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F.Tnioli

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Re: The 2017 melting season
« Reply #2150 on: June 20, 2017, 05:14:44 PM »
I've seen a lot of snow melt, some deep and some shallow.  I recall thin snow (sometimes on lake ice) develop something like melt ponds.  I also recall walking in the spring through foot-deep snow and coming to 'bogs' where the surface was grey and 'melt pondy' or even a temporary pond, and places where the surface was pristine white but my feet got soaked by the hidden water below.

I want to guess there is a lot of this hidden water below the surface sort of melt pond in the Arctic right now.  The white surface is certainly causing a great deal of reflectance, but real damage is happening below, none-the-less.
F. Tnioli, here is the comment. I got snapped at earlier for referring back to it myself, but it makes sense to me. A percentage of energy gets past the snow surface, and some ponding could have formed between snows.
But that happens over soil frequently. However to find lhat pool of water sandwiched between snow and -1.8C or so of ice, which is under freezing temp for hypothetically melting snow or fresh-water, and without the direct source of heat ( siince insulated both at the top and bottom). I don't see it...
Yes, i meant exactly this, thank you, gentlemen. About insulation from both top and bottom - bottom part is more questionable this season than ever, in general, with thinner ice and cracks everywhere, so if salinity makes its way (some wave action) on top of some ice, that's -1.8C "melt" pond alright, and snow on top is pretty much fresh water which won't melt until ~0C, so that's one thing. Another is, of course, the Sun. It's quite more complex than just "it's either sunny or not there and then", tbh; some thin clouds allow fair share of that peak insolation to filter down and when it's 24/7 at some places, i bet it takes its toll.

Still, perhaps i'm wrong about it, yes; quite possibly such effects are too weak to be any serious contributor to the compactness (reported / graphed) as we see it.

FishOutofWater

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Re: The 2017 melting season
« Reply #2151 on: June 20, 2017, 05:42:28 PM »
Storms in June do bring a cooler, cloudier central Arctic and help preserve sea ice but be careful with the 850mb temperatures. There's a very different atmospheric sounding under an upper level low than under an upper level high. There's subsidence, and often an inversion under the high.

I'm not surprised at all by the warm air coming into the Arctic from the continents when there's a low over the ocean. This situation will see damage to the ice over the CAA and the ESS.

Tigertown

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Re: The 2017 melting season
« Reply #2152 on: June 20, 2017, 10:25:11 PM »
NSIDC SIE     x 106 km2

2017,    06,  12,     11.069
2017,    06,  13,     10.959
2017,    06,  14,     10.869
2017,    06,  15,     10.788
2017,    06,  16,     10.677

That's about -98,000 km2 a day for the last 4 days reported.


UPDATE
2017,    06,  17,     10.605
2017,    06,  18,     10.537
2017,    06,  19,     10.453

Thawing Thunder

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Re: The 2017 melting season
« Reply #2153 on: June 21, 2017, 12:35:16 AM »
Rough guess: Now the average is down to 89.000 km2. Not that "bad". Or rather: Bad enough.
The Thunder was father of the first people, and the Moon was the first mother. But Maxa'xâk, the evil horned serpent, destroyed the Water Keeper Spirit and loosed the waters upon the Earth and the first people were no more.

Tigertown

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Re: The 2017 melting season
« Reply #2154 on: June 21, 2017, 01:16:32 AM »
I don't expect much of a SIE drop for JAXA, but looking at the big picture, things are going down quality wise. 17th-19th. The illusory thick ice is all but gone now.

JayW

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Re: The 2017 melting season
« Reply #2155 on: June 21, 2017, 01:27:08 AM »
I don't expect much of a SIE drop for JAXA, but looking at the big picture, things are going down quality wise. 17th-19th. The illusory thick ice is all but gone now.

Threre is also the ascending pass which always looks a little different.

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Tigertown

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Re: The 2017 melting season
« Reply #2156 on: June 21, 2017, 01:29:58 AM »
Thanks JayW. I didn't know that, and you are certainly right. The details seem more accurate.

slow wing

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Re: The 2017 melting season
« Reply #2157 on: June 21, 2017, 02:45:45 AM »
  19 June is one of the dates displayed in Neven's excellent year-to-year comparison of U. Bremen's AMSR2 sea ice concentration maps: https://sites.google.com/site/arcticseaicegraphs/concentration-maps/sic0619.

  I mainly look at the ice pack in the Arctic Basin as that is what mainly determines what sea ice is left at the end of the melt season.

  This year's Arctic Basin at 19 June shows the melt at the pack edge is advanced this year inside the Bering Strait and relatively advanced in the Beaufort Sea and on the Russian side.

   However, the pack itself looks generally darker than in previous years.

   What should be pointed out as at least a partial explanation is that THE COLOUR PALETTE CHANGED THIS YEAR.

There is no longer a light concentration band near 100% that can produce light flecks all over the ice pack.

Shown below is the 19 June map comparison as well as the colour palettes for 2016 and 2017 with the change circled.



Archimid

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Re: The 2017 melting season
« Reply #2158 on: June 21, 2017, 04:24:33 AM »
This animation is from the Beaufort Sea. That looks like a poof to me.(Needs a click)
« Last Edit: June 21, 2017, 04:37:45 AM by Archimid »
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Tor Bejnar

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Re: The 2017 melting season
« Reply #2159 on: June 21, 2017, 05:18:39 AM »
"Poof" indeed!  Quite telling is the large floe that shows up on the 19th from the bottom (actually, its tip shows up on the 17), all angular and he-man looking, and on the 20th it looks like a beaten old man, with brash ice streaming off of it.

It actually quite surprises me how intensely the disintegration progresses.
Arctic ice is healthy for children and other living things.

Tigertown

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Re: The 2017 melting season
« Reply #2160 on: June 21, 2017, 05:21:33 AM »
@Archimid
The SST's just offshore of the Mackenzie Delta are over 3oC and the surface air is over 5oC. You can see the muddy river water making it's way out to the sea ice. Both the air and water temps. are probably diminished by that point, but evidently carry enough heat energy to do some damage, with the help of uncle insolation.

P.S. I seem to remember reading that it doesn't take running river water long to warm after the land around it begins to do so, which it has in this area.
« Last Edit: June 21, 2017, 05:30:15 AM by Tigertown »

John Batteen

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Re: The 2017 melting season
« Reply #2161 on: June 21, 2017, 06:35:24 AM »
One thing I ponder as I watch this season's melt is the affect of ice chunk size and surface area exposed to water. There is already enough energy in the Arctic to melt the ice, just no easy way to transfer it to the ice. But as the ice disintegrates and gains surface area, it will be easier and easier for a good windy storm to stir the ice and melt it.

epiphyte

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Re: The 2017 melting season
« Reply #2162 on: June 21, 2017, 08:05:21 AM »
"Poof" indeed!  Quite telling is the large floe that shows up on the 19th from the bottom (actually, its tip shows up on the 17), all angular and he-man looking, and on the 20th it looks like a beaten old man, with brash ice streaming off of it.

It actually quite surprises me how intensely the disintegration progresses.

Quite. If you look hard, you can see it almost everywhere. The CAB and surroundings are shrouded in cloud, but wherever there's a gap, there's evidence of ongoing collapse. To repeat. again. This is not a slow season.

JayW

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Re: The 2017 melting season
« Reply #2163 on: June 21, 2017, 09:47:21 AM »
First attachment is June 14-20, of the Beaufort.

Second attachment is the ECMWF forecast for the next week.  After a prolonged period of easterly winds, they are progged to swing around from the west for a week or so.  With the Beaufort gyre not looking that prominent, it may slow even further, and I wodidn't be surprised to see Beaufort extent tick up as sea ice is blown into the open water.

Suomi VIIRS imagery from the puffin feeder site at the University of Alaska
http://feeder.gina.alaska.edu/npp-gina-alaska-truecolor-images?page=4&search%5Bfeeds%5D%5B5%5D=1&search%5Bsensors%5D%5B3%5D=1

ECMWF images courtesy of Levi Cowan and tropical tidbits
http://www.tropicaltidbits.com/analysis/models/?model=ecmwf&region=ak&pkg=T850&runtime=2017062100&fh=0&xpos=0&ypos=38
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Crocodile23

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Re: The 2017 melting season
« Reply #2164 on: June 21, 2017, 10:42:57 AM »
 Compared to last year, the state of the distribution of sea ice(for June 20 of 2017 and 2016 i put on animated GIF below) is completely different in my eyes. But can you experienced people explain what distribution favours more the ice melt? This year or last year and why? In order we beginner's on all these to learn.



Tigertown

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Re: The 2017 melting season
« Reply #2165 on: June 21, 2017, 12:20:18 PM »
Compared to last year, the state of the distribution of sea ice(for June 20 of 2017 and 2016 i put on animated GIF below) is completely different in my eyes. But can you experienced people explain what distribution favours more the ice melt? This year or last year and why? In order we beginner's on all these to learn.
The distribution can change very easily, because of how busted up the ice is. It is not very thick, either. I would not count it to fare well, but rather just hope some up of it is left at the end.
« Last Edit: June 21, 2017, 12:27:26 PM by Tigertown »

Shared Humanity

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Re: The 2017 melting season
« Reply #2166 on: June 21, 2017, 01:03:37 PM »
Compared to last year, the state of the distribution of sea ice(for June 20 of 2017 and 2016 i put on animated GIF below) is completely different in my eyes. But can you experienced people explain what distribution favours more the ice melt? This year or last year and why? In order we beginner's on all these to learn.

The extra ice in the Kara, Barents and Greenland Seas this year is not good. It should all be gone by the end of the melt season IMHO.

Thawing Thunder

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Re: The 2017 melting season
« Reply #2167 on: June 21, 2017, 02:27:05 PM »
In fact the core area looks much worse. All the southern ice will be gone in a couple of weeks and the "garlic press" started much earlier in 2017.

It could become even worse: When the easy ice - for example in Hudson Bay - is gone, the melt in some years stalled for a while. This year, with so much ice left in the southern areas for the hot weeks after solstice, the lines of the graphs will probably go straight downwards.
« Last Edit: June 21, 2017, 02:37:29 PM by Thawing Thunder »
The Thunder was father of the first people, and the Moon was the first mother. But Maxa'xâk, the evil horned serpent, destroyed the Water Keeper Spirit and loosed the waters upon the Earth and the first people were no more.

Jim Hunt

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Re: The 2017 melting season
« Reply #2168 on: June 21, 2017, 02:44:07 PM »
The "garlic press" started much earlier in 2017.

How do you come to that conclusion? My understanding is that the term "garlic press" refers to multi-year ice moving from the Central Arctic through the Canadian Arctic Archipelago. Your understanding would seem to be different from mine?
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Neven

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Re: The 2017 melting season
« Reply #2169 on: June 21, 2017, 03:02:56 PM »
He may be referring to the Nares pasta machine.

Compared to last year, the state of the distribution of sea ice(for June 20 of 2017 and 2016 i put on animated GIF below) is completely different in my eyes. But can you experienced people explain what distribution favours more the ice melt? This year or last year and why? In order we beginner's on all these to learn.

The large expanses of open water in the Chukchi, ESS and Laptev definitely constitute a difference with last year. Beaufort might be slightly worse last year. Retreat was more advanced on the Atlantic side last year, but that means there's more export this year.

In principle this year's distribution would favour more ice melt, when compared to last year, but of course weather, melt ponding and ocean heat flux, blah blah blah.
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romett1

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Re: The 2017 melting season
« Reply #2170 on: June 21, 2017, 03:15:35 PM »
About this cyclone - thickness levels are going to be interesting near North Pole. Compared Jun 19 actual vs Jun 27 forecast. Images: https://www7320.nrlssc.navy.mil/hycomARC/arctic.html

iceman

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Re: The 2017 melting season
« Reply #2171 on: June 21, 2017, 03:35:40 PM »
Neven, thanks for Reply #2121 and its links, informing that in 2013 the Arctic Basin also had a strong and persistent low pressure system in June.

That's mildly comforting given that 2013 was a recovery year from the carnage of 2012.

There are differences from this year though that may make comparisons unsafe.
Absolutely, the biggest difference probably being surface air temperatures. 2013 was very anomalously cold. This year isn't a scorcher, but it's not exactly cool either.

Minor lows positioned near the Aleutians next week will send warm, moist air towards the Arctic cyclones, which might partly explain their longevity.  This is the first substantial advection of excess heat from the Bering that I've noticed since early in the season.

Storms in June do bring a cooler, cloudier central Arctic and help preserve sea ice but be careful with the 850mb temperatures. There's a very different atmospheric sounding under an upper level low than under an upper level high. There's subsidence, and often an inversion under the high.
   ....

I recall some earlier discussion on the Forum about "cold-core" vs. "warm-core" cyclones.  Not sure whether this pertains to FooW's point, but the one approaching ESS looks like the latter to my layman's eye.

On the whole, my impression is that that the near-term weather will be good for extent (owing mainly to dispersion and cooler central temperatures) but eventually bad for volume, for reasons others have noted.  If that's the case, we're still on thin ice this year.

FishOutofWater

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Re: The 2017 melting season
« Reply #2172 on: June 21, 2017, 04:52:35 PM »
Winter polar lows may have a dominant thermodynamic component, like tropical storms, and could be warm core. Summer lows are cold-core barotropic systems. The key factor here is the warm sector pulled in from outside of the Arctic ocean region. Lows that form on the Siberian shores of the Arctic ocean can pull in lots of hot air from the continent. They can melt the landfast ice out and speed up melt on the shallow Siberian platform.

On the other hand, May, June and July lows bring in thick clouds which reflect sunlight help cool the central Arctic core and preserve the ice.

In 2013 a deep low in July on the CAA side of the Arctic ocean killed all the melt momentum, disrupted the transpolar flow and helped raise the September minimum ice extent. Air pulled by storms from the CAA to the Arctic ocean is generally cold.

We are in the low pressure phase of the Arctic oscillation now but I think it's likely to shift to high pressure around the first of July. The AO is a pretty regular oscillation in the summer. That would mean the central core could melt rapidly in July. See the attached figure of the AO this spring.



Thawing Thunder

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Re: The 2017 melting season
« Reply #2173 on: June 21, 2017, 05:38:21 PM »
The "garlic press" started much earlier in 2017.

How do you come to that conclusion? My understanding is that the term "garlic press" refers to multi-year ice moving from the Central Arctic through the Canadian Arctic Archipelago. Your understanding would seem to be different from mine?

Yes, I referred to export between the archipelagos on the atlantic side. But I think I remember now - you're probably right with your version.
« Last Edit: June 21, 2017, 06:13:35 PM by Thawing Thunder »
The Thunder was father of the first people, and the Moon was the first mother. But Maxa'xâk, the evil horned serpent, destroyed the Water Keeper Spirit and loosed the waters upon the Earth and the first people were no more.

maltose

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Re: The 2017 melting season
« Reply #2174 on: June 21, 2017, 05:42:13 PM »
Neven, you may have stumbled on the way to communicate the melting season and the urgency involved--through the public's stomachs! Hard to resist that! ;) Seriously, you are right that the conditions are worse than last year, and 2016's volume was a near-record.

Neven

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Re: The 2017 melting season
« Reply #2175 on: June 21, 2017, 06:05:13 PM »
Seriously, you are right that the conditions are worse than last year, and 2016's volume was a near-record.

The ice pack distribution may be worse, but if things are cloudy and the snow on the ice is delaying preconditioning anyhow, it may not be enough to get the thinner ice to melt out completely, even if the current cyclone ends up causing a lot of divergence. I'm not sure about how this will play out at all. It's conventional wisdom vs the new normal.

Would you like some sprinkles with that?  ;)
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Lord M Vader

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Re: The 2017 melting season
« Reply #2176 on: June 21, 2017, 06:15:12 PM »
Is it just my eyesight or have the current cyclone dragged so much heat and rain from south that melt ponds are now visible over a big swath of the Russian Arctic as well as the Pacific side? Judge for yourself! I have encircled the approximate areas for this with red as the color there seems to be somewhat bluish.


jplotinus

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Re: The 2017 melting season
« Reply #2177 on: June 21, 2017, 07:36:32 PM »
Bluish you ask?
Tiksi, on the Laptev coast near Lena delta is unquestionable bluish:

seaicesailor

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Re: The 2017 melting season
« Reply #2178 on: June 21, 2017, 07:36:55 PM »
Is it just my eyesight or have the current cyclone dragged so much heat and rain from south that melt ponds are now visible over a big swath of the Russian Arctic as well as the Pacific side? Judge for yourself! I have encircled the approximate areas for this with red as the color there seems to be somewhat bluish.
Nice handwriting LMV :)
I agree with you, also some areas of the Beaufort (close to Alaska) have worsened subtly and not because of the cyclone
Jplotinus the Laptev is done! Unlike last year

johnm33

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Re: The 2017 melting season
« Reply #2179 on: June 21, 2017, 10:02:25 PM »

Lord M Vader

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Re: The 2017 melting season
« Reply #2180 on: June 21, 2017, 10:35:33 PM »
Johnm33: Good question!

FishOutofWater

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Re: The 2017 melting season
« Reply #2181 on: June 21, 2017, 10:38:06 PM »
Terra's lovely shades of 7-2-1 blue show varying degrees of wetness today. Yes, the 721 amplifies what you saw in "true color".

Tigertown

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Re: The 2017 melting season
« Reply #2182 on: June 22, 2017, 03:34:22 AM »
Warm surface air continues to work on the Beaufort and CAA

subgeometer

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Re: The 2017 melting season
« Reply #2183 on: June 22, 2017, 05:06:04 AM »
A few gifs of the Chukchi, ESS and Laptev seas in recent days and there does seeem, as LMV says, to be rmelt ponds appearing across much of the Siberian side, and not just on  the fast ice

Tigertown

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Re: The 2017 melting season
« Reply #2184 on: June 22, 2017, 07:18:20 AM »
It looks as if within a couple weeks, one could leave the Amundsen Gulf in a boat and go around the perimeter of the Arctic, ending up in the Kara Sea. Any volunteers?



Edit: Image became available a couple hours after this post. ESS
« Last Edit: June 22, 2017, 07:59:57 AM by Tigertown »

Often Distant

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Re: The 2017 melting season
« Reply #2185 on: June 22, 2017, 08:17:03 AM »
Petermann glacier is looking extremely brittle. Massive crack appearing clear behind the coastline, which is rather troubling.

Lord M Vader

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Re: The 2017 melting season
« Reply #2186 on: June 22, 2017, 08:21:15 AM »
ECMWF 00z op run: D4 bomb cyclone at 963 hpa. By D3 the pressure is forecasted to be 974 hpa. What do we think about that?


meddoc

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Re: The 2017 melting season
« Reply #2187 on: June 22, 2017, 08:24:11 AM »
[quote ]
ECMWF 00z op run: D4 bomb cyclone at 963 hpa. By D3 the pressure is forecasted to be 974 hpa. What do we think about that?
[/quote]

Hycom also shows Melt Momentum picking up big- time.
Russian side of the Arctic is getting baked (1 m or more Ice being vaporized) almost til the North Pole.

georged

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Re: The 2017 melting season
« Reply #2188 on: June 22, 2017, 08:37:46 AM »
ECMWF 00z op run: D4 bomb cyclone at 963 hpa. By D3 the pressure is forecasted to be 974 hpa. What do we think about that?

Does imported warm air from Siberia and ocean mixing count for more than the significant reduction in insolation during the peak week for sunlight?

Tigertown

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Re: The 2017 melting season
« Reply #2189 on: June 22, 2017, 08:39:23 AM »
ECMWF 00z op run: D4 bomb cyclone at 963 hpa. By D3 the pressure is forecasted to be 974 hpa. What do we think about that?
For the most part, the GFS seems to agree on the day three pressure, at least.

georged

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Re: The 2017 melting season
« Reply #2190 on: June 22, 2017, 08:42:24 AM »
Petermann glacier is looking extremely brittle. Massive crack appearing clear behind the coastline, which is rather troubling.


There's a discussion of Petermann and this subject here:
http://forum.arctic-sea-ice.net/index.php/topic,53.msg117629.html#msg117629]
[url]http://forum.arctic-sea-ice.net/index.php/topic,53.msg117629.html#msg117629
[/url]
Per Espen, these are probably meltponds.

Neven

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Re: The 2017 melting season
« Reply #2191 on: June 22, 2017, 10:16:17 AM »
I've been checking the ECMWF forecast twice a day, and it comes across as somewhat fickle, but the sub-970 hPa low pressure that keeps appearing and disappearing, does seem to be coming closer. I can't wait to see the 12Z and tomorrow's 00Z forecasts.

If such a big cyclone gets followed by high pressure and then another cyclone, things might really start to look like Mike Tyson in his prime.
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Lord M Vader

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Re: The 2017 melting season
« Reply #2192 on: June 22, 2017, 10:38:21 AM »
Neven: the ECMWF ensemble has the bomb cyclone down to 972 hpa. And that's an ENSEMBLE(!)

Cook

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Re: The 2017 melting season
« Reply #2193 on: June 22, 2017, 10:54:21 AM »
It is going to be a relatively deep low. I think plus minus 5hPa is a moot point. I think the real issue is that it going to be slow moving and fairly intense over a long time, many days.

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Re: The 2017 melting season
« Reply #2194 on: June 22, 2017, 11:42:07 AM »
As for clear blue skies versus a low and melt produced?

I imagine rain is far better , and faster, at melting ice than sunshine?

I think if you have 2 blocks of ice , one sat in water in shade but under a constant shower of water and one sat in water in full sun the heat transfer from the constant rain would be greater than the sunshine?
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F.Tnioli

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Re: The 2017 melting season
« Reply #2195 on: June 22, 2017, 12:10:08 PM »
...
If such a big cyclone gets followed by high pressure and then another cyclone, things might really start to look like Mike Tyson in his prime.
You mean beaten? Or biting? =)

...

I imagine rain is far better , and faster, at melting ice than sunshine?

I think if you have 2 blocks of ice , one sat in water in shade but under a constant shower of water and one sat in water in full sun the heat transfer from the constant rain would be greater than the sunshine?
Depends on how much rain it is. It takes LOTS of energy to make the solid-to-liquid transition, - basically same amount of energy per gram as it takes to increase temperature of that gram of water from 0C to 83C. So, let's say rain water comes in at some 5C temperature; then to melt roughly 1 cm of ice thickness, we'd need roughly 16 cm layer of water from such "+5C" rain water to fall. 1 meter of thickness = 16 meters of rainfall. The latter's quite unrealistic, don't you think.

It is not rainfall directly which spells doom for ice; it's related effects which the cyclone produces.

1st, winds cause wave action, steering water column of the ocean - and there is HUGE amount of heat, in most places, stored in that "mixable by strong cyclone" 100 meters water column. Easily enough to melt a meter of ice on the surface.

2nd, rain creates ponds and destroys any remaining snow cover easily, and so after cyclone is gone, much reduced albedo of ponded ice allows sun to melt things times faster.

3rd, whereever ice is in much broken shape already, waves will break it further into smaller pieces, thus increasing total surface of water-ice boundary - and summer-time this can only mean faster melt whenever any warm wind and/or more rain and/or more sunshine and/or warm water current would come next.
« Last Edit: June 22, 2017, 12:21:56 PM by F.Tnioli »

Thawing Thunder

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Re: The 2017 melting season
« Reply #2196 on: June 22, 2017, 12:13:37 PM »
As for clear blue skies versus a low and melt produced?

Without being too scientific: I think it's precise to call such a situation a clusterfuck.
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DrTskoul

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Re: The 2017 melting season
« Reply #2197 on: June 22, 2017, 12:28:09 PM »
...
If such a big cyclone gets followed by high pressure and then another cyclone, things might really start to look like Mike Tyson in his prime.
You mean beaten? Or biting? =)

...

I imagine rain is far better , and faster, at melting ice than sunshine?

I think if you have 2 blocks of ice , one sat in water in shade but under a constant shower of water and one sat in water in full sun the heat transfer from the constant rain would be greater than the sunshine?
Depends on how much rain it is. It takes LOTS of energy to make the solid-to-liquid transition, - basically same amount of energy per gram as it takes to increase temperature of that gram of water from 0C to 83C. So, let's say rain water comes in at some 5C temperature; then to melt roughly 1 cm of ice thickness, we'd need roughly 16 cm layer of water from such "+5C" rain water to fall. 1 meter of thickness = 16 meters of rainfall. The latter's quite unrealistic, don't you think.

It is not rainfall directly which spells doom for ice; it's related effects which the cyclone produces.

1st, winds cause wave action, steering water column of the ocean - and there is HUGE amount of heat, in most places, stored in that "mixable by strong cyclone" 100 meters water column. Easily enough to melt a meter of ice on the surface.

2nd, rain creates ponds and destroys any remaining snow cover easily, and so after cyclone is gone, much reduced albedo of ponded ice allows sun to melt things times faster.

3rd, whereever ice is in much broken shape already, waves will break it further into smaller pieces, thus increasing total surface of water-ice boundary - and summer-time this can only mean faster melt whenever any warm wind and/or more rain and/or more sunshine and/or warm water current would come next.

Rain freezing on ice is what gives the energy...
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slow wing

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Re: The 2017 melting season
« Reply #2198 on: June 22, 2017, 12:35:46 PM »
On viewing the model predictions at tropicaltidbits.com, the models all agree on a strong pressure minimum on or around 00z Monday, June 26 2017.

NAVGEM shows the 'weakest' storm prediction: already relatively strong at 978 hPa.
CMC has the strongest storm, bottoming out at 961 hPa.

The current predictions of the various models for pressure minima are summarised in the attached table.

JayW

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Re: The 2017 melting season
« Reply #2199 on: June 22, 2017, 12:46:54 PM »
Storms (excluding tropical cyclones) generally have warm and cold sectors, unfortunately, it looks like most of the Arctic has been put in the warm sector.

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