlantic gutted the arctic ocean leaving behind what seems like the same area and extent, but in reality thinner and weaker .
Title: Re: The 2017 melting season
Post by: romett1 on April 18, 2017, 08:50:04 PM
Some major cracks north of Ellesmere Island and Nares Strait have appeared overnight. Currently there are stronger winds (15 m/s) and warmer temps approaching as well. Image: http://ocean.dmi.dk/arctic/kennedy.uk.php (http://ocean.dmi.dk/arctic/kennedy.uk.php)
Title: Re: The 2017 melting season
Post by: meddoc on April 18, 2017, 09:11:36 PM
Some major cracks north of Ellesmere Island and Nares Strait have appeared overnight. Currently there are stronger winds (15 m/s) and warmer temps approaching as well. Image: [url]http://ocean.dmi.dk/arctic/kennedy.uk.php[/url] ([url]http://ocean.dmi.dk/arctic/kennedy.uk.php[/url])


This is very, very bad timing.
No wonder why the US is currently playing Nuclear Chicken with NK (& of course Russia and China).
Title: Re: The 2017 melting season
Post by: JimboOmega on April 18, 2017, 09:17:04 PM
If the average temperature is still well below freezing, does it matter about winter anomaly in the short term? Obviously not a good indication for summer or long-term, but freezing is freezing, so does it make a big difference? Yet?

Someone correct me if I'm wrong, but I think it does. The ice can get much colder than the freezing point. I imagine -30C ice would resist the melting season longer than -10C ice. Also I imagine that warmer ice have different physical characteristics as colder ice.

This is true but bear in mind that the energy associated with melting is far greater than the energy associated with heating.  Ice has a specific heat of 2.05kJ/kg*degree, while to melt it requires 333 kJ/kg

So to melt a kilogram of -30C ice would take ~393 kJ, while for -10C ice the figure is ~353kJ. Not a big difference really.

The reality with these air temps at this time of year is that newly exposed seawater (polynya, etc) can't refreeze. That's the biggest difference. Things can open up early and start soaking up that warm sunshine.  Since the temps are pretty close to freezing the atmosphere won't play too big a role for now.  (Later they can induce melt ponds and cause preconditioning, which is a whole separate thing)
Title: Re: The 2017 melting season
Post by: rboyd on April 18, 2017, 11:04:30 PM
Graph of relationship of temperature to the rate of increase in ice depth (for lake ice, but assume it holds relatively well for sea ice). The article also has a quite clear description of FDD's - I could follow it, so it must be pretty clear!

"Freezing degree days (FDD) are the average number of degrees below freezing over 24 hours. For example if the average temperature over a day is 17 degrees [fahrenheit] that day had fifteen FDDs"

http://lakeice.squarespace.com/ice-growth/ (http://lakeice.squarespace.com/ice-growth/)
Title: Re: The 2017 melting season
Post by: mati on April 19, 2017, 12:38:50 AM
The ice on the great lakes is going.. on my lake it is candling and should be gone in a week...

oh, about candling...
http://www.dnr.state.mn.us/climate/summaries_and_publications/ice_out_description.html (http://www.dnr.state.mn.us/climate/summaries_and_publications/ice_out_description.html)
Title: Re: The 2017 melting season
Post by: oren on April 19, 2017, 01:10:52 AM
Some major cracks north of Ellesmere Island and Nares Strait have appeared overnight. Currently there are stronger winds (15 m/s) and warmer temps approaching as well.
I think the Beaufort Gyre is back, looking at the various recent animations. And Hycom Nowcast https://www7320.nrlssc.navy.mil/hycomARC/navo/arcticictn_nowcast_anim30d.gif (https://www7320.nrlssc.navy.mil/hycomARC/navo/arcticictn_nowcast_anim30d.gif) shows the thick ice north of Ellesmere suddenly pulling westward in the last few days, after being swept towards the east for a long time. I bet this is what caused the sudden cracks, as the Ellesmere part pulled west while the Greenland part continued east.
I wonder if this could cause an early collapse of the Lincoln Sea "arch" blocking export to Nares Strait.
Title: Re: The 2017 melting season
Post by: Tigertown on April 19, 2017, 02:29:38 AM
I think the Beaufort Gyre is back

I was just thinking exactly that.
Title: Re: The 2017 melting season
Post by: Bruce Steele on April 19, 2017, 04:52:25 AM
Tigertown, I never saw any evidence the Beaufort Gyre had stopped. From the post I made on Mar. 31 ITP 98 has moved from 55.99 to it's current location at 55.56 The buoy track line never showed anything but clockwise drift and neither did the other two ITP buoys reporting locations in the Beaufort.


19
Arctic sea ice / Re: The 2017 melting season
« on: March 31, 2017, 07:39:58 AM »
Tigertown, There are still four ITP WHOI buoys reporting locations. Three in the Beaufort gyre 97, 98, 99 and  93 trapped into fast ice on the north coast of Svalbard.  The thing I find intriguing  is that none of the reporting buoys in the Beaufort gyre show the Northwest thick ice drift modeled in your last post. I have to believe buoys sending real time data over models in this case.
 I like to watch the temp /salinity contours but sadly we only have one of the above listed buoys still sending T/S profiles this year.

http://www.whoi.edu/page.do?pid=155136 (http://www.whoi.edu/page.do?pid=155136)

This buoy is sitting just North of McClure Strait and should show northward drift if the model was representing current conditions

http://www.whoi.edu/page.do?pid=155156 (http://www.whoi.edu/page.do?pid=155156)
ReplyQuoteNotify
Title: Re: The 2017 melting season
Post by: seaicesailor on April 19, 2017, 07:44:37 AM
Tigertown, I never saw any evidence the Beaufort Gyre had stopped. From the post I made on Mar. 31 ITP 98 has moved from 55.99 to it's current location at 55.56 The buoy track line never showed anything but clockwise drift and neither did the other two ITP buoys reporting locations in the Beaufort.


19
Arctic sea ice / Re: The 2017 melting season
« on: March 31, 2017, 07:39:58 AM »
Tigertown, There are still four ITP WHOI buoys reporting locations. Three in the Beaufort gyre 97, 98, 99 and  93 trapped into fast ice on the north coast of Svalbard.  The thing I find intriguing  is that none of the reporting buoys in the Beaufort gyre show the Northwest thick ice drift modeled in your last post. I have to believe buoys sending real time data over models in this case.
 I like to watch the temp /salinity contours but sadly we only have one of the above listed buoys still sending T/S profiles this year.

[url]http://www.whoi.edu/page.do?pid=155136[/url] ([url]http://www.whoi.edu/page.do?pid=155136[/url])

This buoy is sitting just North of McClure Strait and should show northward drift if the model was representing current conditions

[url]http://www.whoi.edu/page.do?pid=155156[/url] ([url]http://www.whoi.edu/page.do?pid=155156[/url])
ReplyQuoteNotify

Bruce, candid question: shouldn't we distinguish between ice drift, and the ocean current in the case of the Gyre?. The first has not shown a net clockwise pattern from December to March  (or at least really visible; maybe averaged over many days it is possible), the second, I cannot say but I assume it is there, still in with net clockwise sense, perhaps in a weakened phase... should take many years to stop or reverse the Gyre (ocean current)
Title: Re: The 2017 melting season
Post by: Tigertown on April 19, 2017, 07:55:19 AM
the second, I cannot say but I assume it is there, still in with net clockwise sense, perhaps in a weakened phase... should take many years to stop or reverse the Gyre (ocean current)

That was kind of my thoughts. I didn't really mean that it had gone completely so much, as just hadn't really exerted itself that much recently. Even at that, it was just a casual observation in agreement with oren. I didn't intend to make more of it than that.
Title: Re: The 2017 melting season
Post by: subgeometer on April 19, 2017, 08:55:27 AM
A view of the area south of a line between FJI(top left) and Svalbard(bottom left} from april2-18 shows the smashed up pack that has been pushed out into the Barents blowing back and forward and melting - with huge area of melt - 100km deep at times on the margin

I've included a larger still from April 8.

The area is going to cop a fair bit of wind from about 48hrs out  for a day or two. The wind will also be pulling away from the Siberian coast during its heatwave

(One interesting feature of worldview is that images downloaded thru its 'camera' interface have the date encoded in a TIME parameter in the url as the year and day in a n integer as YYYYDDD - eg April 12 as 2017102 allowing easy retrieval of a region (etc) over a period either in a browser or with a script - Is there a thread where image retrieval and animation are discussed?)
Title: Re: The 2017 melting season
Post by: romett1 on April 19, 2017, 09:36:41 AM
Warm temperatures forecasted until at least Apr 26 over ESS, Laptev, North Pole and Chukchi Sea (GFS, Climate Reanalyzer).
Title: Re: The 2017 melting season
Post by: Neven on April 19, 2017, 11:50:09 AM
NH snow cover shooting up now (mostly due to snowfall in Canada):
Title: Re: The 2017 melting season
Post by: Gray-Wolf on April 19, 2017, 12:56:55 PM
every time we see a cold plunge we see the Arctic lose its cold. if this is to continue in toward May even the last chance of growth in the central basin will have been tempered.

I'm sure we can now expect snowballs in the senate as both Canada and Western Europe endure a late cold snap but by the end of that we will be entering the first phase of melt season proper and see our first run of major losses.

With both Beaufort and ESS looking really poor how much open water will we have by June?
Title: Re: The 2017 melting season
Post by: gerontocrat on April 19, 2017, 04:13:11 PM
every time we see a cold plunge we see the Arctic lose its cold. if this is to continue in toward May even the last chance of growth in the central basin will have been tempered.

I'm sure we can now expect snowballs in the senate as both Canada and Western Europe endure a late cold snap but by the end of that we will be entering the first phase of melt season proper and see our first run of major losses.

With both Beaufort and ESS looking really poor how much open water will we have by June?
And while Canada and W. Europe have a cold snap warmth invades the high Arctic for the nth time, where n is a surprisingly large number.
And weather-forecast.com predicts a windy time in a southerly direction down the Fram and Denmark straits for the next few days.
Ps: I think that maybe snowballs in the senate are not so effective anymore.
Title: Re: The 2017 melting season
Post by: Tigertown on April 19, 2017, 04:59:29 PM
subgeometer
Is there a thread where image retrieval and animation are discussed?

Yes, to the animation part, anyway.

http://forum.arctic-sea-ice.net/index.php/topic,1259.msg89520.html#msg89520
Title: Re: The 2017 melting season
Post by: bbr2314 on April 19, 2017, 05:23:52 PM
NH snow cover shooting up now (mostly due to snowfall in Canada):

Volume-wise, the uptick has also been singificant, wayyyy beyond +1SD at this point, that is a huge anomaly!

(https://ccin.ca/home/sites/default/files/snow/snow_tracker/nh_swe.png)

Seems to be led by NE Siberia, Quebec, and the Western Himalayas:

(https://ccin.ca/home/sites/default/files/snow/snow_tracker/plot_anom_sdep.png)
Title: Re: The 2017 melting season
Post by: bairgon on April 19, 2017, 06:51:43 PM
Some major cracks north of Ellesmere Island and Nares Strait have appeared overnight.

There are also smaller cracks above the Nares arch - see https://worldview.earthdata.nasa.gov/?p=arctic&l=VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor,Reference_Labels(hidden),Reference_Features(hidden),Coastlines&t=2017-04-18&z=3&v=-335502.5695521517,-818827.6264782081,-89742.56955215175,-692747.6264782081 (https://worldview.earthdata.nasa.gov/?p=arctic&l=VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor,Reference_Labels(hidden),Reference_Features(hidden),Coastlines&t=2017-04-18&z=3&v=-335502.5695521517,-818827.6264782081,-89742.56955215175,-692747.6264782081) and gif below.

This also shows that the month-old ice in the polynya has given way.

There is also a crack on the coast of Greenland (explore on Worldview using link above).
Title: Re: The 2017 melting season
Post by: Tigertown on April 19, 2017, 07:08:28 PM
Uni-Bremen is back up. Mr. Artie C. Ice is not looking too great.
(http://)
Title: Re: The 2017 melting season
Post by: Neven on April 19, 2017, 07:33:38 PM
Seems to be led by NE Siberia, Quebec, and the Western Himalayas:

Keep an eye on those Western Himalayas, especially during summer.  ;)
Title: Re: The 2017 melting season
Post by: Random_Weather on April 19, 2017, 08:01:19 PM
Neven,

Yes, therefor i use the finnish service for Snowmass, because they cutting out mountain sides: http://www.globsnow.info/swe/GCW/ (http://www.globsnow.info/swe/GCW/)

(http://www.globsnow.info/swe/GCW/GCW_Snow_Watch_plot_20170418_SWE_NRT_v1.3.png)
Title: Re: The 2017 melting season
Post by: nukefix on April 19, 2017, 08:32:28 PM
Neven,

Yes, therefor i use the finnish service for Snowmass, because they cutting out mountain sides: [url]http://www.globsnow.info/swe/GCW/[/url] ([url]http://www.globsnow.info/swe/GCW/[/url])


AFAIK the Globsnow algorithm is the best-in-business currently.
Title: Re: The 2017 melting season
Post by: Neven on April 19, 2017, 09:40:21 PM
Here's an Uni Hamburg AMSR2 SIC animation of the Beaufort, with some more detail because of highest resolution:
Title: Re: The 2017 melting season
Post by: bbr2314 on April 19, 2017, 10:33:24 PM
Seems to be led by NE Siberia, Quebec, and the Western Himalayas:

Keep an eye on those Western Himalayas, especially during summer.  ;)
I will! I think there is definitely a possibility you are correct re: error, but I have also found an abundance of writing that signals the Western Himalayas (and Karakorum specifically) reversed the trends of glacial recession sometime around 2000, with mass-loss halted entirely and even reversed in the period 2000-2010. If that is the case, then we are building on snowcover year over year in some of these spots, which could also be an explanation for the abundance of purples. Can't wait to read more research into this phenomenon one way or the other.
Title: Re: The 2017 melting season
Post by: mati on April 19, 2017, 10:51:33 PM
could it be that the increased water vapour content of the atmosphere will result in more snow being deposited on high altitude glaciers?
Title: Re: The 2017 melting season
Post by: Shared Humanity on April 19, 2017, 11:22:18 PM
could it be that the increased water vapour content of the atmosphere will result in more snow being deposited on high altitude glaciers?

That would be a good thing.
Title: Re: The 2017 melting season
Post by: Jim Williams on April 19, 2017, 11:25:34 PM
could it be that the increased water vapour content of the atmosphere will result in more snow being deposited on high altitude glaciers?

That is the most common WACC (Warm Arctic Cold Continents) theory.  Basically, the theory is that until "General" warming overcomes local conditions the continents will get colder and wetter as the Arctic fails to keep the cold locked up in the far North.

Title: Re: The 2017 melting season
Post by: oren on April 19, 2017, 11:38:46 PM
Reminder that a recent thread exists somewhere on the forum dealing with snow cover anomalies and new glaciation.
Title: Re: The 2017 melting season
Post by: seaicesailor on April 19, 2017, 11:55:41 PM
I am liking these weekly CFS forecast visualisations of Tropicaltidbits. Somehow the CFS forecast retains a lot that the ECMWF and GFS forecast for the coming seven days and it is nice to observe some consistency and agreement in a single averaged-values map.
One thing is that a sustained strong winds favoring Fram export.
The second is that, while no above zero temps are forecasted over the Arctic, they indeed will be reached in many locations of Siberia (at brief moments), in agreement with the CFS predicted southerlies and warmer than average temps.
Beaufort sea Anticiclonic and cold for a while. Should be quite sunny though, stable situation all pacific side.

Getting closer to the real melting season so to speak.
Title: Re: The 2017 melting season
Post by: seaicesailor on April 20, 2017, 12:14:06 AM
Granted this is valid for 5 days most, but I wonder if this is the recurrent configuration Ding was referring to: highs persistent over Greenland Canada and Arctic with lows pulling warmth from the continents (in summer). Just a comment, not sure it is even close :-)
Title: Re: The 2017 melting season
Post by: slow wing on April 20, 2017, 01:37:56 AM
Attached is a month-by-month gif of the ice coverage maps from the Arctic and Antarctic Research Institute, St. Petersburg, Russia,
http://www.aari.ru/odata/_d0015.php?lang=1 (http://www.aari.ru/odata/_d0015.php?lang=1).

The maps are interesting because they track the old ice that has survived at least one melt season - shown in reddish-brown.

One example map was chosen for each month from 2016-10 to 2017-04, with a date around 18th of each month.

Apologies for my poor gif-making skills.

 The gif seems to show a continuing loss of the old ice on the Russian and Atlantic sides that extends in time all the way through to the January 2017 frame. This happened despite new ice completely surrounding the old ice region.

  It is seen that the old ice has been pushed away from the Russian side and also nibbled away at on the Atlantic side - the infamous 'Atlantic kill zone'.

   The pattern by now seems to be a continuation of that movement away from the Russian side. That is now driving a bifurcation, with some of the compressed ice turning left and heading towards the Atlantic side kill zone and the rest turning right towards the Beaufort Sea.

   The latter seems to be the 'Beaufort gyre' setting up due to the recent high pressure systems in the Beaufort. If that continues then this year will again have a wall of old ice between the Beaufort Sea and Central Arctic Basin (CAB), albeit thinner ice than last year.
Title: Re: The 2017 melting season
Post by: Bob Wallace on April 20, 2017, 02:09:01 AM
could it be that the increased water vapour content of the atmosphere will result in more snow being deposited on high altitude glaciers?

Yes, but with rising temperatures the snowline will retreat further up the mountains.  And as the line rises the area of real estate decreases rapidly.
Title: Re: The 2017 melting season
Post by: subgeometer on April 20, 2017, 04:33:16 AM
subgeometer
Is there a thread where image retrieval and animation are discussed?

Yes, to the animation part, anyway.

http://forum.arctic-sea-ice.net/index.php/topic,1259.msg89520.html#msg89520
[/quoTigertown
Title: Re: The 2017 melting season
Post by: jdallen on April 20, 2017, 09:16:03 AM
Look for major drops in extent in the Bering over the next few days.
Title: Re: The 2017 melting season
Post by: jdallen on April 20, 2017, 09:28:36 AM
Browsing around tonight in worldview, there are hundreds of thousands of KM2 that look like they are right on the edge of vanishing; it's not just the Bering.  If  you look in the Kara, along the margins of the Barents, the Bering, the Okhotsks, Baffin, the Greenland, you will see huge expanses like that shown below. 

This image is from south central Baffin, and the image is about 250,000KM2 total.
Title: Re: The 2017 melting season
Post by: DrTskoul on April 20, 2017, 11:18:12 AM
Granted this is valid for 5 days most, but I wonder if this is the recurrent configuration Ding was referring to: highs persistent over Greenland Canada and Arctic with lows pulling warmth from the continents (in summer). Just a comment, not sure it is even close :-)
Wayne Davidson's new cold North pole....
Title: Re: The 2017 melting season
Post by: Rick Aster on April 20, 2017, 05:16:02 PM
Look for major drops in extent in the Bering over the next few days.

Temperatures are rising above freezing all afternoon in Nome, Alaska, maybe not today but for the next seven days in the Weather Underground forecast. https://www.wunderground.com/cgi-bin/findweather/getForecast?query=Nome%2C+AK (https://www.wunderground.com/cgi-bin/findweather/getForecast?query=Nome%2C+AK) Nome should be one of the cooler spots on the Bering Sea coast and the temperature forecast is more than enough to keep the melting trend going. Temperatures at night are not quite cold enough for refreezing and a month after spring equinox, the nights are not very long anyway.

The temperature at Utqiagvik (Barrow), by contrast, might not reach the melting point until well into May. That's the difference between 64 and 71 degrees N.
Title: Re: The 2017 melting season
Post by: gerontocrat on April 20, 2017, 06:28:45 PM
So much data saying Melt (DMI, Arctic anomaly, Fram export, destruction of  sea ice sheets integrity from multiple observations  etc. etc.). And yet jaxa sea ice decline remains at a glacial pace, and sea ice volume not declining yet.
And still at least 2 weeks before getting April PIOMAS  update. Am I the only one in confusion ?
Title: Re: The 2017 melting season
Post by: Buddy on April 20, 2017, 06:45:07 PM

The temperature at Utqiagvik (Barrow), by contrast, might not reach the melting point until well into May. That's the difference between 64 and 71 degrees N.

The last several weeks (and maybe more) the Russian side of the Arctic has been where all the warm anomaly's have been hanging out.  There....and in the CAB.  The Canadian/Alaska side of the Arctic has been much cooler.

The graphic below for the upcoming 27th is representative of what HAS been happening over the recent weeks...




Title: Re: The 2017 melting season
Post by: Pragma on April 20, 2017, 06:48:53 PM
And still at least 2 weeks before getting April PIOMAS  update. Am I the only one in confusion ?

No, you definitely are not. I accept that various methods will differ slightly, but the ones that you mention not only differ a great deal in magnitude but also in trend.

In my simplistic view, any method needs to regularly checked against other lines of evidence and then recalibrate the process or adjust the model. I am sympathetic to the difficulties of making the measurements, but even so, it appears that one or more of the products is not much more than a guess and someone is going to be very embarrassed soon.

Perhaps if error bars were included, then we could see if there is any overlap in the uncertainties. This would reduce the temptation to take any single value as gospel.

As Mark Knopfler said "Two men say they're Jesus, one of them must be wrong" :-)
Title: Re: The 2017 melting season
Post by: Tigertown on April 20, 2017, 07:38:36 PM
Nothing to be confused about, really. It's just dispersion. And remember, if you get to a fork in the road, take the fork.
Title: Re: The 2017 melting season
Post by: pauldry600 on April 20, 2017, 07:49:31 PM
Looking at W Europe next week the Arctic unlocking of the cold seems in place.

Just look at Northern Spain.

Frost in the UK not really strange for this time of year  but as was said previously the melt is dispersing the cold more whereas when its locked in only the Northern parts of the continents have cold.

Its like the world is punctured and all the cold air is going everywhere but since everywhere is larger than somewhere the severity is nowhere.
Title: Re: The 2017 melting season
Post by: oren on April 20, 2017, 07:52:15 PM
gerontocrat, if you check the regional AMSR2 extent chart at https://14adebb0-a-62cb3a1a-s-sites.googlegroups.com/site/arctischepinguin/home/amsr2/grf/amsr2-extent-regional.png (https://14adebb0-a-62cb3a1a-s-sites.googlegroups.com/site/arctischepinguin/home/amsr2/grf/amsr2-extent-regional.png) you will see that Barents + Greenland Sea (victims of Fram export) and Baffin (southbound drift) are running high in extent - this is ice on its way to hell - while the Pacific side (Bering, Okhotsk, Chukchi) is running low. The ice is weak, thin and broken but is still covering the same extent. All this setup will have a lot to say when the actual melting season begins (now it's just the very southern edges). Patience will be rewarded unfortunately.
Title: Re: The 2017 melting season
Post by: jdallen on April 20, 2017, 08:42:44 PM
So much data saying Melt (DMI, Arctic anomaly, Fram export, destruction of  sea ice sheets integrity from multiple observations  etc. etc.). And yet jaxa sea ice decline remains at a glacial pace, and sea ice volume not declining yet.
And still at least 2 weeks before getting April PIOMAS  update. Am I the only one in confusion ?
I think the answer is dispersion, GC.  Less ice, spread more thinly.
Title: Re: The 2017 melting season
Post by: Tigertown on April 20, 2017, 09:36:54 PM
Lots of thin ice.
(http://)
Title: Re: The 2017 melting season
Post by: Jim Williams on April 20, 2017, 11:46:59 PM
So much data saying Melt (DMI, Arctic anomaly, Fram export, destruction of  sea ice sheets integrity from multiple observations  etc. etc.). And yet jaxa sea ice decline remains at a glacial pace, and sea ice volume not declining yet.
And still at least 2 weeks before getting April PIOMAS  update. Am I the only one in confusion ?
I think the answer is dispersion, GC.  Less ice, spread more thinly.

AKA -- Winter Storms.
Title: Re: The 2017 melting season
Post by: subgeometer on April 21, 2017, 09:57:43 AM
The Bering and Chukchi from April 15-21 with april 19 2016 by way of comparison. Doesn't look good
Title: Re: The 2017 melting season
Post by: Bill Fothergill on April 21, 2017, 10:28:25 AM
Great chart.  One more idea... fwiw:  If you went 3D and made the z axis the ytd measure.  So the 3D chart grows in depth each day of the year.

Thanks. I've played about a bit with the 3-D idea, but the presentation looks messy.

It seems a bit of a no-brainer to use the Y-axis for the dependent variable (number of days in "lowest 3") and use the X- and Z-axes for each of the independent variables (i.e. the year, and the day/date within year). Swapping the X- & Z-axes obviously radically alters the appearance, but neither looks good.

I've also had a bit of problem trying to implement a stacked display (i.e. showing cumulative lowest, 2nd lowest & 3rd lowest stacked on top of each other) using the 3-D format.

However, I have a cunning plan on how to circumvent this limitation, and will try it out tonight or tomorrow.


Thanks again for the f/b.
Title: Re: The 2017 melting season
Post by: oren on April 21, 2017, 01:19:28 PM
The Bering and Chukchi from April 15-21 with april 19 2016 by way of comparison. Doesn't look good
Terrible. All heading towards the (Fram) exit.
Title: Re: The 2017 melting season
Post by: iceman on April 21, 2017, 03:01:36 PM
   ....
   The pattern by now seems to be a continuation of that movement away from the Russian side. That is now driving a bifurcation, with some of the compressed ice turning left and heading towards the Atlantic side kill zone and the rest turning right towards the Beaufort Sea.
   ....

The movement of MYI toward the Atlantic side draws the eye, but "the dog that didn't bark" is the lack of rotation into Beaufort.  (At least my impression - without doing proper y/y comparisons - is that it's much less than normal.)
    Given moderate winds and mixed temperatures for the next week or longer in the general Beaufort Gyre region, it seems likely that area/extent will hold up fairly well in the early melt season. But I have a bad premonition about the effect of melt ponding there.
Title: Re: The 2017 melting season
Post by: Thomas Barlow on April 21, 2017, 09:33:26 PM
So much data saying Melt (DMI, Arctic anomaly, Fram export, destruction of  sea ice sheets integrity from multiple observations  etc. etc.). And yet jaxa sea ice decline remains at a glacial pace, and sea ice volume not declining yet.
And still at least 2 weeks before getting April PIOMAS  update. Am I the only one in confusion ?

I think the answer is dispersion, GC.  Less ice, spread more thinly.


AKA -- Winter Storms.

Does it make a difference if you just look at the main Arctic Basin?
Are there any charts that try to gauge thickness or volume for just the main Arctic Basin?

Here, below, I have taken out the thickest ice (4-5m) that clings, or is pushed against land mass. Some of that thick ice would probably still be there, even if the Arctic ever opens up in summer, as some say it will some day. And I also deleted most of the ice that forms in all the channels between islands.

A lot of that ice in channels, and the ice packed up against the land mass, could still be there even if the central Arctic Basin eventually starts to break up. So this may be a more realistic comparison, reguarding the major icepack, and reguarding what is essentially going on, that counts the most in assessing the state of the central icepack.

On the left 21 April 2012, and on the right 20 April 2017.

http://polarportal.dk/en/havisen-i-arktis/nbsp/sea-ice-extent/ (http://polarportal.dk/en/havisen-i-arktis/nbsp/sea-ice-extent/)
Title: Re: The 2017 melting season
Post by: Tigertown on April 22, 2017, 04:03:37 AM
NSIDC SIE has been on a downward track of late.

2017,    04,  12,     13.911
2017,    04,  13,     13.785
2017,    04,  14,     13.717
2017,    04,  15,     13.740
2017,    04,  16,     13.704
2017,    04,  17,     13.738
2017,    04,  18,     13.667
2017,    04,  19,     13.624
2017,    04,  20,     13.592
Title: Re: The 2017 melting season
Post by: meddoc on April 22, 2017, 08:16:54 AM
This opening is very unusual up that high. I suspect warm SSTs and atlantification.
Title: Re: The 2017 melting season
Post by: cesium62 on April 22, 2017, 08:19:54 AM
On the left 21 April 2012, and on the right 20 April 2017.

2012 was not particularly thin ice (compared to other recent years) in mid-april.  Yes, whatever weather condition cleared the ice out in 2012 re-occurs in 2017, the ice is going to have a big problem.  2011 and 2016 might be better comparisons for relatively thin ice in April and a low extent in September?


Title: Re: The 2017 melting season
Post by: oren on April 22, 2017, 08:39:39 AM
This opening is very unusual up that high. I suspect warm SSTs and atlantification.
meddoc your suspicion is wrong, please read the "Nares Strait" thread in the Greenland section. There is an almost-constant surface flow from the Lincoln Sea southwest down the strait. When the thick ice gets stuck at the entrance it may form an "arch", as happened this year (more often an arch is created in Kane Basin at the other end of the strait). The surface flow then keeps clearing the area below the arch.
Also search the web for the "North Water Polynya".
Title: Re: The 2017 melting season
Post by: meddoc on April 22, 2017, 09:15:05 AM
This opening is very unusual up that high. I suspect warm SSTs and atlantification.
meddoc your suspicion is wrong, please read the "Nares Strait" thread in the Greenland section. There is an almost-constant surface flow from the Lincoln Sea southwest down the strait. When the thick ice gets stuck at the entrance it may form an "arch", as happened this year (more often an arch is created in Kane Basin at the other end of the strait). The surface flow then keeps clearing the area below the arch.
Also search the web for the "North Water Polynya".

I'm sorry I don't care about peer- reviewed Articles anymore.
Common sense and basic phsyics knowledge seem to be enough to understand, open water above 75 North this time of Year is not an indicator of a coming Ice Age.
Title: Re: The 2017 melting season
Post by: romett1 on April 22, 2017, 10:36:08 AM
Latest temp anomalies forecast for Apr 23 - Apr 29 (GFS, Climate Reanalyzer). Pacific side and Russian coast still warm, next week there is also "heat wave" over Baffin Bay, Greenland and Fram Strait. This is interesting, because temps are above freezing over Fram Strait, I just remember how much damage they (high temps) did once in winter.
Title: Re: The 2017 melting season
Post by: seaicesailor on April 22, 2017, 02:39:57 PM
A close-up of the evolution of SST anomalies in Bering sea during past 30 days or so (from the DMI SST anomalies maps). Insolation and ocean currents make a difference there already.
Title: Re: The 2017 melting season
Post by: Thomas Barlow on April 22, 2017, 03:25:28 PM
On the left 21 April 2012, and on the right 20 April 2017.

2012 was not particularly thin ice (compared to other recent years) in mid-april.  Yes, whatever weather condition cleared the ice out in 2012 re-occurs in 2017, the ice is going to have a big problem.  2011 and 2016 might be better comparisons for relatively thin ice in April and a low extent in September?
Here is the comparison for 2016 .
Are there any charts that try to gauge thickness or volume for just the main Arctic Basin?
All the charts take into account all the channels and east Greenland, and may not say much about state of main Arctic Basin icepack.
( I took out the thick ice that is pushed up against land masses, as I think some of that would be there anyway, even in a future meltdown, and doesn't tell us too much about the state of the overall icepack in the Arctic Basin. And I took out ice in channels and Fram export, as those are not really part of the main state of the Arctic basin icepack)
I'd say 2017 looks in worse shape than 2016?
Title: Re: The 2017 melting season
Post by: iceman on April 22, 2017, 03:41:27 PM
So much data saying Melt (DMI, Arctic anomaly, Fram export, destruction of  sea ice sheets integrity from multiple observations  etc. etc.). And yet jaxa sea ice decline remains at a glacial pace, and sea ice volume not declining yet.
And still at least 2 weeks before getting April PIOMAS  update. Am I the only one in confusion ?
I think the answer is dispersion, GC.  Less ice, spread more thinly.
... Barents + Greenland Sea (victims of Fram export) and Baffin (southbound drift) are running high in extent - this is ice on its way to hell - while the Pacific side (Bering, Okhotsk, Chukchi) is running low. The ice is weak, thin and broken but is still covering the same extent....

Looks as if dispersion in Baffin/Newfoundland is now being slowed or interrupted; likewise for Greenland Sea next week.  Meanwhile there are two other reasons to expect continued slow area/extent declines for a little while longer:
   - cold anomalies over northern Canada, warm anomalies in the central basin (haven't seen any discussion of AO index lately - maybe in a different forum thread?
   - lack of heat and moisture advection on the Atlantic side, as the lows have been mostly meandering farther south rather than intensifying and moving northward past Iceland
     Net, no cliff formation in sight.  We'll have to track melt ponding and concentration to predict whether it arrives in May or June.
Title: Re: The 2017 melting season
Post by: Neven on April 22, 2017, 08:48:02 PM
This opening is very unusual up that high. I suspect warm SSTs and atlantification.

It's less unusual than one would think. I believe in the past decade it has happened 2-3 times before. Google 'Nares' and 'Patrick Lockerby' (who occasionally posts here as logicman).

And peruse the Nares Strait thread. And I've written about Nares regularly on the ASIB (and would this year as well if it wasn't for the sabbatical).
Title: Re: The 2017 melting season
Post by: Neven on April 22, 2017, 08:53:52 PM

Here is the comparison for 2016 .
Are there any charts that try to gauge thickness or volume for just the main Arctic Basin?
All the charts take into account all the channels and east Greenland, and may not say much about state of main Arctic Basin icepack.
( I took out the thick ice that is pushed up against land masses, as I think some of that would be there anyway, even in a future meltdown, and doesn't tell us too much about the state of the overall icepack in the Arctic Basin. And I took out ice in channels and Fram export, as those are not really part of the main state of the Arctic basin icepack)
I'd say 2017 looks in worse shape than 2016?

Nice comparisons, TB. It's always good to compare years within one dataset, but keep in mind that of all modelled volume distribution maps (besides ACNFS and PIOMAS) this one from DMI is deemed least trustworthy. And I forgot new player ADS/JAXA, which doesn't seem to be very trustworthy either.

But again, it never hurts to compare years, even within not so reliable datasets.
Title: Re: The 2017 melting season
Post by: Thomas Barlow on April 22, 2017, 11:28:51 PM
This compares thickness, for certain thickness ranges only.
Between 2016 and 2017.
(I'm guessing most sources out there are just approximate, with a wide margin of error?)
Title: Re: The 2017 melting season
Post by: seaicesailor on April 23, 2017, 12:07:50 AM
Interesting that this polynya that appeared about 1 week ago in ESS is about the only one within the Arctic proper not showing signs of refreeze. Why there?
Being April 22 big chances it will stay open.
Title: Re: The 2017 melting season
Post by: cesium62 on April 23, 2017, 02:23:38 AM
This compares thickness, for certain thickness ranges only.
Between 2016 and 2017.
(I'm guessing most sources out there are just approximate, with a wide margin of error?)

Thanks.  Fun stuff.
Title: Re: The 2017 melting season
Post by: cesium62 on April 23, 2017, 02:37:15 AM
Interesting that this polynya that appeared about 1 week ago in ESS is about the only one within the Arctic proper not showing signs of refreeze. Why there?
Being April 22 big chances it will stay open.

Wipneus' ESS amsr2 extent graph suggests the ESS doesn't typically start melting and opening up until mid-May.  I would have guessed that suggested a reasonable chance of refreeze or a change in wind direction that would close the opening?
Title: Re: The 2017 melting season
Post by: Hyperion on April 23, 2017, 03:13:54 AM
Interesting that this polynya that appeared about 1 week ago in ESS is about the only one within the Arctic proper not showing signs of refreeze. Why there?
Being April 22 big chances it will stay open.

I'm afraid you are seeing the result of a week long surge of warm nth pacific water coming thru Bering and rushing along the ESAS at up to 100km per day.

https://worldview.earthdata.nasa.gov/?p=arctic&l=VIIRS_SNPP_CorrectedReflectance_TrueColor,MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),Reference_Labels(hidden),Reference_Features(hidden),Coastlines&t=2017-04-22&z=3&v=-2342667.648686028,1311881.675158471,-1294091.6486860283,1843337.675158471&ab=off&as=2017-04-15&ae=2017-04-22&av=4&al=true
Title: Re: The 2017 melting season
Post by: Hyperion on April 23, 2017, 03:17:53 AM
Not sure why that gif won't play ???
Title: Re: The 2017 melting season
Post by: Archimid on April 23, 2017, 03:26:21 AM
I thought it was caused by warm and humid wind intrusion that started the 13th of april. The warmth of that event is still lingering in the Arctic.

https://earth.nullschool.net/#2017/04/13/2100Z/wind/surface/level/overlay=temp/orthographic=-166.03,64.59,1548

If you follow that heat you'll notice how it gets in the arctic and then head north. I think that wind had the effect of pushing (melting and compression?) the ice and raising the temperatures in the Arctic. If you keep following it probably helped export a bit.
Title: Re: The 2017 melting season
Post by: Chuck Yokota on April 23, 2017, 03:36:48 AM
Interesting that this polynya that appeared about 1 week ago in ESS is about the only one within the Arctic proper not showing signs of refreeze. Why there?
Being April 22 big chances it will stay open.

That area is above -10C, so wave and wind activity will prevent freezing.
Title: Re: The 2017 melting season
Post by: Hyperion on April 23, 2017, 09:35:22 AM
Lets try a homemade one rather than a NASA nasty.
Its quite stunning how fast the current is surging along there. I know that often warmer salty water slides in on the bottom through the Bering straight, while it can even be flowing out on the surface. Certainly if its Pacific water making it all the way along there, the offshore wind would blow the fresher lens away and help it surface.

Still not playing. is there a size limit?
I guess yes.  ::)

Title: Re: The 2017 melting season
Post by: oren on April 23, 2017, 10:07:25 AM
Thanks for the animation. ~700 pixel width is the trick.
And, are you sure it's a current and not wind-driven? If it's a current it's really bad news.
Title: Re: The 2017 melting season
Post by: Hyperion on April 23, 2017, 10:28:34 AM
A close-up of the evolution of SST anomalies in Bering sea during past 30 days or so (from the DMI SST anomalies maps). Insolation and ocean currents make a difference there already.

Its less than 50m deep all along there. Whether or not its wind driven, its a current. And as SIS pointed out with his excellent animation a few days ago....
I think you are right about trouble. Big burst of warm SST was charging up the Russian coast for Bering.
Title: Re: The 2017 melting season
Post by: JayW on April 23, 2017, 11:42:28 AM
Beaufort April 12-23, the gyre began gyrating, but has slowed as the Beaufort looks like it's importing sea ice over the past few days.


Suomi VIIRS imagery

http://feeder.gina.alaska.edu (http://feeder.gina.alaska.edu)

Title: Re: The 2017 melting season
Post by: romett1 on April 23, 2017, 11:51:23 AM

Its quite stunning how fast the current is surging along there.

Thanks Hyperion. This must be current, because wind direction has been towards Pacific. I compared Apr 22 this year vs 2016. Not the best situation and we know that temps are mild over next 7 days there. Also looked long-term forecast (CFS), first week of May still large positive anomalies over Chukchi Sea and ESS coast. Images: Worldview.
Title: Re: The 2017 melting season
Post by: seaicesailor on April 23, 2017, 01:14:19 PM
Lets try a homemade one rather than a NASA nasty.
Its quite stunning how fast the current is surging along there. I know that often warmer salty water slides in on the bottom through the Bering straight, while it can even be flowing out on the surface. Certainly if its Pacific water making it all the way along there, the offshore wind would blow the fresher lens away and help it surface.

Still not playing. is there a size limit?
I guess yes.  ::)
Nice animation. Yes I agree on the surge of Pacific water. ACNFS has been showing a stream toward the bering Strait since March, so probably this has been running under the ice for longer than a week, but since Hycom ACNFS animations are not really clear on that, this is just a suspicion that the first pulse of Pacific water has come really early this year. Which is aggravated by a anomalously warmer atmospheric situation and a really crappy ice to start with! Thin and broken.

The CFS long-range prediction as wonderfully represented in Levi Cowan's site (tropicaltidbits.com) shows a Siberia anomalously warm for the month of May. Last month it predicted the emergence of Beaufort high pressure many days in advance when the Arctic was completely dominated by lows, it was surprising how well it predicted it. Keeping an eye on these forecasts, we'll see if they serve during summer.

I believe the CFS-v2 model has been recently changed (impacting for instance El Niño predictions), but others here may know more about that.
Title: Re: The 2017 melting season
Post by: Thomas Barlow on April 23, 2017, 01:33:13 PM
I just added " >1.5m " ice to the bottom of my post on previous page (18), re. ice thickness in the Arctic Basin 2016 vs 2017.
Even more interesting.
Unfortunately, it's not looking very robust.

Click here, scroll down ---> https://forum.arctic-sea-ice.net/index.php/topic,1834.msg110856.html#msg110856
Title: Re: The 2017 melting season
Post by: Andreas T on April 23, 2017, 03:15:52 PM

Its quite stunning how fast the current is surging along there.

Thanks Hyperion. This must be current, because wind direction has been towards Pacific. I compared Apr 22 this year vs 2016. Not the best situation and we know that temps are mild over next 7 days there. Also looked long-term forecast (CFS), first week of May still large positive anomalies over Chukchi Sea and ESS coast. Images: Worldview.
Archimid has shown wind blowing in the direction of ice movement, so no, repeated assertions "this must be current" are not enough to convince me that this is what's happening. We know ice is thinner there this year, which makes movement easier and air temperatures are not cold enough to freeze water opened by ice movement, that is the most plausible explanation unless someone has other information.
Title: Re: The 2017 melting season
Post by: subgeometer on April 23, 2017, 03:27:30 PM
Thanks for the animation. ~700 pixel width is the trick.
And, are you sure it's a current and not wind-driven? If it's a current it's really bad news.

Ther looks to be melt on Asian side going thru Bering strait last little while, so I was thinking the same thing. Someone else also posted a sst animation that suggested that as well

[edit]
But past Wrangel Island is a long way, there's no melting goodbye waves in that polynya

[/edit]
Title: Re: The 2017 melting season
Post by: Archimid on April 23, 2017, 04:49:11 PM
I made the following animation to illustrate the event that I am talking about.

To reproduce it start in the following link and and move forward in 3 hours step:

https://earth.nullschool.net/#2017/04/12/0900Z/wind/surface/level/overlay=temp/orthographic=-174.04,70.59,1082

The event began the 13th and kept going for a few days. Then there was another smaller event around the end of the 17th. The humidity of theses events still lingers in the Arctic.

I do not know the cause-effect relationship of this warm air intrusion with water currents. I wouldn't be surprised if both the water and the atmosphere are playing a part in this.
Title: Re: The 2017 melting season
Post by: romett1 on April 23, 2017, 05:05:02 PM

Archimid has shown wind blowing in the direction of ice movement, so no, repeated assertions "this must be current" are not enough to convince me that this is what's happening. We know ice is thinner there this year, which makes movement easier and air temperatures are not cold enough to freeze water opened by ice movement, that is the most plausible explanation unless someone has other information.

I was thinking about Apr 19, Apr 20 and Apr 22, there were winds towards Pacific. I tried to check speed of the current, latest from earth.nullschool was 600 m per hour towards Arctic Basin (Apr 12).
Title: Re: The 2017 melting season
Post by: seaicesailor on April 23, 2017, 08:24:59 PM

Its quite stunning how fast the current is surging along there.

Thanks Hyperion. This must be current, because wind direction has been towards Pacific. I compared Apr 22 this year vs 2016. Not the best situation and we know that temps are mild over next 7 days there. Also looked long-term forecast (CFS), first week of May still large positive anomalies over Chukchi Sea and ESS coast. Images: Worldview.
Archimid has shown wind blowing in the direction of ice movement, so no, repeated assertions "this must be current" are not enough to convince me that this is what's happening. We know ice is thinner there this year, which makes movement easier and air temperatures are not cold enough to freeze water opened by ice movement, that is the most plausible explanation unless someone has other information.
Alright... but in that animation there are some floes moving like impelled by strong currents near the fast ice, does seem a bit too fast to be just the wind.
And why so much difference with Laptev sea...
Anyway, it really calls the attention
Edit. Attached a cropped version of Hyperion's gif showing only the area of the channel between Wrangel island and the ESS fast ice. A lot of momentum there
There's a floe there that flies more than 100 km in a single day (or more, almost like length of Wrangel which is more like 150 km). The 1/30 rule of thumb says a wind of 120 km/h would be needed to generate such drift... am I missing something?
Title: Re: The 2017 melting season
Post by: Andreas T on April 24, 2017, 01:51:33 AM
I can see a floe which is at 175E 70.15N on the 20th and moves about 70km to the next image on the 21st. We don't know for sure when these images were taken because the tiling can be irregular so maybe not exactly 24h. Nullschool gives wind speed of 27km/h as a max for early on the 20th, falling to 16km/h later.
I don't claim to know much about velocity of ocean currents but expect them to be lower, the example in bering strait given earlier was in hundreds of meters an hour. The way velocity picks up from one day to the next and directions change in these ice movements make me more inclined to think of them driven by wind. Do ocean currents change that quickly?
We saw similar fast movement of floes in Beaufort last year near the edge of the pack, my hunch then was that local eddies are spun by currents which move in different directions in deeper and shallower water. Maybe ice driven by wind produces local current at the surface?
I don't know the 1/30th rule, can you explain?


Title: Re: The 2017 melting season
Post by: Tigertown on April 24, 2017, 05:55:54 AM
NSIDC SIE has been on a downward track of late.

2017,    04,  12,     13.911
2017,    04,  13,     13.785
2017,    04,  14,     13.717
2017,    04,  15,     13.740
2017,    04,  16,     13.704
2017,    04,  17,     13.738
2017,    04,  18,     13.667
2017,    04,  19,     13.624
2017,    04,  20,     13.592
Continuing Downward, though gradually
2017,    04,  21,     13.562
2017,    04,  22,     13.493

(http://)
Title: Re: The 2017 melting season
Post by: Rob Dekker on April 24, 2017, 07:26:47 AM
It is amazing to see the Bering strait into the Chukchi sea already essentially open while it is still April. I seem to recall that in the Nautilus could not find a way through the thick ice in 1958 in June :

On 19 June she entered the Chukchi Sea, but was turned back by deep drift ice in those shallow waters.
From Wikipedia although I'm sure there are more detailed accounts of that journey.

How times have changed...
Title: Re: The 2017 melting season
Post by: seaicesailor on April 24, 2017, 08:32:44 AM
I can see a floe which is at 175E 70.15N on the 20th and moves about 70km to the next image on the 21st. We don't know for sure when these images were taken because the tiling can be irregular so maybe not exactly 24h. Nullschool gives wind speed of 27km/h as a max for early on the 20th, falling to 16km/h later.
I don't claim to know much about velocity of ocean currents but expect them to be lower, the example in bering strait given earlier was in hundreds of meters an hour. The way velocity picks up from one day to the next and directions change in these ice movements make me more inclined to think of them driven by wind. Do ocean currents change that quickly?
We saw similar fast movement of floes in Beaufort last year near the edge of the pack, my hunch then was that local eddies are spun by currents which move in different directions in deeper and shallower water. Maybe ice driven by wind produces local current at the surface?
I don't know the 1/30th rule, can you explain?
Makes sense (that around that cape there may be some local effect, some eddie acting on the floe). You are right about the current, 600 m/h is not negligible anyway, but much slower indeed.
The 1/30th rule of thumb is something I came up with last year to estimate the proportion between sustained winds speeds and generated drift speed. It is not accurate by all means depending in many factors (in fact, for instance, in that paper by Zhang and others about the GAC the ratio implied for the drifting marginal  ice in CAB under the storm was more like 1/20th iirc). It's just an order of magnitude that works ok. In steady state the pull due to wind and drag due to water are of same order (not the same since there is Coriolis) and further assuming similar surface and bottom drag coefficients the ratio of speeds goes with the square root of density air/water. As I said, really crude but it gets close when the floes are already loose.
Title: Re: The 2017 melting season
Post by: Hyperion on April 24, 2017, 01:32:33 PM
I've been trying to unpick the Current Bering Strait and Chukchi behavior. I don't think its too hard to understand. Two weeks ago as the monster high pressure started to build, there was much outflow and flushing of Ice thru the strait. Now the last week as low pressure is returning the current is surging back in. Despite the only time the winds in the strait or sth pacific have even looked slightly conducive to pushing anything Nth, and just barely,was the seventeenth.
1hpa of pressure is approximately equivalent to 1 cm of sea level. The drop in basin wide mean atmospheric pressure seems a good 20hpa since the 1049 peak. Equivalent to 20cm of sea level. And additionally there has been a very concerted effort by the winds in the Arctic quadrant to push water out that side. Still continuing. Quite some significant storm surge developed I'm sure. Even pushed a big tail of hot salty from over Iceland down around the Southern cape of Greenland.
So it appears that it is the Arctic and Atlantic that are sucking not so much that the Pacific blows. ;)
I am not so sure that any of the Nullschool current feeds are accurate. The berg movement through bering seems much faster than the 0.14m/s nth they always output there. Don't think they update it much. There definately seems to be pockets heading off down the siberian coast at the same SSTAs as the water getting thru on the Russian side.
Whats more the geography is quite ideal for a suck effect from strong east to west movement as was set up by the big High. There is a small Harbour entrance not far from where I am currently Anchored with the Greentech R&D Vessel , the 25m 60ton stone KiteShip White Rose ( https://www.google.co.nz/maps/@-36.766848,175.4722841,39m/data= (https://www.google.co.nz/maps/@-36.766848,175.4722841,39m/data=)!3m1!1e3?hl=en  ) that behaves this way. When there's a full ebb tide running, that entrance rushes INTO the harbour at about 12kmph! Thought I'd lost my marbles and got the tides back to front when I first saw it! :o Very similar current venturi effect. 8)

I wasted my time doing a gif of the Bering closeup today. T.T beat me to it! ;D What a waste of Solar Electrickyharvestin! A bit short on supply this week.  ::) And Thar be no baby petroleums murdered for any purpose on this vessel, ARR to be sure! :) 
Title: Re: The 2017 melting season
Post by: JayW on April 24, 2017, 01:40:10 PM
I made a number of gifs to investigate the east Siberian sea shore.  I want sure what view folks would prefer.  The GINA puffin feeder site has time stamps for more accurate assessment.

Suomi VIIRS imagery from the University of Alaska at Fairbanks.

http://feeder.gina.alaska.edu/search?commit=Search&page=4&search%5Bend%5D=&search%5Bfeeds%5D%5B5%5D=1&search%5Bsensors%5D%5B3%5D=1&search%5Bstart%5D=&utf8= (http://feeder.gina.alaska.edu/search?commit=Search&page=4&search%5Bend%5D=&search%5Bfeeds%5D%5B5%5D=1&search%5Bsensors%5D%5B3%5D=1&search%5Bstart%5D=&utf8=)✓

First attachment is April 13-23 overview as close to 24 hours spaced between frames at roughly 22z each day.


Second attachment is a close up of the first.


Third attachment is April 20-23 with multiple frames per day to get s better sense of the sub daily movement.


Fourth attachment is mean surface wind vector from April 13-21


It appears to my untrained eye that the bulk of movement is wind driven, but I imagine currents must also be present, I am just not sure how to figure how much to attribute to each.  There's not a ton of "open space" were the ice can freely move, so it's a really small "sample size" to draw conclusions from.  Once the ice begins packing together, wind and current have much less effect I imagine.  Sorry if all the animations are an annoyance.


Edit: I removed one gif as it appeared redundant, and can't figure out why that one gif will not run.
Title: Re: The 2017 melting season
Post by: Thomas Barlow on April 24, 2017, 03:27:42 PM
It might be interesting if they didn't include the years from 2010 onwards in their "Mean Volume". Including those just makes the average descend down the chart each year, and gives a false impression, because the most recent years are lowest on record, and declining more as we speak. The average from 1979-2010 would be much higher up on the chart, and it would show we are in a precipitous decline in the last 5-7 years, at least compared to the average of modern records.

Does anyone have the data skills to create such a chart? ... with only 1979-2010 included for the average (black-dotted line).
It would be interesting to see the difference in the chart, caused by the last several low-volume years.
Title: Re: The 2017 melting season
Post by: Niall Dollard on April 24, 2017, 06:14:06 PM
A year on year look at the Beaufort. Far less cracks. Give it time though I suppose.

(http://i1018.photobucket.com/albums/af306/stratoq/nasa-worldview-2016-04-23-to-2017-04-23.gif) (http://s1018.photobucket.com/user/stratoq/media/nasa-worldview-2016-04-23-to-2017-04-23.gif.html)
Title: Re: The 2017 melting season
Post by: Buddy on April 24, 2017, 06:44:01 PM
A year on year look at the Beaufort. Far less cracks. Give it time though I suppose.

I think that...if someone (maybe you?) would do the same thing with the RUSSIAN SIDE (central coast) of the Arctic, that comparison would likely show the opposite.  Especially over the last month or so.....the Alaskan coast and the Canadian Archipelago have been cooler than normal....while the Russian coast has been hit with much warmer temps than normal...
Title: Re: The 2017 melting season
Post by: Archimid on April 24, 2017, 06:59:48 PM
 I'm hoping to get the hang of this GIF stuff. Here you are buddy. They are from the 22nd of April since there were less clouds then.
Title: Re: The 2017 melting season
Post by: Thomas Barlow on April 24, 2017, 11:19:45 PM
A year on year look at the Beaufort. Far less cracks. Give it time though I suppose.

According to this, it is much thicker in the peripheral Beaufort than last year.
(but thinner elsewhere in the Arctic this year, than 2016)
Title: Re: The 2017 melting season
Post by: Bob Wallace on April 24, 2017, 11:20:28 PM
It might be interesting if they didn't include the years from 2010 onwards in their "Mean Volume". Including those just makes the average descend down the chart each year, and gives a false impression, because the most recent years are lowest on record, and declining more as we speak. The average from 1979-2010 would be much higher up on the chart, and it would show we are in a precipitous decline in the last 5-7 years, at least compared to the average of modern records.

Does anyone have the data skills to create such a chart? ... with only 1979-2010 included for the average (black-dotted line).

I suspect a certain flightless bird with a drippy nose could crank that out.  He's already doing other charts with the PIOMAS data. 

https://sites.google.com/site/arctischepinguin/home/piomas/grf/piomas-trnd2.png

(https://sites.google.com/site/arctischepinguin/home/piomas/grf/piomas-trnd2.png)

Let me add, I think that's an excellent idea.  Moving the goalpost is hardly ever a good idea.
Title: Re: The 2017 melting season
Post by: Thomas Barlow on April 24, 2017, 11:34:13 PM
Interesting.
North Pole ice is 2.75m thick, whereas it was 4m+ thick this time last year.
No wonder Barneo did a retreat.
http://forum.arctic-sea-ice.net/index.php/topic,1905.msg111027.html#msg111027 (http://forum.arctic-sea-ice.net/index.php/topic,1905.msg111027.html#msg111027)
Title: Re: The 2017 melting season
Post by: Thomas Barlow on April 24, 2017, 11:46:41 PM
Interesting.
According to this - http://polarportal.dk/en/havisen-i-arktis/nbsp/sea-ice-extent (http://polarportal.dk/en/havisen-i-arktis/nbsp/sea-ice-extent) - a lot of 5m thick ice off Ellesmere island & Greenland, but open water in channel. Strange.
Title: Re: The 2017 melting season
Post by: Thomas Barlow on April 24, 2017, 11:48:36 PM
It might be interesting if they didn't include the years from 2010 onwards in their "Mean Volume". Including those just makes the average descend down the chart each year, and gives a false impression, because the most recent years are lowest on record, and declining more as we speak. The average from 1979-2010 would be much higher up on the chart, and it would show we are in a precipitous decline in the last 5-7 years, at least compared to the average of modern records.

Does anyone have the data skills to create such a chart? ... with only 1979-2010 included for the average (black-dotted line).

I suspect a certain flightless bird with a drippy nose could crank that out.  He's already doing other charts with the PIOMAS data. 

Let me add, I think that's an excellent idea.  Moving the goalpost is hardly ever a good idea.
Who?
(who is the flightless bird. Can he do it?)
Title: Re: The 2017 melting season
Post by: Hyperion on April 24, 2017, 11:51:35 PM
A year on year look at the Beaufort. Far less cracks. Give it time though I suppose.

([url]http://i1018.photobucket.com/albums/af306/stratoq/nasa-worldview-2016-04-23-to-2017-04-23.gif[/url]) ([url]http://s1018.photobucket.com/user/stratoq/media/nasa-worldview-2016-04-23-to-2017-04-23.gif.html[/url])


How Strange. I guess everyone's eyes are different, and its often easy to see what you want to see. But when I look at these comparisons I see significantly more cracks than 2016. And of course the results of a strong four day compaction event that's just occurred. I hope it doesn't mean I want to see everything crack up. ::)
Title: Re: The 2017 melting season
Post by: seaicesailor on April 25, 2017, 12:05:11 AM
A year on year look at the Beaufort. Far less cracks. Give it time though I suppose.

([url]http://i1018.photobucket.com/albums/af306/stratoq/nasa-worldview-2016-04-23-to-2017-04-23.gif[/url]) ([url]http://s1018.photobucket.com/user/stratoq/media/nasa-worldview-2016-04-23-to-2017-04-23.gif.html[/url])


How Strange. I guess everyone's eyes are different, and its often easy to see what you want to see. But when I look at these comparisons I see significantly more cracks than 2016. And of course the results of a strong four day compaction event that's just occurred. I hope it doesn't mean I want to see everything crack up. ::)

Yes but the area of open water was completely crazy. This year it looks more normal and its been really cold.
"Give it time", well indeed according to the forecasts a high over Beaufort is back on day 4 from today and somehow warmer temps too. First weeks of May we see what happens with the cracks. They look really solid now!
Title: Re: The 2017 melting season
Post by: dnem on April 25, 2017, 12:16:53 AM
It might be interesting if they didn't include the years from 2010 onwards in their "Mean Volume".

Does anyone have the data skills to create such a chart? ... with only 1979-2010 included for the average (black-dotted line).
It would be interesting to see the difference in the chart, caused by the last several low-volume years.

Here's a crack with a line for 1979-2010 added.
Title: Re: The 2017 melting season
Post by: Thomas Barlow on April 25, 2017, 12:20:51 AM
It might be interesting if they didn't include the years from 2010 onwards in their "Mean Volume".

Does anyone have the data skills to create such a chart? ... with only 1979-2010 included for the average (black-dotted line).
It would be interesting to see the difference in the chart, caused by the last several low-volume years.

Here's a crack with a line for 1979-2010 added.
Ok, not a huge difference, but thanks for doing that !
Interesting to see.
Title: Re: The 2017 melting season
Post by: Hyperion on April 25, 2017, 12:41:31 AM
A year on year look at the Beaufort. Far less cracks. Give it time though I suppose.

([url]http://i1018.photobucket.com/albums/af306/stratoq/nasa-worldview-2016-04-23-to-2017-04-23.gif[/url]) ([url]http://s1018.photobucket.com/user/stratoq/media/nasa-worldview-2016-04-23-to-2017-04-23.gif.html[/url])


How Strange. I guess everyone's eyes are different, and its often easy to see what you want to see. But when I look at these comparisons I see significantly more cracks than 2016. And of course the results of a strong four day compaction event that's just occurred. I hope it doesn't mean I want to see everything crack up. ::)

Yes but the area of open water was completely crazy. This year it looks more normal and its been really cold.
"Give it time", well indeed according to the forecasts a high over Beaufort is back on day 4 from today and somehow warmer temps too. First weeks of May we see what happens with the cracks. They look really solid now!

Methinks there's circumstantial illusions created by a chrono-illogical snapshot. The shadow effect NW of the big Bergs and off the coast exaggerates the appearance of open water in the 2016 shot. Obviously due to a strong offshore DISPERSAL and polynia creation event with warm incoming air for a number of days coming in off Canada. This cherry pick of an inverse snapshot appears to show a crunch where all the fragments and slush are shoved first along the fringe of the CAA, then rammed into the armpit of the Alaskan/Canada border, the CAA catching like a strainer, and the persistent freezing winds off the Pole and CAA for the period, No doubt with wind blown snow to dust on top of the slush assisting, creating a greasy slick of Nilas.
 If you have a lot of slush and rubble dispersed well in the gaps between the bergs, like this year. Then refreeze in the cracks is obviously easier. But if a slight increase in contrast and simultaneous downward tweak of brightness takes most of the stuff between the large chunks out of those images, as I confess I did above, I doubt there's much insolation difference between the grease and the open water of last year.
Title: Re: The 2017 melting season
Post by: gregcharles on April 25, 2017, 12:42:13 AM

I suspect a certain flightless bird with a drippy nose could crank that out.  He's already doing other charts with the PIOMAS data. 

Let me add, I think that's an excellent idea.  Moving the goalpost is hardly ever a good idea.
Who?
(who is the flightless bird. Can he do it?)

I think Bob is referring to Arctic Penguin (https://sites.google.com/site/arctischepinguin/home). :)
Title: Re: The 2017 melting season
Post by: oren on April 25, 2017, 12:57:58 AM
Interesting.
According to this - [url]http://polarportal.dk/en/havisen-i-arktis/nbsp/sea-ice-extent[/url] ([url]http://polarportal.dk/en/havisen-i-arktis/nbsp/sea-ice-extent[/url]) - a lot of 5m thick ice off Ellesmere island & Greenland, but open water in channel. Strange.

I am quoting a response I've made upthread to a similar inquiry:
This opening is very unusual up that high...

...please read the "Nares Strait" thread in the Greenland section. There is an almost-constant surface flow from the Lincoln Sea southwest down the strait. When the thick ice gets stuck at the entrance it may form an "arch", as happened this year (more often an arch is created in Kane Basin at the other end of the strait). The surface flow then keeps clearing the area below the arch.
Also search the web for the "North Water Polynya".
Title: Re: The 2017 melting season
Post by: Bob Wallace on April 25, 2017, 01:29:02 AM

I suspect a certain flightless bird with a drippy nose could crank that out.  He's already doing other charts with the PIOMAS data. 

Let me add, I think that's an excellent idea.  Moving the goalpost is hardly ever a good idea.
Who?
(who is the flightless bird. Can he do it?)

I think Bob is referring to Arctic Penguin (https://sites.google.com/site/arctischepinguin/home). :)

Yes, Wipneus.    But I seem to have messed up the translation.  In Dutch it's "tipped up nose"  or "turned up nose".  Not dripping. 
Title: Re: The 2017 melting season
Post by: pauldry600 on April 25, 2017, 01:42:59 AM
I thought sea ice would be way less by now.

I think my estimate of 3.7m minimum has a heap of catching up to do to happen. In the past 20 days apart from bering its been boring
Title: Re: The 2017 melting season
Post by: Niall Dollard on April 25, 2017, 01:54:22 AM
Methinks there's circumstantial illusions created by a chrono-illogical snapshot. The shadow effect NW of the big Bergs and off the coast exaggerates the appearance of open water in the 2016 shot. Obviously due to a strong offshore DISPERSAL and polynia creation event with warm incoming air for a number of days coming in off Canada. This cherry pick of an inverse snapshot


Shadow effect NW of the bergs?? I think not.

Cherry pick? Not intended.

Around this time last year the Beaufort was going through a torrid time. I expect many year on year comparisons of the Beaufort around this time +/- two weeks will look quite similar.

I too don't intend to crack up trying to quantify it. These are just snapshots.

Jim Hunt has archived some more images during that April/May period last year here :

http://greatwhitecon.info/resources/arctic-regional-graphs/beaufort-sea-ice-graphs/ (http://greatwhitecon.info/resources/arctic-regional-graphs/beaufort-sea-ice-graphs/)

From a vertical perspective, in my opinion it looks better there now. But that is compared against an early opening last year. Of course it is difficult to gauge what the true thickness is underneath. Although Thomas' thickness charts posted earlier do suggest it is thicker at the periphery at least.

It will be interesting to see how things develop over the Beaufort in the coming weeks. 

Title: Re: The 2017 melting season
Post by: Darvince on April 25, 2017, 03:41:13 AM
I dare say the only year the situation in the Beaufort is better than is last year. 2012 and 2013 are also available in Worldview, but early 2013 is rotated 90 degrees compared to the rest of the dataset. Both of them had even less cracks, and 2013 looked like this year did before high pressure moved in to Beaufort. However, 2012's cracks were very long, oriented longitudinally, and contained open water between them.

Click to animate!
Title: Re: The 2017 melting season
Post by: Rob Dekker on April 25, 2017, 04:10:38 AM
It might be interesting if they didn't include the years from 2010 onwards in their "Mean Volume".

Does anyone have the data skills to create such a chart? ... with only 1979-2010 included for the average (black-dotted line).
It would be interesting to see the difference in the chart, caused by the last several low-volume years.


Here's a crack with a line for 1979-2010 added.


And here one graph from Wipneus, with the baseline 1979-2001 included :

(http://neven1.typepad.com/.a/6a0133f03a1e37970b01bb098cffa0970d-pi)

Either way, and from the graphs posted earlier, it is clear that sea ice 'volume' is on a persistent and potentially catastrophic decline. 2017 is especially noteworthy, because of the current record low PIOMAS numbers.

To quote Neven from the ASIB :
the average of total melt for the past 10 years is 18269 km3, which means that at the end of this year's melting season the minimum could be only 2526 km3 (the lowest minimum on record reached in 2012 was 3673 km3). If we take the lowest amount of volume growth since the end of March (2007), and subtract the highest total melt (19693 km3 in 2010) from that potential maximum, the minimum could even go lower than 1000 km3!


We'll see what September 2017 brings us, but it seems clear that there is a good chance that we are about to find out if the Arctic summer melts ice 'volume' or if it melts 'extent'.
Title: Re: The 2017 melting season
Post by: Rob Dekker on April 25, 2017, 04:45:40 AM
JayW said
Sorry if all the animations are an annoyance.

Are you kidding ?
JayW, your animations are amazing and very informative.
Please keep on working your magic.
Title: Re: The 2017 melting season
Post by: oren on April 25, 2017, 06:02:53 AM
I dare say the only year the situation in the Beaufort is better than is last year. 2012 and 2013 are also available in Worldview, but early 2013 is rotated 90 degrees compared to the rest of the dataset. Both of them had even less cracks, and 2013 looked like this year did before high pressure moved in to Beaufort. However, 2012's cracks were very long, oriented longitudinally, and contained open water between them.
Darvince, thanks for the animation. One thing 2016 had and this year seems to lack is the thick old MYI - we can see Big Block nicely even in this early date in 2016. Early open water in 2016 brought about a lot of melt momentum later, but this year the "momentum" might be built in due to the lack of resistance once actual melt starts.
Title: Re: The 2017 melting season
Post by: romett1 on April 25, 2017, 09:31:50 AM
Bering Strait is like washing machine, Apr 22 - Apr 24, Worldview.
Title: Re: The 2017 melting season
Post by: JayW on April 25, 2017, 11:36:35 AM
4 animations, all from April 1-24.  Last year is certainly striking, but it's of my opinion that there's little to no melt going on in any of these years during this time frame.  We are really looking at movement.  2016 is dramatic in the Beaufort, but I feel that much of that ice was shoved into the Chukchi ESS region.  2017 we see ice being imported into the Beaufort once it loosened (my opinion) and the Beaufort hasn't exactly been a sanctuary for ice the last few years...

Suomi VIIRS imagery from the puffin feeder site at the University of Alaska at Fairbanks
http://feeder.gina.alaska.edu/search?utf8= (http://feeder.gina.alaska.edu/search?utf8=)✓&search%5Bsensors%5D%5B3%5D=1&search%5Bfeeds%5D%5B16%5D=1&search%5Bfeeds%5D%5B1%5D=1&search%5Bfeeds%5D%5B15%5D=1&search%5Bfeeds%5D%5B17%5D=1&search%5Bfeeds%5D%5B3%5D=1&search%5Bfeeds%5D%5B18%5D=1&search%5Bfeeds%5D%5B10%5D=1&search%5Bfeeds%5D%5B11%5D=1&search%5Bfeeds%5D%5B9%5D=1&search%5Bfeeds%5D%5B8%5D=1&search%5Bfeeds%5D%5B12%5D=1&search%5Bfeeds%5D%5B13%5D=1&search%5Bfeeds%5D%5B14%5D=1&search%5Bfeeds%5D%5B6%5D=1&search%5Bfeeds%5D%5B5%5D=1&search%5Bstart%5D=&search%5Bend%5D=&commit=Search

Really hope these all run, nope, I'll try again.

Puzzled, all the gifs are made the same way.  Oh well, I'll try to add 2014 a different way
(http://i.imgur.com/TBVqG6I.jpg])

Attachments

First 2014
Second 2015
Third 2016
Fourth 2017
Title: Re: The 2017 melting season
Post by: Neven on April 25, 2017, 12:28:21 PM
JayW, animations are hardly ever annoying. Thanks for posting.
Title: Re: The 2017 melting season
Post by: dosibl on April 25, 2017, 03:19:51 PM
PIOMAS firmly has us in a volume anomaly, but area/extent are still in the same ballpark as years past. I'm concerned the square-cube law might throw a curveball in how fast/how much volume melts out.
Title: Re: The 2017 melting season
Post by: romett1 on April 25, 2017, 03:29:31 PM
One more animation - area around Wrangel Island 2017 vs 2016 (same day, Apr 25). Images: Worldview. And current forecast shows next 7 days significantly warmer than usual over ESS.
Title: Re: The 2017 melting season
Post by: Shared Humanity on April 25, 2017, 03:37:06 PM
All of these images and animations are telling the same story. As the ice begins to move it crumbles into a mess of small flows. While this is occurring where the ice is the thinnest, I believe there is something else it is telling us. These persistently warm winters with this past winter being the worst has resulted in dramatically weaker ice, regardless of thickness. Mobile and fragile is the new Arctic and it is never going away.
Title: Re: The 2017 melting season
Post by: iceman on April 25, 2017, 04:07:14 PM
A year on year look at the Beaufort. Far less cracks. Give it time though I suppose.
Yes but the area of open water was completely crazy. This year it looks more normal and its been really cold.
   ....
I dare say the only year the situation in the Beaufort is better than is last year. 2012 and 2013 are also available in Worldview, but early 2013 is rotated 90 degrees compared to the rest of the dataset. Both of them had even less cracks, and 2013 looked like this year did before high pressure moved in to Beaufort. However, 2012's cracks were very long, oriented longitudinally, and contained open water between them.

Beaufort and the adjoining part of CAB seem in fairly good shape on area/extent and ice mechanics, and will likely remain so into mid-May.  Volume indicators are more mixed, but probably worse if you take into account the Gyre effect (or lack thereof).  Whether it ends the season high or low depends partly on the degree and timing of melt ponding.  I'll guess low.
     An oddity: Beaufort might open up from the Chukchi side this year.
Title: Re: The 2017 melting season
Post by: Bob Wallace on April 25, 2017, 08:50:30 PM


(http://neven1.typepad.com/.a/6a0133f03a1e37970b01bb098cffa0970d-pi)

I think this is a year in which smart money does not bet against the first summer Arctic sea ice melt out.

I think there's a very good chance that once ice gets below 3,000 km3 we're likely to see very accelerated melting of ice which is not jammed against land masses.  In an ocean which is largely ice free the remaining pieces of ice are likely to move around rapidly, leaving the pockets of protective cold water that surrounds them.  And we'll see accelerated flushing out of the Central Basin into the killing fields. 



Title: Re: The 2017 melting season
Post by: bbr2314 on April 26, 2017, 12:03:33 AM
Snow extent back up to +1SD, surprisingly... and volume is just beyond!

(https://www.ccin.ca/home/sites/default/files/snow/snow_tracker/nh_sce.png)

(https://www.ccin.ca/home/sites/default/files/snow/snow_tracker/nh_swe.png)
Title: Re: The 2017 melting season
Post by: jai mitchell on April 26, 2017, 12:21:03 AM


([url]http://neven1.typepad.com/.a/6a0133f03a1e37970b01bb098cffa0970d-pi[/url])

I think this is a year in which smart money does not bet against the first summer Arctic sea ice melt out.

I think there's a very good chance that once ice gets below 3,000 km3 we're likely to see very accelerated melting of ice which is not jammed against land masses.  In an ocean which is largely ice free the remaining pieces of ice are likely to move around rapidly, leaving the pockets of protective cold water that surrounds them.  And we'll see accelerated flushing out of the Central Basin into the killing fields.


Those are good points and probably right.  I have said similar things but expect the impact to become much more rapid once we drop below 1,000 km3.  I am currently projecting a minimum of 1,750 km3 +/- 1,500 km3.   From here on out it all depends on the weather and I am starting to see some projections of significant WV intrusion on the Pacific Side that is reminiscent of the early 2013 season.  We will see if it holds up or not.
Title: Re: The 2017 melting season
Post by: Thomas Barlow on April 26, 2017, 05:44:23 AM
It might be interesting if they didn't include the years from 2010 onwards in their "Mean Volume".

Does anyone have the data skills to create such a chart? ... with only 1979-2010 included for the average (black-dotted line).
It would be interesting to see the difference in the chart, caused by the last several low-volume years.

Here's a crack with a line for 1979-2010 added.

We'll see what September 2017 brings us, but it seems clear that there is a good chance that we are about to find out if the Arctic summer melts ice 'volume' or if it melts 'extent'.
I'd guess both. If less thick ice becomes the norm, as it may be heading for this year, then more open areas by August 1st are likely. After that, extent could drop precipitously.
Title: Re: The 2017 melting season
Post by: Hyperion on April 26, 2017, 07:24:58 AM
Bering Strait is like washing machine, Apr 22 - Apr 24, Worldview.
Yes. Absolutely.
I noticed last night the motion of the bergs there had re ersed on suomi 24th imge compared to 23rd. It appears to have gone into flush mode again. Motion is still westward on the coast near wrangel. I wish someone with the image analysis tools and skills like Ateam could graph the mean basin sea level atmospheric pressure so we can map the correlation with the current behaviour. The wind in the Atlantic Quadrant has ceased its pernicious outward surge Assistance and a tidal back wash wave is probably capable of traversing the span to Bering in 6-8 hours. I'll try and research that later. The admiral is on a shore excursion at present to purchase equipment an vitals and only has hiz phone for egossipin.
Title: Re: The 2017 melting season
Post by: Lord M Vader on April 26, 2017, 09:19:00 AM
ECMWF 00z operational run depicts a bad setup for the ice by Day 9-10 with a big HP dome over Greenland and a LP over Kara Sea ---> lot of ice transport through Fram if verified!
Title: Re: The 2017 melting season
Post by: DuraSpec on April 26, 2017, 10:18:15 AM
Water equivalent volume of snow for the northern hemisphere peaked at about (really roughly) 500 km3 above the norm based on the graph from bbr2314. This will melt into waters that are relatively warm and flow towards the ocean collecting thermal energy along the way.

This seems to me as a very large (in my very naive opinion) thermal mass heading into the ocean that didn't exist to this extent in the past.

Evaporating open ocean waters (ice free area) increases the humidity and water load in the air leading to more snow (water equivalent snow mass).

In relation to the melting season, this seems to me like an important energy transport variable because of the large volume of water heating up on the land and running into the sea.

Is this an appropriate thought? And what are the energy differences in transported energy into the ocean do to this effect based on the change in the volume of snow/water?

There is a lot of land mass in the northern hemisphere...

In a rough percentile estimate, what percentage of effect does this have to the overall melting season compared to the albedo of open ocean waters?

... and volume is just beyond!


(https://www.ccin.ca/home/sites/default/files/snow/snow_tracker/nh_swe.png)
Title: Re: The 2017 melting season
Post by: Bill Fothergill on April 26, 2017, 10:57:32 AM
...
Either way, and from the graphs posted earlier, it is clear that sea ice 'volume' is on a persistent and potentially catastrophic decline. 2017 is especially noteworthy, because of the current record low PIOMAS numbers.
...
We'll see what September 2017 brings us, but it seems clear that there is a good chance that we are about to find out if the Arctic summer melts ice 'volume' or if it melts 'extent'.

It's an interesting quandary, isn't it Rob?

I was playing about with the monthly figures for PIOMAS, NSIDC Area and NSIDC extent in order to see if I could tease out any clue as to which might be least susceptible to "noise". To do so, I used a simple linear regression in order to obtain a value for the trend, and then subsequently calculated the residuals.

I then compared the Standard Deviation of the residuals with the trend. It's obviously more than a bit crude and simplistic, but my thinking was the higher the value of this ratio, the less time it takes for the genuine underlying trend to emerge from any noise distortion (i.e. natural variability).

The September numbers were...

PIOMAS: Trend = -324 cubic kms per annum, SD of residuals = 1,434 cubic kms

NSIDC area: Trend = -79k sq kms per annum, SD of residuals = 441k sq kms

NSIDC extent: Trend = -87k sq kms per annum, SD of residuals = 550k sq kms


That produces ratios of...
PIOMAS 0.226
NSIDC area 0.18
NSIDC extent 0.159

A possibly more meaningful way of expressing these values might be in terms how many years worth of each trend equates to 2 times the relevant Standard Deviation (i.e. the old 95% confidence level). That comes out as 9 years, 11 years and 12 and a half years respectively.

Using that simplistic approach would suggest that PIOMAS will be the better indicator, as it makes an earlier emergence from the natural variability.

The PIOMAS Daily Arctic Ice Volume graph from Wipneus that you posted is excellent at showing how perilous the end-of-melt-season has become, but, looking at the March-April-May part, it also serves to show that we are still a long way from a totally ice free Arctic. On the 1979-2001 average, the value for the beginning of April is ~ 29,700 cubic kms. The equivalent 2017 value stands at ~ 20,4000 cubic kms - a drop of just over 9,000 cubic kms over a (notional) period of 27 years.

The attached diagrams below show PIOMAS projections for September and for the March-May average volume. If one projects a 2nd order polynomial trend line, the September figure effectively goes to zero in 5 years, but, with a linear projection, this is delayed until about 2032.

The maximum volume is typically attained in April, but with the March-May average and using a 2nd order polynomial fit, the trend does not go to zero until 2050. In fact, the March-May average would still be around 10,000 cubic kms in 20 years time. (Using a linear fit, this trend does not reach zero until almost the end of the 21st Century.)

Anyway, getting back to the melting season aspects, we both know how poor the correlation is for area/extent when the interval gets more than a couple of months. There are various references in the scientific literature to a decorrelation period of just 2 or 3 months for area/extent.

However, using Excel's CORREL, the correlation coefficient between the PIOMAS mean March-April-May residuals and the September residuals (1979-2016) comes out at an interesting 0.65
Title: Re: The 2017 melting season
Post by: dnem on April 26, 2017, 01:36:41 PM
The changes we are observing in the arctic are the result of continual and growing perturbation from a roughly equilibrium state, caused by building AGW.  This perturbation has caused measurable and growing changes in many monitoring variables (extent, area, volume) over the past few decades.  I think Bill's analysis relies on the assumption that the rate of change of the perturbation over time going forward will remain constant.  I am not convinced this is a valid assumption.  I believe the rate of change of the cumulative forcings may well change at an increasing rate in the future.

Past performance is not a reliable predictor of future performance.
Title: Re: The 2017 melting season
Post by: dj on April 26, 2017, 01:37:13 PM
Question:  I have used the PIOMAS volume and NSIDC area monthly averages to calculate thickness.  Has anyone noted the shift in timing of when maximal Arcic ice thickness occurs?  Or is this in some way an artifact that results from development of melt ponds early in the season?
I ask because there appears to be a dramatic shift from Sept/August to May/June.
I attribute this to a shift in the ratio of FYI to MYI with the first year ice rapidly melting off earlier.

First figure: Arctic Ice Thickness (m) reported as a stock with open, close, high, low.  Black = loss, White = Gain.
Second figure: Month of maximal thickness of Arctic Ice (from Sept to Aug).

Title: Re: The 2017 melting season
Post by: Buddy on April 26, 2017, 02:27:39 PM
Has anyone noted the shift in timing of when maximal Arctic ice thickness occurs?  Or is this in some way an artifact that results from development of melt ponds early in the season?
I ask because there appears to be a dramatic shift from Sept/August to May/June.
I attribute this to a shift in the ratio of FYI to MYI with the first year ice rapidly melting off earlier.

SWEET....great chart.....and nice "find".  As a non-scientific person.....I will be VERY curious to hear what the physics folks have to say.  That chart really does "gobsmack" me.  Clearly there is a "physical reason" for it.....and I can't wait to find out what it is.  I LOVE IT when people start asking questions....because they eventually lead to answers.

Title: Re: The 2017 melting season
Post by: VeliAlbertKallio on April 26, 2017, 02:42:38 PM
Although PIOMAS volume crossed to the lowest-ever category in mid-November 4 1/2 months ago, the substantial drops beneath any other have occurred in February and March. If May or June further pushes this gap we are really out, if the weathers became very cloudy, the gap would remain but close a bit and for those expecting an-ice-spectacular, this undoubtedly would be a disappointment. But the Arctic does have a certain degree of variability and unpredictability and one cannot be absolutely sure how much the elephant's trunk bends down. My gut feeling is that April and May would be very low just like February and March have been.



([url]http://neven1.typepad.com/.a/6a0133f03a1e37970b01bb098cffa0970d-pi[/url])

I think this is a year in which smart money does not bet against the first summer Arctic sea ice melt out.

I think there's a very good chance that once ice gets below 3,000 km3 we're likely to see very accelerated melting of ice which is not jammed against land masses.  In an ocean which is largely ice free the remaining pieces of ice are likely to move around rapidly, leaving the pockets of protective cold water that surrounds them.  And we'll see accelerated flushing out of the Central Basin into the killing fields.


Those are good points and probably right.  I have said similar things but expect the impact to become much more rapid once we drop below 1,000 km3.  I am currently projecting a minimum of 1,750 km3 +/- 1,500 km3.   From here on out it all depends on the weather and I am starting to see some projections of significant WV intrusion on the Pacific Side that is reminiscent of the early 2013 season.  We will see if it holds up or not.
Title: Re: The 2017 melting season
Post by: jai mitchell on April 26, 2017, 02:43:00 PM
the average thickness graph is interesting and I have wondered for many years what it is actually telling us since it is really a function of two dynamic metrics, sea ice extent and volume.  I believe that your interpretation is correct that the loss of multi-year ice has skewed the distribution curve after 2007 and especially after 2012.  However, it should be noted that after a rapid collapse of sea ice extent, the average thickness would go up! Which on its face makes it kind of pointless to track, though there may be some interesting useful data there that I am not seeing.
Title: Re: The 2017 melting season
Post by: crandles on April 26, 2017, 03:12:16 PM
Question:  I have used the PIOMAS volume and NSIDC area monthly averages to calculate thickness.  Has anyone noted the shift in timing of when maximal Arcic ice thickness occurs?  Or is this in some way an artifact that results from development of melt ponds early in the season?
I ask because there appears to be a dramatic shift from Sept/August to May/June.
I attribute this to a shift in the ratio of FYI to MYI with the first year ice rapidly melting off earlier.

First figure: Arctic Ice Thickness (m) reported as a stock with open, close, high, low.  Black = loss, White = Gain.
Second figure: Month of maximal thickness of Arctic Ice.


Monthly figures are not good averages of the whole month often equate to value around 21/22nd of month. Better to do it with daily values. Using NSIDC extent I get

Max thickness Year day no. PIOMAS volume
2.318364396   1988 154  28.859
2.289274106   1989 138  29.582
2.288970221   1990 264  13.759
2.261284793   1991 162  27.703
2.25912203   1992 157  28.047
2.261604054   1993 152  28.114
2.254532152   1994 160  27.733
2.160511824   1995 145  26.678
2.118136706   1996 152  26.464
2.257689178   1997 152  27.747
2.197949979   1998 159  26.804
2.151437466   1999 174  23.498
2.09246973   2000 157  25.231
2.105114887   2001 167  23.912
2.110257681   2002 154  25.551
2.044730392   2003 131  26.696
2.045465942   2004 152  24.474
2.006957997   2005 154  23.652
1.95871678   2006 155  22.774
1.826859136   2007 146  22.527
1.894886364   2008 140  24.012
1.842512479   2009 153  22.147
1.743161214   2010 138  22.112
1.686625805   2011 134  21.464
1.695425125   2012 121  23.051
1.694907372   2013 138  21.866
1.753696131   2014 133  22.300
1.859662816   2015 128  23.826
1.795368353   2016 128  22.250

One year 1990 seems to have day of max pushed into Sept day 264. There is a local peak at day 155. Apart from this strange 1990 year that latest day is 174 23rd June.

Yes there is a noticeable trend towards earlier dates but it looks to me to be more like day 160 back to day 130.  Approx 30 days over 28 year period. That seems more in accordance with:

(http://psc.apl.uw.edu/wordpress/wp-content/uploads/schweiger/ice_volume/Bpiomas_plot_daily_heff.2sst.png)

I started in 1988 due to every other day gaps prior to this in NSIDC extent.

Using area will probably make the September peak more prominent and hence your different results but it looks to be confusing 2 different peaks in the pattern like 1990 is messed up using extent.
Title: Re: The 2017 melting season
Post by: dj on April 26, 2017, 03:34:19 PM
Question:  I have used the PIOMAS volume and NSIDC area monthly averages to calculate thickness.  Has anyone noted the shift in timing of when maximal Arcic ice thickness occurs?  Or is this in some way an artifact that results from development of melt ponds early in the season?
I ask because there appears to be a dramatic shift from Sept/August to May/June.
I attribute this to a shift in the ratio of FYI to MYI with the first year ice rapidly melting off earlier.

First figure: Arctic Ice Thickness (m) reported as a stock with open, close, high, low.  Black = loss, White = Gain.
Second figure: Month of maximal thickness of Arctic Ice.


Monthly figures are not good averages of the whole month often equate to value around 21/22nd of month. Better to do it with daily values. Using NSIDC extent I get

Max thickness Year day no. PIOMAS volume
2.318364396   1988 154  28.859
2.289274106   1989 138  29.582
2.288970221   1990 264  13.759
2.261284793   1991 162  27.703
2.25912203   1992 157  28.047
2.261604054   1993 152  28.114
2.254532152   1994 160  27.733
2.160511824   1995 145  26.678
2.118136706   1996 152  26.464
2.257689178   1997 152  27.747
2.197949979   1998 159  26.804
2.151437466   1999 174  23.498
2.09246973   2000 157  25.231
2.105114887   2001 167  23.912
2.110257681   2002 154  25.551
2.044730392   2003 131  26.696
2.045465942   2004 152  24.474
2.006957997   2005 154  23.652
1.95871678   2006 155  22.774
1.826859136   2007 146  22.527
1.894886364   2008 140  24.012
1.842512479   2009 153  22.147
1.743161214   2010 138  22.112
1.686625805   2011 134  21.464
1.695425125   2012 121  23.051
1.694907372   2013 138  21.866
1.753696131   2014 133  22.300
1.859662816   2015 128  23.826
1.795368353   2016 128  22.250

One year 1990 seems to have day of max pushed into Sept day 264. There is a local peak at day 155. Apart from this strange 1990 year that latest day is 174 23rd June.

Yes there is a noticeable trend towards earlier dates but it looks to me to be more like day 160 back to day 130.  Approx 30 days over 28 year period. That seems more in accordance with:

([url]http://psc.apl.uw.edu/wordpress/wp-content/uploads/schweiger/ice_volume/Bpiomas_plot_daily_heff.2sst.png[/url])

I started in 1988 due to every other day gaps prior to this in NSIDC extent.

Using area will probably make the September peak more prominent and hence your different results but it looks to be confusing 2 different peaks in the pattern like 1990 is messed up using extent.


Extent definitely would give a difference in dates, and due to how PIOMAS calculates thickness extent would not necessarily be appropriate
The average thickness is calculated for the PIOMAS domain by only including locations where ice is thicker than .15 m.

This may introduce some bias in PIOMAS' estimates?  Especially as the ice continues to get thinner with first year ice?
I guess one question should be, why is there such a distinct difference between PIOMAS's graph and the numbers reported.  I understand that differences in how things are calculated (cutoffs) would be in play.  Where does PIOMAS derive is numbers for extent/area?
Title: Re: The 2017 melting season
Post by: dj on April 26, 2017, 03:42:49 PM
I should point out, as confusing as it is - that for the second graph I used a single calendar year (Sept - Aug) instead of what is shown in the first graph (Sept to Sept), as I wanted to see if and when a shift occurred.
The first graph I made so that the students I teach could better "connect the dots" in that the start of one freeze/melt season was the finish of the prior freeze/melt season.

If that seems confusing - apologies.
Title: Re: The 2017 melting season
Post by: crandles on April 26, 2017, 03:50:59 PM
I guess one question should be, why is there such a distinct difference between PIOMAS's graph and the numbers reported.  I understand that differences in how things are calculated (cutoffs) would be in play.  Where does PIOMAS derive is numbers for extent/area?

I thought they came out pretty similar really:
For 2016 I have 1.8m, reading off PIOMAS graph I get around 1.78m
For 2004 I have 2.05m, reading off PIOMAS graph I get around 2.14m

given "The average thickness is calculated for the PIOMAS domain by only including locations where ice is thicker than .15 m.", yes it is surprising they are so close.


Title: Re: The 2017 melting season
Post by: dj on April 26, 2017, 03:56:41 PM
I guess one question should be, why is there such a distinct difference between PIOMAS's graph and the numbers reported.  I understand that differences in how things are calculated (cutoffs) would be in play.  Where does PIOMAS derive is numbers for extent/area?

I thought they came out pretty similar really:
For 2016 I have 1.8m, reading off PIOMAS graph I get around 1.78m
For 2004 I have 2.05m, reading off PIOMAS graph I get around 2.14m

given "The average thickness is calculated for the PIOMAS domain by only including locations where ice is thicker than .15 m.", yes it is surprising they are so close.

Could it be that I am following the freeze/melt season, and not the calendar year?
Plotting from Sept 2014 to Aug 2015 (for the second graph).
And yes indeed, I do think that is remarkably close.

Title: Re: The 2017 melting season
Post by: crandles on April 26, 2017, 04:08:59 PM

Could it be that I am following the melt season, and not the calendar year?
Plotting from Sept 2014 to Aug 2015?

Not at all sure I follow this question. Surely Jan 1 Piomas volume should be divided by Jan 1's area/extent and so on. I don't see why where the season ends matters.

Doing monthly is too coarse a resolution if you can get 2 peaks getting confused with each other. Near max extent and area are similar. At September area can be a lot less than extent so using area  gives a higher second peak and more chance of confusing the different peaks.
Title: Re: The 2017 melting season
Post by: dj on April 26, 2017, 04:12:40 PM
the average thickness graph is interesting and I have wondered for many years what it is actually telling us since it is really a function of two dynamic metrics, sea ice extent and volume.  I believe that your interpretation is correct that the loss of multi-year ice has skewed the distribution curve after 2007 and especially after 2012.  However, it should be noted that after a rapid collapse of sea ice extent, the average thickness would go up! Which on its face makes it kind of pointless to track, though there may be some interesting useful data there that I am not seeing.

I guess what I am wondering is that - with the thinning of the ice - is there a point where the average thickness will cross a threshold and allow for a rapid collapse?  For a variety of reasons?

Extent - I am not a fan of.  I agree that for a period of time there will be years of ice formation in the winter, and then ice loss in the summer.  And the debate about whether or not the Arctic is considered ice free will pointlessly rage on.  Environmentally, that ice is not the same and the changes will be significant - although one could argue they already are.


Title: Re: The 2017 melting season
Post by: dj on April 26, 2017, 04:18:22 PM

Could it be that I am following the melt season, and not the calendar year?
Plotting from Sept 2014 to Aug 2015?

Not at all sure I follow this question. Surely Jan 1 Piomas volume should be divided by Jan 1's area/extent and so on. I don't see why where the season ends matters.

Doing monthly is too coarse a resolution if you can get 2 peaks getting confused with each other. Near max extent and area are similar. At September area can be a lot less than extent so using area  gives a higher second peak and more chance of confusing the different peaks.

Yes but your January 1st 2014 is being compared with September - December 2014.
My September - December 2014 is being compared with January-August 2015.

Still there is a discrepancy between what I show and what PIOMAS shows.  After careful reading of PIOMAS it may be that they also do not included all areas that contain Ice and calculate only the thickness of the area that they calculate volume.  So, that may be one difference, in that the areas between PIOMAS and NSIDC are different.

Maybe back to the drawing board for me.   ;)
Title: Re: The 2017 melting season
Post by: crandles on April 26, 2017, 04:25:16 PM

I guess what I am wondering is that - with the thinning of the ice - is there a point where the average thickness will cross a threshold and allow for a rapid collapse?  For a variety of reasons?

If you have one foot in an ice bucket and one foot in near boiling water, does it matter whether you average temperature around you is a little too high or too low for comfort?

If there isn't all that much average thickness ice, why would you expect the tipping point threshold (if there is one) to be particularly noticeable in the average thickness measure?
Title: Re: The 2017 melting season
Post by: dj on April 26, 2017, 04:46:43 PM

I guess what I am wondering is that - with the thinning of the ice - is there a point where the average thickness will cross a threshold and allow for a rapid collapse?  For a variety of reasons?

If you have one foot in an ice bucket and one foot in near boiling water, does it matter whether you average temperature around you is a little too high or too low for comfort?

If there isn't all that much average thickness ice, why would you expect the tipping point threshold (if there is one) to be particularly noticeable in the average thickness measure?

I agree with you there - the average temperature is not going to be all that important.  We talk in terms of volume and extent.  Extent, is the least important but the thickness/volume is.  Any tipping point will be due to the loss of thick MYI versus FYI.
I am using some of this in classes, and stressing to my students that using averages is the appropriate method to do so (along with the standard other facors - variation, STD etc.).
Title: Re: The 2017 melting season
Post by: Wipneus on April 26, 2017, 06:56:26 PM
Question:  I have used the PIOMAS volume and NSIDC area monthly averages to calculate thickness. 

Not advisable. Since NSIDC area monthly averages do not include the area of the pole hole, the values vary with the satellite of the date.

If you want to use area (and not extent), either use CT-area (stopped updating last year) or my daily values:
https://sites.google.com/site/arctischepinguin/home/sea-ice-extent-area/data/nsidc_arc_nt_main.txt

Both make an assumption of the sea ice concentration within the pole hole from the measurements around it.
Title: Re: The 2017 melting season
Post by: marcel_g on April 26, 2017, 07:30:32 PM
The changes we are observing in the arctic are the result of continual and growing perturbation from a roughly equilibrium state, caused by building AGW.  This perturbation has caused measurable and growing changes in many monitoring variables (extent, area, volume) over the past few decades.  I think Bill's analysis relies on the assumption that the rate of change of the perturbation over time going forward will remain constant.  I am not convinced this is a valid assumption.  I believe the rate of change of the cumulative forcings may well change at an increasing rate in the future.

Past performance is not a reliable predictor of future performance.

This is a good point. I have another thought, but I'm not sure I can articulate it well. I'll give it a try: I also wonder if the attempt at statistical predicting like Bill's analysis is also missing the geographical consideration of the difference between the Arctic Basin and the peripheral seas, with respect to melting feedbacks. Since Hudson, Bering, Baffin, Okhotsk are all included in the volume and extent measurements.

Basically, in the beginning, the open water was really only in the peripheral seas by the end of the summer. Then the ice in the Arctic basin protected itself by preventing preventing solar energy gain (albedo), and by preventing wave action from disrupting the halocline/layering of water under the ice, and by keeping the relative humidity of the region low, allowing a lot of heat to escape once freezing season started up.

Now, (starting at some point around 2000?) every year there is a vast extent of open water within the Arctic basin, so the halocline/thermal layering of the ocean is disrupted, the water is gaining a lot more solar energy, the atmosphere is more humid, trapping even more energy. All this really affects the freezing season, reducing the volume of ice left to melt by the following melt season.

My question is, would we find out something interesting if did this kind of analysis by doing it on 2 different time periods: pre-Arctic basin open water, and post Arctic basin open water?

What happens to the trends if you have one for 1979-2000 and one for 2001-2016?

Title: Re: The 2017 melting season
Post by: JimboOmega on April 26, 2017, 07:36:52 PM

I agree with you there - the average temperature is not going to be all that important.  We talk in terms of volume and extent.  Extent, is the least important but the thickness/volume is.  Any tipping point will be due to the loss of thick MYI versus FYI.
I am using some of this in classes, and stressing to my students that using averages is the appropriate method to do so (along with the standard other facors - variation, STD etc.).

My feeling is that thickness matters less than everyone thinks it does, because it is the surface that interacts the most thermodynamically - it is the frozen area that reflects the light, that radiates heat off to space.  Especially right now, it seems things opening up (or not) has more to do with wind creating polynya than the thickness of the relevant ice and its resistance to melting.

Also the modeling behind thickness is a lot more imprecise - from what I've heard - than it is for extent (looking down from space and seeing ice is one thing, knowing how thick it is requires some assumptions).  There are a couple different volume numbers with very contrasting values (last I heard, anyway!)

Last year I heard a lot that a real cliff was coming, that the volume was so bad, we're so much worse off than 2012, etc. This year I'm not (automatically) buying it.

I think that the global climate implications of a the melting season are much more driven by extent than by volume, because that's what (via Albedo) controls how much extra heat would enter the system because of ice (or the lack thereof).

Last time I brought this up I asked people to make predictions based on the volume, IE, when would we see the results of the current volume in extent or other grossly visible things. I'd repeat that challenge again. 

Of course if you want to argue that weather trumps volume and thus you can't make any real predictions beyond a week or two, that's a valid assertion - but of course is contrary to the argument that average temperature matters less than volume.

It's also possible that each year we're getting a thinner pack and this is the year the thinness really does lead to a catastrophic extent/area drop. Do you think it is?  If it's not, how thin would it need to be for it to happen?
Title: Re: The 2017 melting season
Post by: johnm33 on April 26, 2017, 08:09:36 PM
"I guess what I am wondering is that - with the thinning of the ice - is there a point where the average thickness will cross a threshold and allow for a rapid collapse?  For a variety of reasons?"
When the ice no longer resists wave action, and is broken to the point where it flows like water, then I think we'll see a rapid collapse, from both melt and export. It looks possible this year, I suspect the ice is already melting from below, to a small degree, the thicker peices touching water thats just above 0C, yeilding a steady supply of easy to freeze fresh[er] water, rapidly repairing any cracks. Plus there's been plenty of snow around the arctic, some must have fallen on the ice raising it's freeboard and increasing the likelyhood of it moving through the water, and when the currents flow as recently by chukchi presenting little resistence. If it does reach that state the freshest top fraction will flow out with every tide and be pumped out under every high pressure system, replaced by inevitably warmer waters from the south.
Title: Re: The 2017 melting season
Post by: Lord M Vader on April 26, 2017, 09:12:20 PM
ECMWF 12z operational run is a hella scaring one!!! This is what the Arctic has to work with if the forecast run for Day 9-10 verifies!! Look at that monstrous high pressure dome covering virtually the whole Arctic!!!!

Would be a complete disaster, especially if it continues to linger for 1-2 weeks or so!! Courtesy: Tropical Tidbits/Lewi Cowan

(http://www.tropicaltidbits.com/analysis/models/ecmwf/2017042612/ecmwf_z500_mslp_nhem_11.png)
Title: Re: The 2017 melting season
Post by: rboyd on April 26, 2017, 10:05:48 PM
The Sensitivity of the Arctic Ocean Sea Ice Thickness and Its Dependence on the Surface Albedo Parameterization

ABSTRACT

In this study, the response of sea ice thickness to changes in the external forcing is investigated and particularly how this response depends on the surface albedo formulation by means of a one-dimensional coupled ocean–ice–atmosphere model. The main focus is on the thickness response to the atmospheric heat advection Fwall, solar radiation FSW, and amount of snow precipitation Sprec. Different albedo parameterization schemes [ECHAM5, CSIRO, and Community Climate System Model, version 3 (CCSM3)] representing albedos commonly used in global climate models are compared together with more simplified schemes. Using different albedo schemes with the same external forcing produces large differences in ice thickness. The ice thickness response is similar for all realistic albedo schemes with a nearly linear decrease with increasing Fwall in the perennial ice regime and with a steplike transition into seasonal ice when Fwall exceeds a certain threshold. This transition occurs at an annual-mean ice thickness of 1.7–2.0 m. Latitudinal differences in solar insolation generally leads to increasing ice thickness toward the North Pole. The snow response varies significantly depending on which albedo scheme is used. The ECHAM5 scheme yields thinner ice with Sprec, the CSIRO scheme gives ice thickness nearly independent of Sprec, and with the CCSM3 scheme the ice thickness decreases with Sprec. A general result is that the modeled ice cover is rather sensitive to positive perturbations of the external heat supply when it is close to the transition such that just a small increase of, for example, Fwall can force the ice cover into the seasonal regime.

http://journals.ametsoc.org/doi/pdf/10.1175/JCLI-D-12-00085.1 (http://journals.ametsoc.org/doi/pdf/10.1175/JCLI-D-12-00085.1)

If I understand correctly, this is saying that there is an ice-thickness / forcing threshold beyond which a move to seasonal sea ice occurs in a step-wise fashion - due to the albedo feedback mechanism. 

As the temperature differential between the Arctic and the rest of the Northern Hemisphere reduces, it becomes easier for warm air masses to enter the Arctic from the south (the Jet Stream weakens and becomes wavier). So the value of Fwall may increase, and the ice will have to be thicker to survive the melt season.

This of course does not take into account any mechanical changes in the ice as it thins, nor the possible mixing of the water column where there are areas of open water/thin ice.
Title: Re: The 2017 melting season
Post by: rboyd on April 26, 2017, 10:22:31 PM
Magnitude and pattern of Arctic warming governed by the seasonality of radiative forcing

Abstract

Observed and projected climate warming is strongest in the Arctic regions, peaking in autumn/winter. Attempts to explain this feature have focused primarily on identifying the associated climate feedbacks, particularly the ice-albedo and lapse-rate feedbacks. Here we use a state-of-the-art global climate model in idealized seasonal forcing simulations to show that Arctic warming (especially in winter) and sea ice decline are particularly sensitive to radiative forcing in spring, during which the energy is effectively ‘absorbed’ by the ocean (through sea ice melt and ocean warming, amplified by the ice-albedo feedback) and consequently released to the lower atmosphere in autumn and winter, mainly along the sea ice periphery. In contrast, winter radiative forcing causes a more uniform response centered over the Arctic Ocean. This finding suggests that intermodel differences in simulated Arctic (winter) warming can to a considerable degree be attributed to model uncertainties in Arctic radiative fluxes, which peak in summer.

2016 was the perfect case of this, where the albedo was highest in the Spring with the added energy being carried into the Fall season. We are running a bit behind of 2016 so far according to Nico Sun (details of his methodology on the Albedo Warming Potential Topic).

https://sites.google.com/site/cryospherecomputing/warming-potential/graphs
Title: Re: The 2017 melting season
Post by: Neven on April 26, 2017, 10:37:10 PM
Dear friends, can we please stay on-topic? There are various threads for discussing PIOMAS, volume, thickness, research.

Melting season.
Title: Re: The 2017 melting season
Post by: Archimid on April 26, 2017, 11:10:46 PM
rboyd: I would love to see more discussion on that first paper you posted. Maybe start a new thread, "The Fast Transition"?
Title: Re: The 2017 melting season
Post by: seaicesailor on April 27, 2017, 12:25:25 AM
For the next five days, high pressure system coming back to the pacific side of Arctic, but ACNFS predicts very modest intensity of induced clockwise drift.
Pressure gradients not as intense as in the first half of April? We'll see how it goes.
Title: Re: The 2017 melting season
Post by: dj on April 27, 2017, 01:22:21 AM
Thank you for the comments and the further resources to explore.

And thank you Wipneus for identifying the weakness (incorrectness) of my comparison, and providing the corrected data. 

Neven, apologies for picking the incorrect place to post this.
Title: Re: The 2017 melting season
Post by: Meirion on April 27, 2017, 04:43:13 AM
You know when the "arctic sea ice isn't really melting" crowd start saying "but why should we trust the sea-ice concentration map" - or whatever - and you want to say - "well I've just seen it". Well...

I just flew London to Los Angeles and the routing looked interesting. Sadly there was thick cloud over the Fram but it cleared over western Greenland and you could see open sea with not a hint of ice for miles along the coast. Halfway across the channel to Baffin Island a very thin sheet of ice lay on the sea with the occasional iceberg ploughing through it and the water not refreezing behind. More ice may drift south but the ice that is there will not last long. Into Hudson Bay parts of the north had more open water than appears on the sea ice concentration map. There was also a lot of 60-70% concentration ice. In the middle the ice was heavily cracked but looked thicker as if would still last a few more weeks. In short, at least for that 100 mile wide slice of the arctic and sub arctic, if any sceptics are reading, my eyes broadly confirmed the concentration map.
Title: Re: The 2017 melting season
Post by: Rob Dekker on April 27, 2017, 06:30:54 AM
dj, I would suggest you re-post your entry (maybe with the responses from Wipneus and crandles) in a new thread, or use the existing thread on PIOMAS :
http://forum.arctic-sea-ice.net/index.php/topic,119.1600.html (http://forum.arctic-sea-ice.net/index.php/topic,119.1600.html)

Given that several people responded to you post, and there is no immediate answer, your findings are worth a discussion. Also, I have some thoughts on the issue I would like to share.
But not here in the "melting season" thread.
Title: Re: The 2017 melting season
Post by: Cid_Yama on April 27, 2017, 06:35:04 AM
Perception and interpretation is influenced by what you have to lose.  We have a lot of (relatively, I'm 73) young people on here that would rather not accept catastrophe until it happens.

It's ok.  Let them believe what they will.  Reality will come soon enough.  Not like there is anything that can or will be done about it.

   
Title: Re: The 2017 melting season
Post by: Rob Dekker on April 27, 2017, 06:42:03 AM
However, using Excel's CORREL, the correlation coefficient between the PIOMAS mean March-April-May residuals and the September residuals (1979-2016) comes out at an interesting 0.65

R=0.65 is not bad at all for a March predictor of September SIE.
But what is the SD over the residuals ? And is it better than the SD of 550 k km^2 from the simple linear trend ?
Either way, we should probably take this discussion elsewhere.
You want to take it to the PIOMAS thread ?
Title: Re: The 2017 melting season
Post by: dj on April 27, 2017, 07:46:19 AM
dj, I would suggest you re-post your entry (maybe with the responses from Wipneus and crandles) in a new thread, or use the existing thread on PIOMAS :
[url]http://forum.arctic-sea-ice.net/index.php/topic,119.1600.html[/url] ([url]http://forum.arctic-sea-ice.net/index.php/topic,119.1600.html[/url])

Given that several people responded to you post, and there is no immediate answer, your findings are worth a discussion. Also, I have some thoughts on the issue I would like to share.
But not here in the "melting season" thread.


Done at the PIOMAS Update (the link you included).
Title: Re: The 2017 melting season
Post by: Bill Fothergill on April 27, 2017, 10:50:53 AM
Thank you for the comments and the further resources to explore.

And thank you Wipneus for identifying the weakness (incorrectness) of my comparison, and providing the corrected data. 

Neven, apologies for picking the incorrect place to post this.

As Wipneus correctly (natch!  ;)) pointed out, the NSIDC monthly values for area have a "pole hole". (NB This only applies to area; for extent, they work on the basis that the pole hole is fully covered by ice with >15% concentration, and therefore this is already included in the published numbers.)

I utilise the NSIDC monthly numbers in several of my tables, but, before using any of the values, the following offsets are added...

Nov 1978 - Jun 1987      1.19   million sq kms   
Jul 1987 - Dec 2007      0.31   million sq kms   
Jan 2008 - present      0.029 million sq kms   

(NBB By doing this, I am therefore assuming the pole hole is 100% ice covered. That's becoming a highly questionable assumption, but the current pole hole size is so small, it doesn't overly affect things.)

See...
http://nsidc.org/data/docs/noaa/g02135_seaice_index/#pole-hole-size (http://nsidc.org/data/docs/noaa/g02135_seaice_index/#pole-hole-size)


 
Title: Re: The 2017 melting season
Post by: Bill Fothergill on April 27, 2017, 11:00:09 AM
Dear friends, can we please stay on-topic? There are various threads for discussing PIOMAS, volume, thickness, research.

Melting season.
Sorry if it was my post #949 which was initially responsible for the OT seque.

I had been trying to provide a simplistic analysis concerning which metric (PIOMAS/extent/area) might be the better indicator for the forthcoming - and potentially horrific - melt season.

I'll copy #949 over to the PIOMAS thread, and will provide any relevant responses over there.
Title: Re: The 2017 melting season
Post by: Thomas Barlow on April 27, 2017, 02:01:05 PM
This mixes (colors) concentration with sea-ice thickness maps, so the blue areas (not deeper purples, or reds and blacks) show where the vulnerability is, being both thinner, and slightly lower concentration. Reds, blacks, and deeper purple, show thicker, more concentrated ice.
Title: Re: The 2017 melting season
Post by: Sarat on April 27, 2017, 04:54:24 PM
Interesting graphic, really looks like where ice is close to 100% concentration it's thinner and areas with thicker ice are more fractured.
Title: Re: The 2017 melting season
Post by: romett1 on April 27, 2017, 08:45:26 PM
Sea ice area over Bering Sea is lowest in recent years (black line, about 150,000 km²). In 2012 it was about 600,000 km² at the same time and around 950,000 km² second week of April 2012 (orange line). I'm looking this Wipneus site quite often, all other regions also updated daily, but maybe for new forum readers there is good overview here (third one): https://sites.google.com/site/arctischepinguin/home/amsr2/grf
Title: Re: The 2017 melting season
Post by: rboyd on April 27, 2017, 09:07:51 PM
Archimid - I started the The Fast Transition topic.
Title: Re: The 2017 melting season
Post by: Tigertown on April 28, 2017, 05:42:24 AM
Looking a little haggard.
(http://)
Title: Re: The 2017 melting season
Post by: romett1 on April 28, 2017, 06:57:55 AM
Looking a little haggard.

Indeed, we have talked about Bering, Chukchi and ESS, but concentration maps over Atlantic side are not better. Here is another example this morning, lot of cracks near North Pole, also visible on Worldview. Image: ftp://ftp-projects.cen.uni-hamburg.de/seaice/AMSR2/Arc_latest_yesterday_AMSR2_3.125km.png
Title: Re: The 2017 melting season
Post by: Hyperion on April 29, 2017, 03:41:45 AM
 Three Animations for the eight days 21 april to 28th.

The Beaufort butter-churn,

The Chukchi Icecream maker,

And the East Siberian Sea Berg-Grinder.
Title: Re: The 2017 melting season
Post by: Tigertown on April 29, 2017, 05:58:33 AM
Comparison for same date but differing charts
CLICK TO ACTIVATE
Zoom for better view.
(http://)
Title: Re: The 2017 melting season
Post by: Tor Bejnar on April 29, 2017, 07:26:47 AM
I've copied 5 of the extent graphs from the Regional Graphs page (https://sites.google.com/site/arcticseaicegraphs/regional): three have lots of ice and two have record(?) low ice.
 
The Barentsz Sea (Dutch spelling, and the guy was Dutch) is 'quite full' of ice - I don't have an opinion why.  The Greenland Sea is also 'quite full' - I think ice export from the Arctic Ocean is high (despite so much melting around Svalbard in the mid- and late winter).  Baffin / Newfoundland Bay is 'quite full' too - I think the lack of any sustained ice arch within Nares Strait has allowed much (thin) export of ice (ice that grows within the Strait over a 2 to 8 week period as it drifts southwards), and thin ice counts as extent. 

I note both the Bering Sea and Sea of Okhotsk have unseasonably low amounts of ice - I don't have an opinion why.

What opinions do other's have concerning these 5 regions?

(And yes, much of the ice is thinner than ever before at this time of year.)
Title: Re: The 2017 melting season
Post by: oren on April 29, 2017, 08:14:59 AM
Tor, I have noticed the same thing and it's been consistent for a while, I am sure it all has to do with Pacific to Atlantic movement, and in Baffin Nares to Atlantic movement.
Title: Re: The 2017 melting season
Post by: TerryM on April 29, 2017, 08:44:41 AM
Tor
FWIW I've always considered Greenland Sea ice to be ice that's already found it's way out of the arctic.


Terry
Title: Re: The 2017 melting season
Post by: Rob Dekker on April 29, 2017, 08:52:19 AM
Tor, oren,
I think it is too early in the season to draw much of a conclusion from these regional ice covers.
Note that the Barents, the Greenland sea and Baffin follow 2012 quite closely, and we all know what happened then later in the season.

I'm more concerned about 'volume'. If the ice is the Arctic is really as thin as PIOMAS suggests, the melting could start to accelerate once temperatures are above freezing.
Title: Re: The 2017 melting season
Post by: oren on April 29, 2017, 09:24:45 AM
Rob, I totally agree.
Title: Re: The 2017 melting season
Post by: Bill Fothergill on April 29, 2017, 10:02:37 AM
Tot, oren, Terry, Rob,

I think there has been some gibbering in Flatland recently concerning the amount of ice around Newfoundland. One suspects that this is export related, and that any such ice is basically "dead man walking".
Title: Re: The 2017 melting season
Post by: DavidR on April 29, 2017, 10:50:34 AM
Tot, oren, Terry, Rob,

I think there has been some gibbering in Flatland recently concerning the amount of ice around Newfoundland. One suspects that this is export related, and that any such ice is basically "dead man walking".
The ice around Newfoundland is almost certainly the result of collapsing glaciers not sea ice. Its one area where an increase in 'sea ice' can be expected as glacier collapse in Greenland becomes more prevalent.
Title: Re: The 2017 melting season
Post by: Gray-Wolf on April 29, 2017, 11:28:42 AM
I do think the storm surge, associated with the berg flushing we heard about, is behind the re-floating of a lot of beached glacier ice/rubble and this floated off melange may be behind the ice around the Newfoundland coast?

As noted above the collapse , and retreat up valley, will lead to ever more 'large ice' beaching on its way to the Atlantic. Should last winter be showing us the WACCy weather we should expect then we should also be accepting of a flushing mechanism into the North Atlantic and long detours for ocean traffic avoiding the bergs ( putting lots more crap into the atmosphere from their smoke stacks).
Title: Re: The 2017 melting season
Post by: nukefix on April 29, 2017, 12:28:41 PM
The ice around Newfoundland is almost certainly the result of collapsing glaciers not sea ice. Its one area where an increase in 'sea ice' can be expected as glacier collapse in Greenland becomes more prevalent.
Why would glacier mass-loss cause that? Something to do with the extra meltwater?
Title: Re: The 2017 melting season
Post by: Jim Hunt on April 29, 2017, 12:46:19 PM
Something to do with the extra meltwater?

I assume from his quotation marks that David is implying that much of the extra "sea ice" around Newfoundland is actually ex "glacier ice".
Title: Re: The 2017 melting season
Post by: Bill Fothergill on April 29, 2017, 02:15:38 PM
TotTor, oren, Terry, Rob,  {Oops, just noticed the fat-finger syndrome}

I think there has been some gibbering in Flatland recently concerning the amount of ice around Newfoundland. One suspects that this is export related, and that any such ice is basically "dead man walking".
The ice around Newfoundland is almost certainly the result of collapsing glaciers not sea ice. Its one area where an increase in 'sea ice' can be expected as glacier collapse in Greenland becomes more prevalent.

Yeah. My first response when I saw the comment(s) about ice in the Newfoundland region was that it was almost certainly a mixture of (a) detritus that had calved from a glacier front, and (b) an artefact caused by freshwater lensing as a result of melt.

However, there was also a remark about the thickness being at record level.

Having a totally useless memory, I cannot recall the article source. HOWEVER, I pretty sure it would have been something associated with a very recent entry on the "Arctic Image of the Day" thread. There was a photo (#835) on that thread of a grounded 'berg off the coast near Ferryland. It was just after seeing that image, that I read (somewhere) about there being sea ice of record thickness near Newfoundland.

Being in an unusually generous mood, I was prepared to accept the description as having some basis in fact - as opposed to the normal Flatland bollocks. As I mentioned in the original post, if that genuinely is sea ice - as opposed to glacial ice - then it has come from further north, and is on its way to a rather rapid phase change.

Perhaps I was being overly generous. (Perhaps there is no "perhaps" about it?)
Title: Re: The 2017 melting season
Post by: Thomas Barlow on April 29, 2017, 02:25:53 PM
Interesting graphic, really looks like where ice is close to 100% concentration it's thinner and areas with thicker ice are more fractured.

My take on it is that there are areas of thick, concentrated ice, and thinner ice. The Beaufort, for example, is relatively thick and relatively concentrated at this time compared to the main area of weakness which is towards the Russian (east) side, where the blue areas are thinner and less concentrated, and the intrusions of blue into the thicker areas should be note for concern, since those look more advanced than usual.  It's early days yet, but still gives an overall sense.
Title: Re: The 2017 melting season
Post by: iceman on April 29, 2017, 02:35:59 PM
   ....
I'm more concerned about 'volume'. If the ice is the Arctic is really as thin as PIOMAS suggests, the melting could start to accelerate once temperatures are above freezing.
Rob, I totally agree.

Likewise, even though volume is set to look a bit better as of April (PIOMAS model appears to track extent or area anomaly to some degree).
    It seems unusually tricky to assess pre-conditioning this year.  Volume is poorly distributed but concentration and compactness measures don't look too bad, and extent anomaly could continue improving through the first or second week of May.  The lack of early open areas at lower latitudes of the Arctic (notably excepting Chukchi, but that's small) also helps on the insolation count.
    My sense is that the season will hinge on which exerts the greater influence on volume: concentration or melt ponding.  Western Beaufort and adjoining CAB might be an early tell.
Title: Re: The 2017 melting season
Post by: Niall Dollard on April 29, 2017, 02:40:13 PM
Regarding this melt season and what the extent min will be like this year, at Jan 1st I was fully expecting to see a new record set this year (given the state of the ice last September). Now I'm not so sure. A few things of note, that have been mentioned already in various threads on the forum:

- NH Snow cover is up this spring
- Little opening yet in the Beaufort (compared to last year)
- The Kara Sea ice "rally" during the month of April, after opening considerably at the end of March.
- Practically no melt so far in Greenland.

All of these help buy time, keep the albedo up, as we head towards peak insolation. Even the snow papering over the cracks, serves to help.

June will tell a lot and whether we have an LP dominated cloudy summer. If this is to be the pattern we could be in a prolonged situation where the "rubble" remains, sloshing about for several summers to come. Thickness and PIOMAS numbers continuing to decline but with the rubble/veneer continuing to keep the extent numbers up circa 3 to 4 million square kilometres. It could be a while yet before we see a blue ocean summer.

As I believe there are a lot of super sensitive (and equally super sensible ! ) contributors to this forum, let me clarify that I do not believe that we are in for anything that you could remotely call a "recovery".I have an aversion to even typing that word!  :)

I fully subscribe to the anthropogenic global warming theory. One thing you should not do though is trivialise the Arctic. It will always be two steps back one step forward and visa versa   
Title: Re: The 2017 melting season
Post by: Tor Bejnar on April 29, 2017, 04:31:27 PM
TotTor, oren, Terry, Rob,  {Oops, just noticed the fat-finger syndrome}
...
...
...
You made me feel young (very young) again!  :)
Title: Re: The 2017 melting season
Post by: Bill Fothergill on April 29, 2017, 05:09:57 PM
...
You made me feel young (very young) again!  :)

All part of the service  :-[
Title: Re: The 2017 melting season
Post by: Shared Humanity on April 29, 2017, 05:13:39 PM
I've copied 5 of the extent graphs from the Regional Graphs page (https://sites.google.com/site/arcticseaicegraphs/regional): three have lots of ice and two have record(?) low ice.
 
The Barentsz Sea (Dutch spelling, and the guy was Dutch) is 'quite full' of ice - I don't have an opinion why.  The Greenland Sea is also 'quite full' - I think ice export from the Arctic Ocean is high (despite so much melting around Svalbard in the mid- and late winter).  Baffin / Newfoundland Bay is 'quite full' too - I think the lack of any sustained ice arch within Nares Strait has allowed much (thin) export of ice (ice that grows within the Strait over a 2 to 8 week period as it drifts southwards), and thin ice counts as extent. 

I note both the Bering Sea and Sea of Okhotsk have unseasonably low amounts of ice - I don't have an opinion why.

What opinions do other's have concerning these 5 regions?

(And yes, much of the ice is thinner than ever before at this time of year.)

I believe, as others have said, that the current, relatively high extent and area in the Barents and Greenland Sea is due to a new dynamic, the increased mobility of Arctic sea ice. This is the result of a number of changes in the Arctic, thinner ice, stormier weather and warmer surface waters (intrusion and upwelling?), figuring as three of the most prominent. In the dead of winter this spreading of the ice cover first results in increased extent, allowing for a subsequent increase in area as freezing causes this dispersed ice to be stitched together with very thin FYI. This process is in play not only in the Barents and Greenland Seas but also is vividly present in the CAB in the areas which have transported ice into these seas throughout the winter by a succession of storms (the cyclone cannon) from the North Atlantic into the CAB. This area of the CAB also sports remarkably thin ice, comprised mainly of highly mobile early season FYI that has been continuously stitched together with newer, much thinner FYI. Early in the freeze season, we all remarked how quickly this transported ice was melting as it encountered the warm waters around Franz Josef and Svalbard. As the freeze season deepened this ice began to survive. It won't for long, I fear. Nor will the areas of the CAB that have been transporting ice into these seas.
Title: Re: The 2017 melting season
Post by: romett1 on April 29, 2017, 05:25:58 PM
I thought maybe these two bigger blocks survive bit longer near Wrangel Island, Chukchi Sea. But as the first block hit the coast yesterday, it just disintegrated into smaller pieces. Images: Worldview, Apr 26 - Apr 28.
Title: Re: The 2017 melting season
Post by: Shared Humanity on April 29, 2017, 05:54:44 PM
We can clearly see the effects of increased sea ice mobility during the melt season as there is a 4 decade long trend of increasing dispersion at minimum. One of the most interesting characteristics of this trend is the step behavior we see. There are three distinct shifts upward in dispersion, occurring in 1989, 1998 and 2008. Each of these occurred after devastating melt seasons wiped out a huge amount of MYI. Unless we begin to see seasonal increases in MYI (I don't think this will occur.), this new mobility has become a persistent feature.

When I first created this dispersion chart, I realized it would be fascinating to see how dispersion behaved throughout the melt and freeze season, essentially charting this weekly throughout the year. It would be particularly interesting to see what changes occurred at the point when these MYI killing seasons happened. Alas, I haven't had the time.
Title: Re: The 2017 melting season
Post by: Shared Humanity on April 29, 2017, 06:13:49 PM
Paradoxically, the very low SIE in the Bering and Sea of Okhotsk is also the result of thinner ice, stormier weather and warmer surface waters (intrusion and upwelling?). That this results in anomalously low SIE while the opposite occurs on the Atlantic side is because these seas are not replenished by ice transported from the CAB.
Title: Re: The 2017 melting season
Post by: Tor Bejnar on April 29, 2017, 06:59:16 PM
Very interesting pair of graphs, SH. (Thanks!)  Do you 'see anything' if you plot 'difference' vs. 'ratio'?  Is it basically the same if you use '% difference' [(A-B)/B] instead of 'ratio' [A/B]? (If you don't respond, I'll know it's because you don't have time - you already said so  :) )
Title: Re: The 2017 melting season
Post by: Shared Humanity on April 29, 2017, 08:31:17 PM
Very interesting pair of graphs, SH. (Thanks!)  Do you 'see anything' if you plot 'difference' vs. 'ratio'?  Is it basically the same if you use '% difference' [(A-B)/B] instead of 'ratio' [A/B]? (If you don't respond, I'll know it's because you don't have time - you already said so  :) )

I still have the data I used for this chart. Would be easy to do. Maybe today.
Title: Re: The 2017 melting season
Post by: Cate on April 29, 2017, 10:52:43 PM
Re current Newfoundland ice: there is certainly a lot of hilarious mileage being made on that Ferryland iceberg. All looks like typical media hype to me. 

The most recent Canadian Ice Service "stages of development" chart shows that the vast majority of ice on our NE coast is first-year ice of various thicknesses. This is in the context of bergy water in the entire Labrador Sea and coastal Newfoundland environs. So, current ice around Newfoundland is a combo of both sea ice and glacial ice----and 'twas ever thus, as far as I can recall. Nothing so remarkable about this year at all.

When I was a child in the 1960s, ice forecasts on the wireless would routinely mention "blue ice" as part of the mix: thus, "concentration 4/10ths grey ice, 1/10 blue ice". I was always told that blue ice came from glaciers, and was therefore different from all the surrounding pack ice, which incidentally forms the whelping grounds of the harp and hood seals.

The blue ice is the stuff that sparkles in your G&T, btw. Tourism operators will not tell you this. ;)
Title: Re: The 2017 melting season
Post by: magnamentis on April 29, 2017, 11:06:39 PM
I've copied 5 of the extent graphs from the Regional Graphs page (https://sites.google.com/site/arcticseaicegraphs/regional): three have lots of ice and two have record(?) low ice.
 
The Barentsz Sea (Dutch spelling, and the guy was Dutch) is 'quite full' of ice - I don't have an opinion why.  The Greenland Sea is also 'quite full' - I think ice export from the Arctic Ocean is high (despite so much melting around Svalbard in the mid- and late winter).  Baffin / Newfoundland Bay is 'quite full' too - I think the lack of any sustained ice arch within Nares Strait has allowed much (thin) export of ice (ice that grows within the Strait over a 2 to 8 week period as it drifts southwards), and thin ice counts as extent. 

I note both the Bering Sea and Sea of Okhotsk have unseasonably low amounts of ice - I don't have an opinion why.

What opinions do other's have concerning these 5 regions?

(And yes, much of the ice is thinner than ever before at this time of year.)

thanks for the effort but beside that, there will always be regions with more and others with less ice than usual, reason is simple, once winds and/or currents pile up the ice on one side and empty the other side while during the next season and/or time span things turn around and depending on prevailing winds and currents the ice will pile up in another place.

this is, and no matter how much headwind i get, i think that these regional stuff is not useful, same applies to temps one season sibiria is colder and alaska is warmer and the other year or period of time it's vice versa and so on. nice to watch, interesting to know but has no value as to global warming and the overall development of arctic sea-ice IMO.
Title: Re: The 2017 melting season
Post by: Neven on April 29, 2017, 11:48:43 PM
this is, and no matter how much headwind i get, i think that these regional stuff is not useful, same applies to temps one season sibiria is colder and alaska is warmer and the other year or period of time it's vice versa and so on. nice to watch, interesting to know but has no value as to global warming and the overall development of arctic sea-ice IMO.

And that's why this is called the 2017 melting season thread, and not the 'global warming and the overall development of arctic sea-ice' thread. If you think a certain thread has no value, you simply look for one that has value for you. That's how an Internet forum works.
Title: Re: The 2017 melting season
Post by: Niall Dollard on April 30, 2017, 12:12:58 AM
thanks for the effort and no matter how much headwind i get, i think that these regional stuff is not useful has no value as to global warming and the overall development of arctic sea-ice IMO.

Well I for one like to keep a weather eye open on all events. Lake Agassiz was once regional stuff too  ;)
Title: Re: The 2017 melting season
Post by: be cause on April 30, 2017, 01:34:11 AM
I know it's only a small part of the Arctic involved :) , but North of 80'N temperatures are nearly normal !  It is 2 years since they slipped significantly below normal . The Atlantic warmth that for 6 months was entering the Arctic is turning it's attention elsewhere for the present . The forecasts suggest a return to more general warming in a week . What ever the weather the dmi. 80'N temps are worth watching . The current flat topped mean may not be the shape of things to come ..
Title: Re: The 2017 melting season
Post by: Hyperion on April 30, 2017, 05:45:54 AM
I know it's only a small part of the Arctic involved :) , but North of 80'N temperatures are nearly normal ! 

IMHO that is a sign of the melt process beginning in earnest everywhere the winds approaching the area are coming from. And the porosity of the ice and above normal snow, ice crystals in the air, making for more surface area for the moving air to get at than ever before.
The sublimation and melt and evaporation are sucking the heat out of the air before it gets to the 80+ Nth area?
Title: Re: The 2017 melting season
Post by: Hyperion on April 30, 2017, 05:56:32 AM
Funny thing with your animation Romitt, is that that berg disintergrating did not show on my worldview animations of the same days on the last page. Mysterious. Even more so its still there on the 29th imagery today when I check worldview. Below.

Heres a crack at cheeting the 700px wide rule by turning laptev 21-29 on its side. I am sick of the fiddly biz of selecting and cropping exact frames out of each image to get the best image.

Yep. that worked but you gotta click it. And zoom in with your browzer. (mine anyway)

Some speculation....
even assuming the ice density figures are correct and the free-board estimates calculate the volume are therefore near accurate and Piomass etc are not over-estimating Ice thickness due to that factor. Isn't the extreme youth and lack of deep freeze seasoning with the big FDD anomaly going to mean that a significant fraction of the berg volume is actually brine, and the percentage of crystalline ice lower than usual? Could this mean less ice to melt essentially? And perhaps it would melt at a lower temp than usual, delaying the onset of initial melt advance a little, until suddenly ... FWOOSH! it all goes very quick?

The way the bergs in the laptev animation quickly round off all their corners with a little jostling is suggestive they are very structurally unsound.
Title: Re: The 2017 melting season
Post by: romett1 on April 30, 2017, 10:25:42 AM
Bering Sea and Chukchi Sea have temperatures near zero and above zero for quite a while. In addition to earth.nullschool there is good real-time overview (last 24 - 72 hours) how heat and moisture enter the Arctic from Pacific side.
http://tropic.ssec.wisc.edu/real-time/mtpw2/product.php?color_type=tpw_nrl_colors&prod=alaska&timespan=48hrs&anim=html5 (http://tropic.ssec.wisc.edu/real-time/mtpw2/product.php?color_type=tpw_nrl_colors&prod=alaska&timespan=48hrs&anim=html5)
Title: Re: The 2017 melting season
Post by: Jim Hunt on April 30, 2017, 12:06:02 PM
Funny thing with your animation Romitt, is that that berg disintergrating did not show on my worldview animations of the same days on the last page. Mysterious. Even more so its still there on the 29th imagery today when I check worldview.

If you take a close look at the Terra image for the 28th you can see that two tiles taken at very different times have been pasted together:

https://go.nasa.gov/2ql25sI

Flip to Aqua and the mystery is explained.
Title: Re: The 2017 melting season
Post by: Andreas T on April 30, 2017, 12:10:13 PM
When you talk of "bergs" along the siberian coast, Hyperion, I assume you are thinking of floes of sea ice rather than actual icebergs? It would be better to make the distinction in your use of language. Is that usage a southern hemisphere thing?
I don't think icebergs are present in that part of the arctic since there are no glaciers terminating into the sea. Where those exist they don't produce bergs visible in those satellite images.
The idea of porous ice increasing contact with the air is fanciful (to put it politely) and while first year ice contains more brine than multiyear ice the effects won't be as dramatic as is often speculated here.
Title: Re: The 2017 melting season
Post by: Hyperion on April 30, 2017, 03:28:45 PM
Thanks for pointing out my mistake in the nomenclature Andreas. Not many bergs or floes here in NZ. We may be fresh faced plebs from the colonies here in NZ but I'd hate to be thought as a "berger".
 We did have some giant Bergs visit about ten years ago. Larsen remnants I believe they were believed to be. They actually helicoptered Shrek the rogue merino ram out to be shorn of his ten year 12kg fleece on one as a publicity stunt, would you believe.

Are you sure that the roughness factor is not significant? The constant mobility, pulverisation, slushy mixing in magnitudes more lead area thats been going on all winter suggests to me that a lot of it is barely solid or frozen, loosely bound, waxy rubble, only weeks old. Perhaps more akin to a slushy that's been half-melted, drained, then refrozen. I guess surface area aside, the energy per volume required to melt it is a question.
 I suppose that the question could be answered by getting some sea water, freezing it with some partial thaw, mix and and drain cycles at intervals, and comparing melt energy with a sample prepared by undisturbed deep freeze.

Have plenty of seawater myself but no freezer. Refuse to part with any of the solar electrickeries I net for that. Tri-generation system with wind powered refrigeration pumps and a heavy brine cold store, solar thermal heavy brine hot store, with organic Kalina cycle turbine is on the ship to do list and most of the parts and materials are aboard, but there are other priorities right now.

Thanks Jim.  ;D I assumed it was my use of the Suomi imageset on worldview, not the Gods treating us to a snapshot of a parallel time-stream in the multiverse. ;D
Title: Re: The 2017 melting season
Post by: CognitiveBias on April 30, 2017, 04:02:04 PM
...

The idea of porous ice increasing contact with the air is fanciful (to put it politely) and while first year ice contains more brine than multiyear ice the effects won't be as dramatic as is often speculated here.


http://authors.library.caltech.edu/45129/1/Anderson_1958p632.pdf (http://authors.library.caltech.edu/45129/1/Anderson_1958p632.pdf)

An interesting study including effects of brine and temperature on the strength of sea ice.  While it has been plenty cold, the change in strength of briny (1st year) sea ice seems to extend well into the range of temperatures we have been witnessing.  Deeply frozen multi year ice may well be an order of magnitude stronger than what's out there now. 

 
Title: Re: The 2017 melting season
Post by: Andreas T on April 30, 2017, 06:06:24 PM
Cate has just linked to some great photos taken by a member of NASAs icebridge team from low level flights over the ice in Beaufort.
https://photos.smugmug.com/Field-WorkExpeditions/OIB-Arctic-2017-Daily-Galleries/March-12th-2017-North-Beaufort-Loop/n-NLq4fv/i-L6R4v92/0/3d205ada/XL/i-L6R4v92-XL.jpg (https://photos.smugmug.com/Field-WorkExpeditions/OIB-Arctic-2017-Daily-Galleries/March-12th-2017-North-Beaufort-Loop/n-NLq4fv/i-L6R4v92/0/3d205ada/XL/i-L6R4v92-XL.jpg)
This is the "slush" which occurs when ice breaks and compacts.
Sea ice has always broken and ridged, that thinner and younger ice breaks more easily and in smaller pieces I do not doubt.
The important question is what that means for melting.
Stating the obvious plainly: 1kg of ice requires the same energy input to melt regardless of the shape it is in. The question then becomes: does breaking it into pieces change the transfer of energy to the ice.
If ice is dispersed in a large amount of water warmer than its melting point it will melt faster than a compact lump, it will also cool the water quicker. So it is a question of how much energy is available. Certainly open water absorbs much more sunlight than ice covered water but how much difference is there between 10sq km of ice next to 10sq km of water and 20sq km of smaller floes interspersed with water?
I don't mean to say there are no differences, clearly there may well be differences in convection and salinity around the floes. I just don't expect the dramatic differences some people seem to expect. Last summer there were some spectacular predictions of huge ice loss "a certainty" because of breaks. I have seen nothing to make me think this has a sound basis.
At some point in the future we will see ice so thin it will disperse and melt, how soon that happens is too dependent on many factors to be predictable by eyeballing.
Title: Re: The 2017 melting season
Post by: seaicesailor on April 30, 2017, 07:31:51 PM
Let's try using the long-range weekly CFS-v2 predictions. I bring the 1st and 2nd weeks of May. I will repeat this in the future only if these predictions really make sense (they did for April!)
According to these maps, we should see some more drift in Beaufort sea this first week of May and the next. During the second week, that dome of high pressure mentioned before, pulling heat from America and pushing ice toward the Atlantic.
Temperatures should be anomalously warm in Siberia, then we get the heat fro the American side associated to that high pressure system by the second week. Positive anomalies dominate, certainly in Siberia, certainly not in the Central Arctic.
That the peripheral seas are warm especially the Pacific side does not mean it will be sunny. No cloudiness predictions here. But polynya near the coasts should begin to stay open at both sides.
Note that these forecasts are mean values of different simulations, therefore get diluted with time.
Maps Courtesy of Levi Cowan - tropicaltidbits.com
Title: Re: The 2017 melting season
Post by: Lord M Vader on April 30, 2017, 09:36:45 PM
Dmi shows temps below normal for the first time this year wrt Arctic 80N+
Title: Re: The 2017 melting season
Post by: JayW on May 01, 2017, 12:39:28 AM
First attachment is April 27-30 Suomi VIIRS imagery from the puffin feeder site at the University of Alaska at Fairbanks.
http://feeder.gina.alaska.edu/npp-gina-alaska-truecolor-images?search%5Bfeeds%5D%5B5%5D=1&search%5Bsensors%5D%5B3%5D=1 (http://feeder.gina.alaska.edu/npp-gina-alaska-truecolor-images?search%5Bfeeds%5D%5B5%5D=1&search%5Bsensors%5D%5B3%5D=1)

Second attachment is the NCEP polar drift model 7 day forecast.
http://mag.ncep.noaa.gov/model-guidance-model-parameter.php?group=Model%20Guidance&model=POLAR&area=POLAR&ps=area# (http://mag.ncep.noaa.gov/model-guidance-model-parameter.php?group=Model%20Guidance&model=POLAR&area=POLAR&ps=area#)
Title: Re: The 2017 melting season
Post by: bbr2314 on May 01, 2017, 01:04:35 AM
Looks like we are about to see a pre-cursor to the CAA garlic press commencing in full force. DMI and HYCOM show the thickest ice breaking off of the CAA with potential breakage of the Lincoln Sea ice bridge as well... once this happens it should allow significantly more impact from any cyclones on the ice, and subsequent movement of the CAA ice to the south.
Title: Re: The 2017 melting season
Post by: VeliAlbertKallio on May 01, 2017, 01:15:13 AM
The increase of 3-dimensional surface area of pulverised sea ice versus solid sea ice cover:

1) the thermal inertia of water is transferred  into broken, pulverised ice more easily. This means that the transfer of heat is faster or more efficient when ice passes through water.

2) the long-wave radiation loss from water is reduced when pulverised ice is heavily mixed into water. The water areas stay cooler and loose less heat into space and more goes into melting ice.

3) the vertical mixing of water is stronger with pulverised sea ice than it is with ocean covered with ice film which keeps water beneath ice still and reduces mixing: dipping of ice floes in waves, the ploughing effect of wind pushing ice floes in water, constant rise and dip of water surface due to wave crests and troughs, and air contact with water keeps energy moving around more.

4) the pulverised sea ice surface allows evaporation causing water vapour to form fog, low level clouds that tend to send long wave radiation back to sea surface where it heats and melts ice. Ice film without cloud cover allows heat to escape space provided snow and thickness are not great. With 'ice film' I refer to thin, generally unbroken ice without snow cover on the top.

5) Although the same amount of energy is required to melt solid piece of ice to that of pulverised ice, the accessibility (contact with more water) of heat grows towards infinity the more ice moves and the more ocean mixes vertically, and the faster heat is captured by increasingly pulverised ice.

Cate has just linked to some great photos taken by a member of NASAs icebridge team from low level flights over the ice in Beaufort.
https://photos.smugmug.com/Field-WorkExpeditions/OIB-Arctic-2017-Daily-Galleries/March-12th-2017-North-Beaufort-Loop/n-NLq4fv/i-L6R4v92/0/3d205ada/XL/i-L6R4v92-XL.jpg (https://photos.smugmug.com/Field-WorkExpeditions/OIB-Arctic-2017-Daily-Galleries/March-12th-2017-North-Beaufort-Loop/n-NLq4fv/i-L6R4v92/0/3d205ada/XL/i-L6R4v92-XL.jpg)
This is the "slush" which occurs when ice breaks and compacts.
Sea ice has always broken and ridged, that thinner and younger ice breaks more easily and in smaller pieces I do not doubt.
The important question is what that means for melting.
Stating the obvious plainly: 1kg of ice requires the same energy input to melt regardless of the shape it is in. The question then becomes: does breaking it into pieces change the transfer of energy to the ice.
If ice is dispersed in a large amount of water warmer than its melting point it will melt faster than a compact lump, it will also cool the water quicker. So it is a question of how much energy is available. Certainly open water absorbs much more sunlight than ice covered water but how much difference is there between 10sq km of ice next to 10sq km of water and 20sq km of smaller floes interspersed with water?
I don't mean to say there are no differences, clearly there may well be differences in convection and salinity around the floes. I just don't expect the dramatic differences some people seem to expect. Last summer there were some spectacular predictions of huge ice loss "a certainty" because of breaks. I have seen nothing to make me think this has a sound basis.
At some point in the future we will see ice so thin it will disperse and melt, how soon that happens is too dependent on many factor