Support the Arctic Sea Ice Forum and Blog

Author Topic: The 2015 melting season  (Read 1690612 times)

F.Tnioli

  • Grease ice
  • Posts: 689
    • View Profile
  • Liked: 65
  • Likes Given: 17
Re: The 2015 melting season
« Reply #2100 on: July 14, 2015, 01:37:37 PM »
Yep, bad it is. The pole gets some 24/7 beating lately. Though i'm curious how exactly it's snowing - somewhat - under "H" symbols while in the same time not snowing at all under the "L". In the picture just above. Isn't it strange?

Metamemesis

  • New ice
  • Posts: 38
    • View Profile
  • Liked: 1
  • Likes Given: 1
Re: The 2015 melting season
« Reply #2101 on: July 14, 2015, 01:50:54 PM »
Yep, bad it is. The pole gets some 24/7 beating lately. Though i'm curious how exactly it's snowing - somewhat - under "H" symbols while in the same time not snowing at all under the "L". In the picture just above. Isn't it strange?

That image isn't showing snow; the blue under the High Pressure is just indicating ice without any cloud cover. The only precipitation over the arctic on that map is the tiny splash of green (rain) and the mixed sleet/snow/raid (purple) over the CAB.

F.Tnioli

  • Grease ice
  • Posts: 689
    • View Profile
  • Liked: 65
  • Likes Given: 17
Re: The 2015 melting season
« Reply #2102 on: July 14, 2015, 02:28:42 PM »
Ah, thanks, makes sense. Misleading color legend for "snow" is still there, though. It has some light-blue colors on that "snow" bar in the bottom, see? :) I'd make snow bar shades of yellow in this case, to avoid any possible confusion with bits of surface water / ice. As it is now, it quite looks like, say, whole Mediterranian sea is under heaviest snowfall... Poor Italy's fishermen, must be tough for them!   ;D

No rain/snow under "L", still. Well, happens, i guess. "Milked-out" clouds, eh?

P.S. Also, if to make snow bar being shades of yellow, then heavy snowfall woudn't "mask" blue "L" symbols. Two reasons for a single change. I do not know who precisely makes those particular graphs, though. Please pass the idea to the creator if you can and if you like proposed color change, gentlemen?
« Last Edit: July 14, 2015, 02:44:40 PM by F.Tnioli »

plinius

  • Frazil ice
  • Posts: 403
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: The 2015 melting season
« Reply #2103 on: July 14, 2015, 04:06:13 PM »
At all we know the onset a new Maunder minimum would be barely able to offset the permanent increase in anthropogenic forcing for a decade. That does not even include the fact that even at constant forcing we would continue to warm. So, just forget your hope that the Sun might save the arctic sea ice and even help it to recover. And your PDV or AMV (please do not call those oscillations, they are not, they are long term variabilities) barely offset global temperatures (less than 0.1 K), again less than warming rates caused by us.

Frivolousz21

  • Nilas ice
  • Posts: 1507
  • Live in Belleville, IL..15 miles SE of St. Louis.
    • View Profile
  • Liked: 140
  • Likes Given: 2
Re: The 2015 melting season
« Reply #2104 on: July 14, 2015, 04:20:01 PM »
Is it my impression or are the models slowly moving away from the high pressure-anomalous heat combination? High pressure remains over Greenland, but is much less expansive, starting 4-5 days from now.


 I'd say that is wrong



I got a nickname for all my guns
a Desert Eagle that I call Big Pun
a two shot that I call Tupac
and a dirty pistol that love to crew hop
my TEC 9 Imma call T-Pain
my 3-8 snub Imma call Lil Wayne
machine gun named Missy so loud
it go e-e-e-e-ow e-e-e-e-e-e-blaow

Nightvid Cole

  • Frazil ice
  • Posts: 437
    • View Profile
  • Liked: 5
  • Likes Given: 0
Re: The 2015 melting season
« Reply #2105 on: July 14, 2015, 04:39:46 PM »
Outlined in orange is the "high concentration" region on the NSIDC map (rotated to put Bering Strait on top):



This is very nearly the same as suggested by snow cover one month earlier:


OldLeatherneck

  • Grease ice
  • Posts: 554
    • View Profile
  • Liked: 2
  • Likes Given: 0
Re: The 2015 melting season
« Reply #2106 on: July 14, 2015, 04:48:16 PM »
Is it my impression or are the models slowly moving away from the high pressure-anomalous heat combination? High pressure remains over Greenland, but is much less expansive, starting 4-5 days from now.


 I'd say that is wrong


Friv,

Thanks for bringing  this thread back ON TOPIC!!

While I don't comment or post on this forum as frequently as I did in past years I'm still here on a daily basis.  When I click on this thread, I do it to find out about the 2015 melt season. I want to know what is happening, why it is happening and what is likely to happen in the remaining few months of the melt season.  I value the knowledge and expertise of the vast majority of contributors to this Forum.

Like many others, I have an interest about all of the aspects of Global AGW/CC, both the sciences involved and the potential impacts.  However, I will search for the appropriate topics on other threads.  If i want science fiction, I'll go to the bookstore!

Neven just commented a few entries ago about comments that bleonged elsewhere.  Please folks, let's get back on track.
"Share Your Knowledge.  It's a Way to Achieve Immortality."  ......the Dalai Lama

F.Tnioli

  • Grease ice
  • Posts: 689
    • View Profile
  • Liked: 65
  • Likes Given: 17
Re: The 2015 melting season
« Reply #2107 on: July 14, 2015, 05:07:59 PM »
If i may,i will say one thing about this 'large scale weather modification' idea. it is at the far end of conspiracy theory- in the realm of 'chemtrails' and stuff like that. In ten years we may have natural variation cooling the Arctic( Solar Cycle 25 in hibernation.deeply negative AMO,deeply negative PDO all happening simultaneously). NO point in spraying the atmosphere or whatever with neuro-toxic nano-Aluminium!
Please follow the link to geo-engineering-related topic which i gave earlier on this page, as i can't answer your post here since it won't be anyhow related to 2015 melt season, and re-post there. Otherwise we both risk getting a slap on the back of our heads from moderators, i feel. %)

wili

  • Young ice
  • Posts: 2589
    • View Profile
  • Liked: 163
  • Likes Given: 301
Re: The 2015 melting season
« Reply #2108 on: July 14, 2015, 05:10:51 PM »
What OLn said.

"A force de chercher de bonnes raisons, on en trouve; on les dit; et après on y tient, non pas tant parce qu'elles sont bonnes que pour ne pas se démentir." Choderlos de Laclos "You struggle to come up with some valid reasons, then cling to them, not because they're good, but just to not back down."

seaicesailor

  • Guest
Re: The 2015 melting season
« Reply #2109 on: July 14, 2015, 05:19:08 PM »
Is it my impression or are the models slowly moving away from the high pressure-anomalous heat combination? High pressure remains over Greenland, but is much less expansive, starting 4-5 days from now.


 I'd say that is wrong


Friv,

Thanks for bringing  this thread back ON TOPIC!!

While I don't comment or post on this forum as frequently as I did in past years I'm still here on a daily basis.  When I click on this thread, I do it to find out about the 2015 melt season. I want to know what is happening, why it is happening and what is likely to happen in the remaining few months of the melt season.  I value the knowledge and expertise of the vast majority of contributors to this Forum.

Like many others, I have an interest about all of the aspects of Global AGW/CC, both the sciences involved and the potential impacts.  However, I will search for the appropriate topics on other threads.  If i want science fiction, I'll go to the bookstore!

Neven just commented a few entries ago about comments that bleonged elsewhere.  Please folks, let's get back on track.

Read well past posts, Friv and Neven have not been alone. A few here we trying keep this on track too, it pisses me off as well, but I personally won't engage directly with derailleurs after previous bad experiences, I leave that to mods

jdallen

  • Young ice
  • Posts: 3024
    • View Profile
  • Liked: 189
  • Likes Given: 171
Re: The 2015 melting season
« Reply #2110 on: July 14, 2015, 06:04:54 PM »
In that vein, relocating this post I made from elsewhere.

plinius  Today at 12:59:56 PM
: jdallen  July 13, 2015, 04:49:27 PM
It's optimal melting conditions for sure, combined with some drift; modest surface winds have been shoving the pack from the Northern Laptev towards exits to the Kara and Barents around Franz Josef and to a lesser degree towards the Fram
/end jdallen
Fully agreed, but the main question was why this position is open frequently. Wind pattern/drift certainly plays a role, but after all the fact that it happens downwind from the New Siberian islands, which produce a trough in the ice thickness north of them if the transarctic drift is on, should not be neglected.
/end plinius

Watching patterns in Climate Reanalyzer, I've found it useful to track the flow of moisture.

Pretty persistently, we have a "dry" side - towards Greenland - and a "wet" side, along the Siberian coast.  Now mind, it's not persistent or pervasive, but during the last two weeks of following the changing forecasts and looking at current conditions, I see three major flows of moisture feeding into the Arctic.

The strongest is is from the Pacific side, along the East Asian margin, which breaks against the "RRR" SE of the Gulf of Alaska and then by that gets redirected north - either through the Bering or across the Canadian Rockies and then splitting with part heading east and south and part heading due north into the southern Beaufort.

The second is a flow from SE Asia around the eastern margins of the Himalayas and Gobi, north across Siberia, and dumps into the Eastern Laptev and ESS.

The last is a flow from the eastern Europe that hits the western Kara and merges with Atlantic flow following the gulf stream.

There seem to be two primary outlets of Arctic air displaced - one is across extreme eastern Siberia, which isn't as consistent as the one which runs most typically out across Svalbard-Franz Josef breaking out slantwise down into the Greenland sea.

It seems a reasonably persistent pattern, at weekly scales, and how it seems to be running fits what I'd expect with the heat exchanges and ice melt we've been seeing - Kara getting smashed by flows out of Europe, Bering/Beaufort/Chukchi by flows across out of the Pacific, ice backing up against Svalbard and Franz Josef and somewhat cooler conditions in the CAB.

I'm interested to get others take on it.
This space for Rent.

Neven

  • Administrator
  • First-year ice
  • *****
  • Posts: 7174
    • View Profile
    • Arctic Sea Ice Blog
  • Liked: 713
  • Likes Given: 467
Re: The 2015 melting season
« Reply #2111 on: July 14, 2015, 06:13:16 PM »
Read well past posts, Friv and Neven have not been alone. A few here we trying keep this on track too, it pisses me off as well, but I personally won't engage directly with derailleurs after previous bad experiences, I leave that to mods

I'm going to do better housekeeping in this thread.  :)
Il faut comparer, comparer, comparer, et cultiver notre jardin

Nightvid Cole

  • Frazil ice
  • Posts: 437
    • View Profile
  • Liked: 5
  • Likes Given: 0
Re: The 2015 melting season
« Reply #2112 on: July 14, 2015, 07:39:30 PM »
DMI's thickness map (Danish Polar Portal web site) shows the following for thickness progression over the recent weeks:



I'm a little bit surprised by the thinning being so sensitive to compaction. Though tough to tell from looking at these maps, by paying attention to the yellow region, between June 20th and July 1st, there was considerable thinning, but not so much from July 1st - July 13th, though that region did shrink, due to compaction from the Siberian side (note the edge position). Note that 11 days passed between the first two maps, and 12 days passed between the second and third maps.

If this is accurate, compaction may actually preserve ice, not get rid of it.

seaicesailor

  • Guest
Re: The 2015 melting season
« Reply #2113 on: July 14, 2015, 07:58:34 PM »
DMI's thickness map (Danish Polar Portal web site) shows the following for thickness progression over the recent weeks:


I'm a little bit surprised by the thinning being so sensitive to compaction. Though tough to tell from looking at these maps, by paying attention to the yellow region, between June 20th and July 1st, there was considerable thinning, but not so much from July 1st - July 13th, though that region did shrink, due to compaction from the Siberian side (note the edge position). Note that 11 days passed between the first two maps, and 12 days passed between the second and third maps.

If this is accurate, compaction may actually preserve ice, not get rid of it.

Well, compaction kind of puts the floes together. Actually loss of concentration was brought by cyclone weather

I was expecting greater effect of heat on Chukchi but ...

But compaction is associated with more open water behind the edge, and with warm winds from South too. That could have a "runaway" effect on the retrating edge.


Nick_Naylor

  • Frazil ice
  • Posts: 291
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: The 2015 melting season
« Reply #2114 on: July 14, 2015, 08:03:41 PM »
Visually, the thinning appears to be have slowed dramatically between the first period and the second, but the volume graphic shows just a slight tapering off.

Perhaps that impression is mostly an artifact of the particular color ranges used.

seaicesailor

  • Guest
Re: The 2015 melting season
« Reply #2115 on: July 14, 2015, 08:10:38 PM »


I'm going to do better housekeeping in this thread.  :)

Thank you, Mr Neven by kindly inviting me here, even when I didn't say it before

Edit : I feel invited hehe. Not that anybody actually invited me ;-)

seaicesailor

  • Guest
Re: The 2015 melting season
« Reply #2116 on: July 14, 2015, 08:26:01 PM »
In that vein, relocating this post I made from elsewhere.

plinius  Today at 12:59:56 PM
: jdallen  July 13, 2015, 04:49:27 PM
It's optimal melting conditions for sure, combined with some drift; modest surface winds have been shoving the pack from the Northern Laptev towards exits to the Kara and Barents around Franz Josef and to a lesser degree towards the Fram
/end jdallen
Fully agreed, but the main question was why this position is open frequently. Wind pattern/drift certainly plays a role, but after all the fact that it happens downwind from the New Siberian islands, which produce a trough in the ice thickness north of them if the transarctic drift is on, should not be neglected.
/end plinius

Watching patterns in Climate Reanalyzer, I've found it useful to track the flow of moisture.

Pretty persistently, we have a "dry" side - towards Greenland - and a "wet" side, along the Siberian coast.  Now mind, it's not persistent or pervasive, but during the last two weeks of following the changing forecasts and looking at current conditions, I see three major flows of moisture feeding into the Arctic.

The strongest is is from the Pacific side ...

It seems a reasonably persistent pattern, at weekly scales, and how it seems to be running fits what I'd expect with the heat exchanges and ice melt we've been seeing - Kara getting smashed by flows out of Europe, Bering/Beaufort/Chukchi by flows across out of the Pacific, ice backing up against Svalbard and Franz Josef and somewhat cooler conditions in the CAB.

I'm interested to get others take on it.

It is really bad, look at amazing advances in ESs and Laptev. But Chukchi and Beaufort are having a break.

CAA is going to get badly hit by that first flow you mention from the RRR (nice acronym).

But I am expecting the possibility the blow aligns with Bering and hits the Arctic without America in the middle.
(If that makes any sense).

Laurent

  • Young ice
  • Posts: 2536
    • View Profile
  • Liked: 6
  • Likes Given: 23
Re: The 2015 melting season
« Reply #2117 on: July 14, 2015, 10:08:46 PM »
The ice is wrecked even where it is supposed to be thicker. Notice all the wavy pattern everywhere !
http://rapidfire.sci.gsfc.nasa.gov/imagery/subsets/?subset=Arctic_r03c03.2015195.terra.1km.jpg

Worldview doesn't seem to work today.

Laurent

  • Young ice
  • Posts: 2536
    • View Profile
  • Liked: 6
  • Likes Given: 23
Re: The 2015 melting season
« Reply #2118 on: July 14, 2015, 10:16:32 PM »
And at that pace the North west passage will be open at the end of July. Even the channels toward the north will be open...

jdallen

  • Young ice
  • Posts: 3024
    • View Profile
  • Liked: 189
  • Likes Given: 171
Re: The 2015 melting season
« Reply #2119 on: July 14, 2015, 10:20:56 PM »
And at that pace the North west passage will be open at the end of July. Even the channels toward the north will be open...
Based on how we saw ice acting elsewhere (like the Amundsen Gulf), I'd bet more on the second week of August, possibly the first.
This space for Rent.

OldLeatherneck

  • Grease ice
  • Posts: 554
    • View Profile
  • Liked: 2
  • Likes Given: 0
Re: The 2015 melting season
« Reply #2120 on: July 14, 2015, 10:49:35 PM »
I have 3 questions:

1.  Is it correct that the current SIE in the Hudson and Baffin Bays is ~750K?

2.  Is it a reasonable certainty that both Hudson and Baffin will melt out completely in 2015? If so, when?

3.  For the next few weeks, what regions of the Arctic are most vulnerable to significant losses?
"Share Your Knowledge.  It's a Way to Achieve Immortality."  ......the Dalai Lama

ChrisReynolds

  • Nilas ice
  • Posts: 1714
    • View Profile
    • Dosbat
  • Liked: 1
  • Likes Given: 0
Re: The 2015 melting season
« Reply #2121 on: July 14, 2015, 11:10:38 PM »
I have 3 questions:

1.  Is it correct that the current SIE in the Hudson and Baffin Bays is ~750K?

2.  Is it a reasonable certainty that both Hudson and Baffin will melt out completely in 2015? If so, when?

3.  For the next few weeks, what regions of the Arctic are most vulnerable to significant losses?

I've only just got round to downloading and reviewing data from the last few days, been busy.

1. Don't know, haven't had the chance to check.

2. Haven't they generally melted out in recent years? I think they will melt out.

3. Watch Chukchi, ESS, Laptev, what's happening there is very exciting.

***

While watching a slideshow of Bremen for the last few years I was reminded of "2010: The Year We Make Contact". Where Jupiter darkens and shrinks....

Anyone see any dark rectangles on Modis?  ;)


OldLeatherneck

  • Grease ice
  • Posts: 554
    • View Profile
  • Liked: 2
  • Likes Given: 0
Re: The 2015 melting season
« Reply #2122 on: July 14, 2015, 11:16:51 PM »
I have 3 questions:

1.  Is it correct that the current SIE in the Hudson and Baffin Bays is ~750K?

2.  Is it a reasonable certainty that both Hudson and Baffin will melt out completely in 2015? If so, when?

3.  For the next few weeks, what regions of the Arctic are most vulnerable to significant losses?

I've only just got round to downloading and reviewing data from the last few days, been busy.

1. Don't know, haven't had the chance to check.

2. Haven't they generally melted out in recent years? I think they will melt out.

3. Watch Chukchi, ESS, Laptev, what's happening there is very exciting.

***

While watching a slideshow of Bremen for the last few years I was reminded of "2010: The Year We Make Contact". Where Jupiter darkens and shrinks....

Anyone see any dark rectangles on Modis?  ;)

Thanks Chris!!
"Share Your Knowledge.  It's a Way to Achieve Immortality."  ......the Dalai Lama

plinius

  • Frazil ice
  • Posts: 403
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: The 2015 melting season
« Reply #2123 on: July 14, 2015, 11:36:03 PM »
If this is accurate, compaction may actually preserve ice, not get rid of it.

If I may note that if you look at "average thickness", this is the average thickness of the ice covered area times the concentration. Example: You compact 2m thick floes with 70% coverage to 1.6m thick floes (quite a melt...) with 90% coverage. Average thickness rises from 1.40m to 1.44m.
The ice has been converging on your region, so at that place it looks like it has been good weather. In truth, however, you lost 20% of your ice volume.
Happening here too: Compare these two animations next to each other:
http://www7320.nrlssc.navy.mil/hycomARC/navo/arcticictn_nowcast_anim30d.gif
http://www7320.nrlssc.navy.mil/hycomARC/navo/arcticicen_nowcast_anim30d.gif

slow wing

  • Grease ice
  • Posts: 792
    • View Profile
  • Liked: 145
  • Likes Given: 399
Re: The 2015 melting season
« Reply #2124 on: July 15, 2015, 12:56:16 AM »
DMI's thickness map (Danish Polar Portal web site) shows the following for thickness progression over the recent weeks:



I'm a little bit surprised by the thinning being so sensitive to compaction. Though tough to tell from looking at these maps, by paying attention to the yellow region, between June 20th and July 1st, there was considerable thinning, but not so much from July 1st - July 13th, though that region did shrink, due to compaction from the Siberian side (note the edge position). Note that 11 days passed between the first two maps, and 12 days passed between the second and third maps.

If this is accurate, compaction may actually preserve ice, not get rid of it.
I'm suspicious of the progression shown by the 3 plots.

In particular, look at the region around 150 degrees West (11 o'clock) and just inside the 80 degrees North latitude circle. It shows reddish in the earliest plot, then greeny-yellow, then back to yellow.

So the sequence shown there is that a whole region of ice started at around 4 m thick, then dropped below 3m in only 11 days(!) followed by bouncing back over 12 days to around 3.5m.

The region is too large for that to be transport in and out of the region, and that anyway doesn't jibe with the nearby ice features.

That looks unphysical to me.

I'm guessing they have been tuning their parameters over the time interval covered by the plots, so the three plots don't show a consistent time evolution and shouldn't really be trusted for that purpose.



 

DavidR

  • Grease ice
  • Posts: 731
    • View Profile
  • Liked: 30
  • Likes Given: 3
Re: The 2015 melting season
« Reply #2125 on: July 15, 2015, 01:04:26 AM »

I have 3 questions:

1.  Is it correct that the current SIE in the Hudson and Baffin Bays is ~750K?

2.  Is it a reasonable certainty that both Hudson and Baffin will melt out completely in 2015? If so, when?

3.  For the next few weeks, what regions of the Arctic are most vulnerable to significant losses?

If you  check out this graphic from Wipneus you  can see that Sea Ice Area in Hudson and Baffin Bays is approximately 500K Km^2 higher than recent  years which would make the extent  difference about 750 K at the current  average measure of compaction (67% for NSIDC data).

https://sites.google.com/site/arctischepinguin/home/amsr2/grf/amsr2-area-regional.png

Even 40 years ago the ice in Hudson Bay was typically all gone by Mid August  http://pubs.aina.ucalgary.ca/arctic/Arctic24-2-90.pdf
and according to this information from NSIDC nothing has changed
http://nsidc.org/data/smmr_ssmi_ancillary/regions/hudson.html

and for Baffin there is rarely much ice left at the minimum.
http://nsidc.org/data/smmr_ssmi_ancillary/regions/baffin.html
« Last Edit: July 15, 2015, 03:02:43 AM by DavidR »
Toto, I've a feeling we're not in Kansas anymore

slow wing

  • Grease ice
  • Posts: 792
    • View Profile
  • Liked: 145
  • Likes Given: 399
Re: The 2015 melting season
« Reply #2126 on: July 15, 2015, 04:11:16 AM »
Another daily update to University of Bremen AMSR2 ice concentration map...

Lots of action on the Siberian side - both gains and losses.

And the thick multi-year ice in the Beaufort Sea continues to heal up to higher concentrations - presumably due to melt ponds refreezing. But a few moth-holes are getting larger, right in amongst the high concentration ice!

Will the moths eat the Beaufort ice?


Click on the .gif to animate a comparison to yesterday.



plinius

  • Frazil ice
  • Posts: 403
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: The 2015 melting season
« Reply #2127 on: July 15, 2015, 04:20:39 AM »
And the thick multi-year ice in the Beaufort Sea continues to heal up to higher concentrations - presumably due to melt ponds refreezing. But a few moth-holes are getting larger, right in amongst the high concentration ice!

In those conditions I would seriously doubt any melt ponds to refreeze. What you are seeing is to a large part surface convergence


that's approximately as much convergence as you can get... in particular with thick ice being pushed towards the Beaufort from north of Greenland.

slow wing

  • Grease ice
  • Posts: 792
    • View Profile
  • Liked: 145
  • Likes Given: 399
Re: The 2015 melting season
« Reply #2128 on: July 15, 2015, 05:21:10 AM »
In those conditions I would seriously doubt any melt ponds to refreeze. What you are seeing is to a large part surface convergence
Maybe you're right. But I struggle to see how the numbers work out for that.

It looks like an area in the Beaufort Sea of order (~) ~1 million km^2 (draw a boundary line enclosing one) has gained some percentage points of average concentration over only 1 day.

So it has added some tens of thousands of km^2 ice area.

You're suggesting that ice has all flowed in from outside the area, crossing the boundary line.

But the boundary line is only some thousands of km long.

And your flow map is showing flows ~10 cm/s ~10 km/day in the Beaufort region.

If it was pure inward flow perpendicular to the boundary everywhere then it could add
~ 10 km/day x ~few 1000 km ~few 10,000's km^2/day, and adding some tens of thousands of km^2 ice area would be realistic.

But wind & ice flows are typically not like that. Their 2-dimensional divergences are typically fairly small.


Admittedly, your map does show such a negative divergence in the Beaufort for today. It looks too small but I wouldn't swear to that. So at the moment I am agnostic on this...

An alternative explanation would be some sort of day-night effect in when the satellite data is taken. Obviously, night would generally be colder and give the ice a chance to freeze. Are the satellite orbits such that that might fly as an explanation?



I am just an interested amateur, so what do I know? How confident are you it is indeed due to divergences? If you're an expert and confident then I might accept it...  :P




« Last Edit: July 15, 2015, 05:26:11 AM by slow wing »

seaicesailor

  • Guest
Re: The 2015 melting season
« Reply #2129 on: July 15, 2015, 05:22:27 AM »
Another daily update to University of Bremen AMSR2 ice concentration map...

Lots of action on the Siberian side - both gains and losses.

And the thick multi-year ice in the Beaufort Sea continues to heal up to higher concentrations - presumably due to melt ponds refreezing. But a few moth-holes are getting larger, right in amongst the high concentration ice!

Will the moths eat the Beaufort ice?


Click on the .gif to animate a comparison to yesterday.

FWIW there is a bouy that is outputting rather exceptional data around the location of that biggest hole, see the buoy thread

https://forum.arctic-sea-ice.net/index.php/topic,327.msg56611.html#msg56611

And there was this buoy 2014F that showed freak bottom melt in the middle of the Beaufort but it is W145°, many miles away from this hole.
« Last Edit: July 15, 2015, 05:28:27 AM by seaicesailor »

seaicesailor

  • Guest
Re: The 2015 melting season
« Reply #2130 on: July 15, 2015, 05:33:33 AM »
In those conditions I would seriously doubt any melt ponds to refreeze. What you are seeing is to a large part surface convergence
Maybe you're right. But I struggle to see how the numbers work out for that.

 

The area was pretty cloudy yesterday. That also affects AMSR2 concentration measurements (upwards, or so I am told)

slow wing

  • Grease ice
  • Posts: 792
    • View Profile
  • Liked: 145
  • Likes Given: 399
Re: The 2015 melting season
« Reply #2131 on: July 15, 2015, 05:40:35 AM »
Interesting on the buoy data near the moth hole! Thanks, SeaIceSailor.

I also have a related question for the buoy experts (e.g. Jim Hunt).

With so much of the thick ice positioned in front of the Bering Strait this year, how good is the data on heat inflow from water through the Strait?

Do we have a good idea, or not, on whether this year will be better or worse than average? (Recall 2007, where the influx was exceptional - about twice normal if I recall correctly - and it really dented the ice on the Pacific side.)

Bruce Steele

  • Nilas ice
  • Posts: 1458
    • View Profile
  • Liked: 127
  • Likes Given: 10
Re: The 2015 melting season
« Reply #2132 on: July 15, 2015, 06:42:12 AM »
ITP 87 is at 75.5312 N. 135.0589 W.  The moth-hole offshore Mc Clure Strait looks to be closest to the 87 profiler. Eddies?

Lord M Vader

  • Nilas ice
  • Posts: 1263
    • View Profile
  • Liked: 26
  • Likes Given: 19
Re: The 2015 melting season
« Reply #2133 on: July 15, 2015, 09:19:31 AM »
ECMWF 00z run depicts a very interesting dipole set up in the end of the forecast time. Let's see if this forecast idea holds for the next couple of runs... Continues to be a blow torch on the ice. In worst case scenairo, 2015 is muscling up things for 2016 which could be really worrysome if a La Niña comes in charge by the summer of 2016...

In the Beaufort Sea, several polynyas are growing in the MYI pack.

I think there are good chances for a long, smooth and late minima this year as the fringe areas will offset the refreezing areas in September.

By July 25 the northern Sea route should be more or less "ice free".

//LMV

F.Tnioli

  • Grease ice
  • Posts: 689
    • View Profile
  • Liked: 65
  • Likes Given: 17
Re: The 2015 melting season
« Reply #2134 on: July 15, 2015, 10:14:12 AM »
DMI's thickness map (Danish Polar Portal web site) shows the following for thickness progression over the recent weeks:



I'm a little bit surprised by the thinning being so sensitive to compaction. Though tough to tell from looking at these maps, by paying attention to the yellow region, between June 20th and July 1st, there was considerable thinning, but not so much from July 1st - July 13th, though that region did shrink, due to compaction from the Siberian side (note the edge position). Note that 11 days passed between the first two maps, and 12 days passed between the second and third maps.

If this is accurate, compaction may actually preserve ice, not get rid of it.
I'm suspicious of the progression shown by the 3 plots.

In particular, look at the region around 150 degrees West (11 o'clock) and just inside the 80 degrees North latitude circle. It shows reddish in the earliest plot, then greeny-yellow, then back to yellow.

So the sequence shown there is that a whole region of ice started at around 4 m thick, then dropped below 3m in only 11 days(!) followed by bouncing back over 12 days to around 3.5m.

The region is too large for that to be transport in and out of the region, and that anyway doesn't jibe with the nearby ice features.

That looks unphysical to me.

I'm guessing they have been tuning their parameters over the time interval covered by the plots, so the three plots don't show a consistent time evolution and shouldn't really be trusted for that purpose.
Good eye. I agree it shouldn't be transport.

But not so sure about parameters. My guess is that inputs are much responsible. Perhaps melt ponds could probably be counted, up to some point, as a part of ice's thickness? If so, then later on with most ponds finding their drainage into the ocean, that ~3m thick ice bouyancy would kick in - the weight of melt ponds before the drainage into the ocean would be removed, and the ice would rise up as a result. Up to ~8% of 3m, i.e. by up to 24 centimeters, which is quite much. And this is quite physical.

There are possibly other uncertainties and errors involved, possibly including changes in humidity, remnants of snow cover, salinity and who knows what else. If my memory serves, i've seen such short-term relatively local "flashbacks" of thickness during previous years in thickness animated graphs, source being other than DMI. Sadly, i don't remember where exactly i was noticing that, it's been quite some time.

And i really doubt researchers in DMI would tweak their parameters mid-season, even if rather large errors would be found: they do understand, just like we do, that it's better to let parameter errors be until the melt is definitely complete, to get the melt season's dynamics in their data unaffected by any large parameters' change.

edit: something REALLY strange with this one, though. I narrowed the thing to two days: June 29th and June 30th. Both days see a HUGE drop in said area, up to 1m in two days! Did we have any special weather anomaly in said region (~150 degrees West, some 80...82 North) during June 28th...30th, which could possibly affect inputs?
« Last Edit: July 15, 2015, 10:53:58 AM by F.Tnioli »

Shared Humanity

  • Young ice
  • Posts: 3960
    • View Profile
  • Liked: 416
  • Likes Given: 48
Re: The 2015 melting season
« Reply #2135 on: July 15, 2015, 02:36:53 PM »
Is it my impression or are the models slowly moving away from the high pressure-anomalous heat combination? High pressure remains over Greenland, but is much less expansive, starting 4-5 days from now.


 I'd say that is wrong


Friv,

Thanks for bringing  this thread back ON TOPIC!!

While I don't comment or post on this forum as frequently as I did in past years I'm still here on a daily basis.  When I click on this thread, I do it to find out about the 2015 melt season. I want to know what is happening, why it is happening and what is likely to happen in the remaining few months of the melt season.  I value the knowledge and expertise of the vast majority of contributors to this Forum.

Like many others, I have an interest about all of the aspects of Global AGW/CC, both the sciences involved and the potential impacts.  However, I will search for the appropriate topics on other threads.  If i want science fiction, I'll go to the bookstore!

Neven just commented a few entries ago about comments that bleonged elsewhere.  Please folks, let's get back on track.

Thanks for saying this so I don't have to.

Shared Humanity

  • Young ice
  • Posts: 3960
    • View Profile
  • Liked: 416
  • Likes Given: 48
Re: The 2015 melting season
« Reply #2136 on: July 15, 2015, 02:51:51 PM »
Sure looks like the MYI is holding up very well in the Beaufort. 2 to 2.5 meters thick across most of the area.

seaicesailor

  • Guest
Re: The 2015 melting season
« Reply #2137 on: July 15, 2015, 03:09:51 PM »
Sure looks like the MYI is holding up very well in the Beaufort. 2 to 2.5 meters thick across most of the area.

2014 I reports 134 cm thickness
2015 B reports 171 cm thickness
2013 B reports 225 cm
2015 A and 2014 F are floating around

PIOMAS estimated an effective thickness ~1 m or so in Beaufort

I conclude ice thicker than 2 m is highly improbable and thinner than 1 m is highly probable by now


Shared Humanity

  • Young ice
  • Posts: 3960
    • View Profile
  • Liked: 416
  • Likes Given: 48
Re: The 2015 melting season
« Reply #2138 on: July 15, 2015, 03:45:03 PM »
Sure looks like the MYI is holding up very well in the Beaufort. 2 to 2.5 meters thick across most of the area.

2014 I reports 134 cm thickness
2015 B reports 171 cm thickness
2013 B reports 225 cm
2015 A and 2014 F are floating around

PIOMAS estimated an effective thickness ~1 m or so in Beaufort

I conclude ice thicker than 2 m is highly improbable and thinner than 1 m is highly probable by now

I may be looking at it wrong but does this mean the DMI images posted above are not correct?

seaicesailor

  • Guest
Re: The 2015 melting season
« Reply #2139 on: July 15, 2015, 03:57:14 PM »
Sure looks like the MYI is holding up very well in the Beaufort. 2 to 2.5 meters thick across most of the area.

2014 I reports 134 cm thickness
2015 B reports 171 cm thickness
2013 B reports 225 cm
2015 A and 2014 F are floating around

PIOMAS estimated an effective thickness ~1 m or so in Beaufort

I conclude ice thicker than 2 m is highly improbable and thinner than 1 m is highly probable by now

I may be looking at it wrong but does this mean the DMI images posted above are not correct?

I cannot say what is right and what is wrong but PIOMAS looked to me credible at least for Beaufort given the amount of open water and the (so few) buoy data.


iceman

  • Frazil ice
  • Posts: 285
    • View Profile
  • Liked: 7
  • Likes Given: 19
Re: The 2015 melting season
« Reply #2140 on: July 15, 2015, 04:52:58 PM »
The "Laptev Lobe" in the southern part of the sea is only a week or two away from getting cut off from the main pack.  iirc that will be the largest ice detachment since the 2012 cyclone.

seaicesailor

  • Guest
Re: The 2015 melting season
« Reply #2141 on: July 15, 2015, 07:35:21 PM »

Just for fun. The crazy weather forecast for Barrow AK by weatherBug
Most Bizarre
8)


plinius

  • Frazil ice
  • Posts: 403
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: The 2015 melting season
« Reply #2142 on: July 15, 2015, 07:47:33 PM »
Looks like utter nonsense. Forecast from a serious site:
http://www.wunderground.com/cgi-bin/findweather/hdfForecast?query=Barrow%2C+AK

Tor Bejnar

  • Young ice
  • Posts: 3042
    • View Profile
  • Liked: 362
  • Likes Given: 188
Re: The 2015 melting season
« Reply #2143 on: July 15, 2015, 10:11:39 PM »
According to DMI, the latest 'north of 80' temperature is higher than at any time in 2012.  2015's early melt season started cool, but has fairly well kept up with 2012.  2012, of course, had a late 'lets keep sort of warm' period that must have helped.
Arctic ice is healthy for children and other living things.

Buddy

  • Young ice
  • Posts: 3325
  • Go DUCKS!!
    • View Profile
  • Liked: 40
  • Likes Given: 31
Re: The 2015 melting season
« Reply #2144 on: July 16, 2015, 02:21:28 AM »
The "game" between 2015 and 2012 is DEFINITELY not over yet.  Ice is looking crappy....and the heat is on.

FOX (RT) News....."The Trump Channel.....where truth and journalism are dead."

Blizzard_of_Oz

  • New ice
  • Posts: 21
    • View Profile
    • 50-Day melt season forecast
  • Liked: 0
  • Likes Given: 0
Re: The 2015 melting season
« Reply #2145 on: July 16, 2015, 03:29:47 AM »
According to DMI, the latest 'north of 80' temperature is higher than at any time in 2012.  2015's early melt season started cool, but has fairly well kept up with 2012.  2012, of course, had a late 'lets keep sort of warm' period that must have helped.

Alternative comparison ... (not that air temperature tells the whole story)



http://cires1.colorado.edu/~aslater/ARCTIC_TAIR/

slow wing

  • Grease ice
  • Posts: 792
    • View Profile
  • Liked: 145
  • Likes Given: 399
Re: The 2015 melting season
« Reply #2146 on: July 16, 2015, 03:55:06 AM »
The lower-concentration ice is back in the Beaufort. So which, out of the possibilities we discussed, changed back since yesterday?


Andreas T

  • Nilas ice
  • Posts: 1126
    • View Profile
  • Liked: 11
  • Likes Given: 2
Re: The 2015 melting season
« Reply #2147 on: July 16, 2015, 08:59:21 AM »
The satellite sensor the sea ice concentration chart is based on is detecting surface water. Camera2 which was colocated with IMB2015B but now has no GPS location I know of, shows the image below.  At other times it showed open water. What does the sensor see? By the nature of the passive microwave sensor it has low reolution. Trying to interpret every reduction in ice concentration seen by the sensor as melting is misunderstanding what it shows. Converging and diverging movement, breaking and dispersing floes, wetting of surfaces by rain has effects which can not easily assessed by "eyeballing".

Andreas T

  • Nilas ice
  • Posts: 1126
    • View Profile
  • Liked: 11
  • Likes Given: 2
Re: The 2015 melting season
« Reply #2148 on: July 16, 2015, 09:29:55 AM »
According to DMI, the latest 'north of 80' temperature is higher than at any time in 2012.  2015's early melt season started cool, but has fairly well kept up with 2012.  2012, of course, had a late 'lets keep sort of warm' period that must have helped.

The timing of the late warmth in 2012 suggests to me that the large open water area kept air warm when temperatures over ice would have fallen rapidly in other years. How fast that warmth leaves the atmosphere(at the top) at the same time is what I would like to know because it helps to answer whether low ice means stronger volume growth.

Frivolousz21

  • Nilas ice
  • Posts: 1507
  • Live in Belleville, IL..15 miles SE of St. Louis.
    • View Profile
  • Liked: 140
  • Likes Given: 2
Re: The 2015 melting season
« Reply #2149 on: July 16, 2015, 12:48:34 PM »
Those dmi thickness graphics are trash.

The 00z models are EPIC.

The Hudson and Baffin still holding things up.
Laptev will melt out completely.

The bottom is gonna drop out soon.


I got a nickname for all my guns
a Desert Eagle that I call Big Pun
a two shot that I call Tupac
and a dirty pistol that love to crew hop
my TEC 9 Imma call T-Pain
my 3-8 snub Imma call Lil Wayne
machine gun named Missy so loud
it go e-e-e-e-ow e-e-e-e-e-e-blaow