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seaicesailor

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Re: The 2016 melting season
« Reply #4400 on: August 28, 2016, 01:03:29 PM »
What surprised me was, how fast the smaller arm on the alaskan side finally vanished. It became smaller and smaller and then, all in a sudden it disappeared within 24 hours, while the ice bridge in the Laptev Sea still exists (not to mention Big Block).
There was no albedo amplification in Laptev sea this year, no warmth from continents no warm currents, ... less than 50 cm thick first year ice that melts very slowly.
Beaufort is the opposite story. Note that Big block was multi year ice, initial estimates of 4 m thickness and more in some areas.
So anything that falls in there, poof.
Maybe we can expect some flash freezing a day or two.
Oh yeah sorry that's caused by the pidgeon's poops on the antenna.

Jim Hunt

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Re: The 2016 melting season
« Reply #4401 on: August 28, 2016, 01:07:19 PM »
But look at how fast open water is progressing towards the anus, I mean North Pole:

I noticed that too Neven:

http://GreatWhiteCon.info/2016/08/the-great-arctic-cyclone-of-2016/#Aug-28

What's left of the sea ice in the Chukchi Sea. Compare & contrast with AMSR2?
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Shared Humanity

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Re: The 2016 melting season
« Reply #4402 on: August 28, 2016, 02:14:41 PM »
It is amazing to watch how fast the ice melts that is being pushed towards the Barents and the Fram. This is very easy to see north of Svalbard.

Edit....Heck, it's easy to see from Svalbard to east of Franz Josef.

BornFromTheVoid

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Re: The 2016 melting season
« Reply #4403 on: August 28, 2016, 03:26:22 PM »
Another massive drop on the daily NSIDC values, down 154k, and down 313k over the last 2 days.

With the 5 day average extent, this makes the 27th the latest date on record that a drop of over 100k has been recorded. The previous record was August 26th in 2008.

crandles

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Re: The 2016 melting season
« Reply #4404 on: August 28, 2016, 04:16:41 PM »
2016,    08,  26,      4.710
2016,    08,  27,      4.537

looks like a change in data for 26th from 4.691 to 4.71 making the one day fall 173k Km^2 

Crocodile23

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Re: The 2016 melting season
« Reply #4405 on: August 28, 2016, 04:51:49 PM »
2016,    08,  26,      4.710
2016,    08,  27,      4.537

looks like a change in data for 26th from 4.691 to 4.71 making the one day fall 173k Km^2

From where(a link would be helpful) do you obtain these data?
Because pointing the mouse cursor to the data on this graph:
http://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/
I get for example 4.800 (million km^2) for August 27 and not  4.537 you say. :-\


BornFromTheVoid

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Re: The 2016 melting season
« Reply #4406 on: August 28, 2016, 05:02:37 PM »
2016,    08,  26,      4.710
2016,    08,  27,      4.537

looks like a change in data for 26th from 4.691 to 4.71 making the one day fall 173k Km^2

Right you are. Looks like they adjusted a few of the recent days. Will update now, thanks.

BornFromTheVoid

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Re: The 2016 melting season
« Reply #4407 on: August 28, 2016, 05:05:41 PM »
From where(a link would be helpful) do you obtain these data?
Because pointing the mouse cursor to the data on this graph:
http://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/
I get for example 4.800 (million km^2) for August 27 and not  4.537 you say. :-\

That graph uses the 5 day trailing average. This is what you're after: ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/north/daily/data/NH_seaice_extent_nrt_v2.csv

2phil4u

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Re: The 2016 melting season
« Reply #4408 on: August 28, 2016, 06:27:54 PM »
Do you think the open water now is anykind of important in n80.
Im not an expert, but this region will have soon very low temperatures and no sun anymore, so it can give heat to atmosphere, better then warmed water driftet full with ice and then isolation during the hole winter.
Looking at for example cfs you see that soon temperatures of -15 arent rare in this region.
Loss of Multiyear ice and volume yes, but better open water there now then fast refreeze over melted fresh water.
Maybe mixing with saltier water isnt this bad because saltier water can lose more energy, because it refreeze later.
But so or so i think season is gone, all now happens in next 2 weeks will not affect the next meltseason, maybe even some storms in say 10 days are good for the ice.
Badest thing that can happen is drifting thick ice over to warm water and then isolating it the winter.

epiphyte

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Re: The 2016 melting season
« Reply #4409 on: August 28, 2016, 07:02:21 PM »
Do you think the open water now is anykind of important in n80.
Im not an expert, but this region will have soon very low temperatures and no sun anymore, so it can give heat to atmosphere, better then warmed water driftet full with ice and then isolation during the hole winter.


Not sure I'm following completely - but wouldn't open water N of 80 with transient surface freezing pull the air temperature up towards freezing point, even in the absence of the sun? One might speculate that in rough seas this might go on for some time due to mixing down as far as 50-100m competing with the heat loss at the surface. If so, that would be a net loss of energy for the whole system, but warmer than usual low-level air temps. I'm far from an expert either, but I would think that the longer the period between sundown and the onset of the hard winter temp. inversion , the slower the refreeze overall?

Nightvid Cole

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Re: The 2016 melting season
« Reply #4410 on: August 28, 2016, 07:29:22 PM »
Do you think the open water now is anykind of important in n80.
Im not an expert, but this region will have soon very low temperatures and no sun anymore, so it can give heat to atmosphere, better then warmed water driftet full with ice and then isolation during the hole winter.


Not sure I'm following completely - but wouldn't open water N of 80 with transient surface freezing pull the air temperature up towards freezing point, even in the absence of the sun? One might speculate that in rough seas this might go on for some time due to mixing down as far as 50-100m competing with the heat loss at the surface. If so, that would be a net loss of energy for the whole system, but warmer than usual low-level air temps. I'm far from an expert either, but I would think that the longer the period between sundown and the onset of the hard winter temp. inversion , the slower the refreeze overall?

From my old pasttime of looking at reanalysis data, I would say this is not significant until at least mid-September.

binntho

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Re: The 2016 melting season
« Reply #4411 on: August 28, 2016, 07:32:12 PM »
Things are looking a bit hectic at the north pole - over 1 dC at noon today (12:00 Z), with 38 km/h winds (10.5 m/s)

Apocalypse4Real

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Re: The 2016 melting season
« Reply #4412 on: August 28, 2016, 08:39:38 PM »
The Great Arctic Cyclone is churning ice in areas with sea surface temperature anomalies that will accelerate melt and drop extent and area.

See: http://www.megiddo666.apocalypse4real-globalmethanetracking.com/2016/08/great-arctic-cyclones-of-2016.html


Lord M Vader

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Re: The 2016 melting season
« Reply #4413 on: August 28, 2016, 10:32:23 PM »
DMI graph +80N is rather bizarre and the temps have once again, at least briefly, exceeded freeze point. The only other year that have seen a similar behavior is 1984. In 1971 there was also a strong late season surge of warm air but the temps didn't exceed the freeze point.

See: http://ocean.dmi.dk/arctic/meant80n.uk.php

Arcctic continues to surprise us!

P-maker

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Re: The 2016 melting season
« Reply #4414 on: August 28, 2016, 10:41:05 PM »
Normally, when the late summer temperature flatlines, it is called the "shoulder" season. This year however, I think the shoulder is broken...

Nick_Naylor

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Re: The 2016 melting season
« Reply #4415 on: August 28, 2016, 11:21:41 PM »
I don't know about that . . . with a little enhancement, the long-awaited cleavage is obvious, and both shoulders looks OK to me 8)

seaicesailor

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Re: The 2016 melting season
« Reply #4416 on: August 28, 2016, 11:41:59 PM »

Arcctic continues to surprise us!
Isn't it amusing, that two weeks ago we were alarmed by the possibility of a cyclone ~970 hPa, and now there they go, every other day happily crossing the Arctic?

werther

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Re: The 2016 melting season
« Reply #4417 on: August 28, 2016, 11:48:13 PM »
I’ve been away for a few days. But being back, I see the ECMWF forecast last Monday has been realized this weekend.  The strong ridging did bring a pulse of warmth at 850Mb and probably the last (tropospheric) melt situation.

MODIS does show the ‘wrangel arm’ under severe pressure. A couple of days of strong winds remain to have an impact on the definitive outcome of this season. During those days, the 850Mb temps will get back to ‘normal’ and the beep on the DMI +80dgN graph will vanish.

Last Monday I doubted this would be enough to get SIE under the 4Mkm2 threshold.

But while going over the MODIS tiles in CAD, I don’t see much significant ice left beyond a boundary encircling 3.5Mkm2. 
So, when and if IJIS numbers get back on line, there’s reason to expect that number is getting very close to ’07. Maybe under that benchmark by Thursday. The loose spread everywhere is remarkable…

FishOutofWater

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Re: The 2016 melting season
« Reply #4418 on: August 29, 2016, 01:24:57 AM »
Remember, it's not just the loss of ice but the bite that's encroaching the pole is the result of accelerated transport of ice and water across the Arctic. Inflow from the Pacific has been low this year but inflow from the Atlantic has been way above normal as has outflow through the channels of the Canadian archipelago.

The net effect is that cold fresh water is flowing out of the Arctic ocean and warm salty water is flowing in. And if you look at the big picture the heat content in the tropical Atlantic has gone to record levels this year. That heat is going to continue to flow into the Arctic.

The one ocean that is cold is the southern ocean around Antarctica. And that's really bad news because the southern half of the thermohaline circulation is collapsing as basal melting is creating a fresh surface layer that inhibits deep convection. That means more melting from intermediate water there with less heat loss to the atmosphere while the ocean heat moving north increases.

It's going to be very interesting how the weather responds to all the excess heat and ice loss in the northern hemisphere. Meanwhile, where I live, hurricane season is heating up. Will we get another system like Sandy that curves back because of a blocking high that is more likely because sea ice is missing?

It's not just a matter of a little less ice near the pole. It's a global problem and what we see near the pole is one manifestation of excess heat in the system.

TerryM

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Re: The 2016 melting season
« Reply #4419 on: August 29, 2016, 01:35:04 AM »
High wind and coriolis are packing lots of ice into it's last refuge across the top of Canada & Greenland. I so hope the passengers and crew aboard Crystal Serenity won't be discomforted.
Piomas will be interesting.
Terry

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Re: The 2016 melting season
« Reply #4420 on: August 29, 2016, 02:24:54 AM »
The one ocean that is cold is the southern ocean around Antarctica. And that's really bad news because the southern half of the thermohaline circulation is collapsing as basal melting is creating a fresh surface layer that inhibits deep convection. That means more melting from intermediate water there with less heat loss to the atmosphere while the ocean heat moving north increases.

For what it is worth: (a) while the surface of the Southern Ocean is now consistently anomalously cool, the deep waters of the Southern Ocean are warming faster than any other ocean on Earth (which accelerates ice melting in key Antarctic marine glaciers); and (b) the fact that the southern half of the thermohaline circulation is in the process of collapsing also means that the resulting slowdown in the speed of the global conveyor belt will result in the tropics heating faster (which will increase the strength of the atmospheric Hadley Cell and will accelerate the current poleward migration of high altitude clouds; which will allow more solar radiation to heat the topics still faster).
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Adam Ash

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Re: The 2016 melting season
« Reply #4421 on: August 29, 2016, 03:20:57 AM »
Thanks ASLR!  So apart from that everything is fine.  Good to hear.  (!!!$%^%$#$#@!!!)

AbruptSLR

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Re: The 2016 melting season
« Reply #4422 on: August 29, 2016, 03:40:47 AM »
Thanks ASLR!

You can thank Hansen et. al. (2016), as they are the ones who documented this positive feedback mechanism:

https://forum.arctic-sea-ice.net/index.php/topic,1327.0.html
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Lord M Vader

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Re: The 2016 melting season
« Reply #4423 on: August 29, 2016, 03:46:57 AM »
IJIS seems to be up again, hopefully slowly starting to produce values. 4,749 for August 24.... Down ~70K from August 23.

JayW

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Re: The 2016 melting season
« Reply #4424 on: August 29, 2016, 04:20:16 AM »
6 day loop

http://feeder.gina.alaska.edu/search?utf8=✓&search%5Bsensors%5D%5B3%5D=1&search%5Bfeeds%5D%5B5%5D=1&search%5Bstart%5D=&search%5Bend%5D=&commit=Search
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Tigertown

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Re: The 2016 melting season
« Reply #4425 on: August 29, 2016, 04:46:21 AM »
IJIS seems to be up again, hopefully slowly starting to produce values. 4,749 for August 24.... Down ~70K from August 23.
They brought it current now. I will wait on Espen in his thread to be first, but you are not going to believe!

Michael Hauber

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Re: The 2016 melting season
« Reply #4426 on: August 29, 2016, 06:28:33 AM »
The one ocean that is cold is the southern ocean around Antarctica. And that's really bad news because the southern half of the thermohaline circulation is collapsing as basal melting is creating a fresh surface layer that inhibits deep convection. That means more melting from intermediate water there with less heat loss to the atmosphere while the ocean heat moving north increases.

The reason why the southern ocean is anomalously cool is due to intensification of the atmospheric circulation above Antarctica.  This wind blows the ice away from the continent and causes it to expand, and also cools the water.  This wind also brings up more water from below, which results in increased melting of the edges of ice sheets/glaciers (as the water while cold is warm compared to ice).  Finally the southern THC is driven by sea ice formation, and wind driven cooling/evaporation of water near the continents exposed as wind blows the ice away from the continent.  Therefore I would expect the impact of these changes to circulation would be to intensify the THC and not cause it to collapse.
Climate change:  Prepare for the worst, hope for the best, expect the middle.

Bruce Steele

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Re: The 2016 melting season
« Reply #4427 on: August 29, 2016, 07:59:32 AM »
Michael, If you might forgive me finding links and rather continue a few logical arguments please allow me.  Bottom water formation is very dependent on location , it  tends to form close the the Antarctic continent  where  ,like you say , cold offshore winds create frazil ice and squeeze out very cold saline water that sinks. Where that water sinks is important or bottom water would form in more areas than it currently does.  It needs to sink onto shelf bottom where it can travel down canyons to depth. If fresh water and cold push the ice edge too far offshore the frasil ice still forms but as the extruded saline water sinks it mixes with the fresh water lens near the surface and further down warm Circumpolar Current waters brought up via divergence. Small scale mixing processes and  eddies dilute the cold /very saline water with fresh and relativly warm water  as it has to sink through a greater distance  before it hits the bottom where it can travel down the canyons that currently carry it deeper. So the distance the saline water drops affects its ability to maintain its density. It isn't that it fails completely because polynyas still will on occasion form closer to shore in locations that favor bottom water formation like the one that some years form in the Weddell but too many formation sites won't work often enough and AABW will slow.

binntho

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Re: The 2016 melting season
« Reply #4428 on: August 29, 2016, 08:34:54 AM »
The southernmost tip of the eastern Wrangel arm can be seen on Modis quite clearly. The thick white edges would probably be wind driven slush I guess, while the rest of the ice doesn't look too healthy. New Siberian Islands at the top. The second image is Nullschool of the same area from further out at 03:00Z this morning. The marked location is well within the slushy ice in the Modis image, just below the lower edge of the image.

Lord M Vader

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Re: The 2016 melting season
« Reply #4429 on: August 29, 2016, 08:43:45 AM »
Tigertown: you were right, I had hard to swallow the very low number which meant that the SIE on average dropped ~75K during the four days IJIS was down.

From now and until the minimum, both 2007 and 2012 lost about 450K while the lowest post-2007 years saw about 250-200K loss. All this means that we should end up somewhere about 3,9-4,2 Mn km2. I think it more or less will be a dead heat between 2007 and 2016 in the very end. 2007 had a tremendeous amount of preconditioning. 2016 OTOH has a Wrangel arm that seems to be able to go "poof" at any time the next 1-2 weeks.

The most worrysome thing is the fact that 2016 is able to end up in either 2nd or 3rd place given the lack of preconditoning and cloudy weather during the most important time of melting season.

What will happen the next time when we get a new 2007? Speaking of 2007, a "perfect melt season", a 10 by 10, would be record high temps with a good dipole during May-July followed by 1-2 GACs by early-middle of August combined with high temps.


seaicesailor

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Re: The 2016 melting season
« Reply #4430 on: August 29, 2016, 09:17:35 AM »
... Inflow from the Pacific has been low this year but inflow from the Atlantic has been way above normal ...
I can't find real-time data out there and I'd love to. I am not so concerned with the overall flow budget in the Arctic, but with short-term effects (weeks to couple of months) on the Pacific side.

I read this from the latest ASI News and Analysis. It doesn't say more, less, or high or low, but it finds this year's warming of waters way north unusual and maybe linked with ocean currents (not necessarily from Bering directly though).

http://nsidc.org/arcticseaicenews/

"Early ice retreat has allowed the ocean to warm, both from absorption of the sun’s energy and from northward-flowing warm water in the Chukchi Sea to the west of Alaska and in the Barents Sea to the north of Norway. "
...
"What is quite unusual this year is the early ice retreat and resulting ocean warming in the western Beaufort Sea and in the western East Siberian Sea. The extent of warming to the north of these two seas is also unusual, as well as the extent of this warming to the north. These two areas typically melt out later in the season, when atmospheric heating rates have declined from their mid-summer peak. Thus the exposed ocean warms, but not all that much. This pattern was true during the record-setting year of 2012, when by the end of summer, these areas were substantially cooler than surrounding seas that had melted out earlier."

"This year, however, the melt out was early and extensive enough that the ocean has already warmed substantially in these two areas. More sea ice retreat is probable in the western Beaufort and East Siberian seas as well as areas in the coming weeks. But what about the ocean’s response? Some warm water might move northward via ocean currents and contribute to ice melt. However, further dramatic ocean surface warming is unlikely, given that the atmosphere is already cooling, especially in far northern latitudes."

Sourabh

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Re: The 2016 melting season
« Reply #4431 on: August 29, 2016, 09:32:30 AM »
Guys,

I have a question. Which kind of pressure arrangement would be more severe for ice: current one in which low pressure at the pole and high pressure in the surrounding areas OR high pressure at the pole and low pressure in the surrounding areas (edit: as I think was in 2007/2012)?

If this question has been answered before, please point me to that post/thread.

Thanks,
Sourabh

werther

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Re: The 2016 melting season
« Reply #4432 on: August 29, 2016, 09:33:20 AM »
Binntho, hi,
What is visible on Worldview is the SE part of the 'Laptev-arm'. Indeed a wind-driven boundary of slush and rubble to the N. Nothing significant volume-wise. But that whole swath of about 320K km2 is what makes the big difference with '12 extent-wise.

binntho

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Re: The 2016 melting season
« Reply #4433 on: August 29, 2016, 09:36:26 AM »
Binntho, hi,
What is visible on Worldview is the SE part of the 'Laptev-arm'.
Sorry my mistake!

Andreas T

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Re: The 2016 melting season
« Reply #4434 on: August 29, 2016, 11:05:05 AM »
...

"Early ice retreat has allowed the ocean to warm, both from absorption of the sun’s energy and from northward-flowing warm water in the Chukchi Sea to the west of Alaska and in the Barents Sea to the north of Norway. "
...
"What is quite unusual this year is the early ice retreat and resulting ocean warming in the western Beaufort Sea and in the western East Siberian Sea. The extent of warming to the north of these two seas is also unusual, as well as the extent of this warming to the north. These two areas typically melt out later in the season, when atmospheric heating rates have declined from their mid-summer peak. Thus the exposed ocean warms, but not all that much. This pattern was true during the record-setting year of 2012, when by the end of summer, these areas were substantially cooler than surrounding seas that had melted out earlier."

"This year, however, the melt out was early and extensive enough that the ocean has already warmed substantially in these two areas. More sea ice retreat is probable in the western Beaufort and East Siberian seas as well as areas in the coming weeks. But what about the ocean’s response? Some warm water might move northward via ocean currents and contribute to ice melt. However, further dramatic ocean surface warming is unlikely, given that the atmosphere is already cooling, especially in far northern latitudes."
The clouds mean several images would be necessary to give a really good overview but here is a partially transparent overlay of IR on visible  with colour scale squashed to 265 -285K.
There is very warm water along the coast, much of the Beaufort surface is not dramatically warm but the heat absorbed over the summer is spread through a fairly thick layer which still has the ability to melt ice if it gets to it.
worldview link is http://go.nasa.gov/2bTMcVZ to chose your own set up

slow wing

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Re: The 2016 melting season
« Reply #4435 on: August 29, 2016, 11:40:14 AM »
An impressive pressure difference of 64 hPa across the Arctic Basin occurred at 00z on 29 August 2016. Attached is the ECMWF pressure map showing a 975 hPa low north of Svalbard opposed by a 1039 high just inside the Bering Strait.

Is that a record pressure difference observed inside the Arctic Basin during the melt season? Probably could only have been exceeded earlier this season or else during the GAC 2012.

Also attached is the Nullschool wind and temperature map for today showing the strong wind field produced by that set-up, with winds blowing from the Siberian side to the Canadian side over almost all of the Arctic Basin.

iceman

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Re: The 2016 melting season
« Reply #4436 on: August 29, 2016, 12:34:19 PM »
I think that just like the ulna, the radius part of the arm is going to melt out completely, whereas the humerus is going to be pushed into the shoulder:

Sounds right, but the latter will be reduced to a stump upon twin impacts of heat from the mainland and wave action along the eastern edge of the V of open water.

greatdying2

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Re: The 2016 melting season
« Reply #4437 on: August 29, 2016, 12:45:59 PM »
Binntho, hi,
What is visible on Worldview is the SE part of the 'Laptev-arm'. Indeed a wind-driven boundary of slush and rubble to the N. Nothing significant volume-wise. But that whole swath of about 320K km2 is what makes the big difference with '12 extent-wise.

Exactly. Extent is the least useful metric (unless perhaps you happen to be sailing), yet everyone seems so fixated on it.
The Permian–Triassic extinction event, a.k.a. the Great Dying, occurred about 250 million years ago and is the most severe known extinction event. Up to 96% of all marine species and 70% of terrestrial vertebrate species became extinct; it is also the only known mass extinction of insects.

Jim Hunt

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Re: The 2016 melting season
« Reply #4438 on: August 29, 2016, 02:10:09 PM »
The latest Canadian Ice Service chart of sea ice concentration in their sector of the CAB:

http://GreatWhiteCon.info/2016/08/the-great-arctic-cyclone-of-2016/#Aug-29
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

crandles

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Re: The 2016 melting season
« Reply #4439 on: August 29, 2016, 02:42:55 PM »
https://lance.modaps.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r05c04.2016242.terra.1km

looks pretty stirred up by recent storms. Will Tiski show a methane spike as a result?

slow wing

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Re: The 2016 melting season
« Reply #4440 on: August 29, 2016, 02:56:25 PM »
Attached are a couple more NASA EOSDIS Worldview satellite pictures, true colour view from the Terra Satellite for today, 29 August 2016:
 1) The Russian side of the Arctic; and
 2) zoom-in to the remaining ice in and around the Laptev Sea.

For the second image, the ice on the left hand side might well be brash ice. However, the rest looks like a rubble of floes ~1-10 km across - getting progressively denser in packing fraction from left to right - that might well survive the melt season.

It will be interesting to see whether or not the forecast strong winds in that region over the next few days can wipe out any of that rubble.
« Last Edit: August 29, 2016, 03:17:15 PM by slow wing »

werther

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Re: The 2016 melting season
« Reply #4441 on: August 29, 2016, 03:56:27 PM »
Ah yes, Slowwing, that illustrates the state of the 'Laptev-arm'. I don't think much of that arm will vanish in this stage of the season.
Extent is about 320K km2 larger than that during '12 out there. Most of it is dispersed FYI, largest floes about 80km2, median 4km2, lots of small rubble in between. Only the 96K km2 wind-packed floes on the leeward side of Severnaya Zemlya is substantive.

Hi Crandles, I see you saw the brown swath over the ESS continental shelf. Algae and silt but in a density I can't remember having seen there before.

Lord M Vader

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Re: The 2016 melting season
« Reply #4442 on: August 29, 2016, 06:01:16 PM »
Well, I don't think either that the "Laptev arm" will vanish much for the rest of the melting season. However, rain and hard winds during the next couple of days may put some damage to the ice but not enough to make it vanishing at this stage. One caveat is the area north of New Siberian Islands which just maybe will disappear. If the very warm water west of Severnaya Zemlya moves into the Laptev Sea it could have some effect on the ice which should be quite thin FYI there.


slow wing

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Re: The 2016 melting season
« Reply #4443 on: August 30, 2016, 01:18:25 AM »
A low pressure system is currently parked right next to the Severnaya Zemlya islands, so the Laptev arm of the sea ice is getting hit with warm winds up to 50 km/h and maybe some waves.

Will this be its final test before surviving to freeze-over?

bbr2314

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Re: The 2016 melting season
« Reply #4444 on: August 30, 2016, 01:28:34 AM »
A low pressure system is currently parked right next to the Severnaya Zemlya islands, so the Laptev arm of the sea ice is getting hit with warm winds up to 50 km/h and maybe some waves.

Will this be its final test before surviving to freeze-over?
I don't think so. If the EURO is correct then through D10 we will still be pressing the pedal on melt.

It looks like the increasing areas of open ocean are now forcing the polar vortex to retreat to Greenland as more persistent 500mb blocking endures over the Arctic (especially the Siberian/Pac sides at the moment).

To my eyes it seems everything outside the Triangle of Fortitude is going to be blowtorched with warm continental air pretty much straight through D10. Maybe it's only slightly below freezing but with yawning gaps of open water in the main pack, that is hardly sufficient to halt bottom-melt, which is now occurring aided by the failure of the Halocline over certain regions.

Given what we are seeing forecast through D10, I think we will have melt momentum for at least one or two weeks past that point, if not three or four. Compaction is now beginning immediately N of Greenland and the CAA but elsewhere the ice is still moving while losing mass, rather than accreting into any kind of meaningful agglomeration.


BornFromTheVoid

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Re: The 2016 melting season
« Reply #4445 on: August 30, 2016, 08:06:14 AM »
Looks like the winds have been pushing more ice from the central Arctic into the CAA. With the forecast showing below average temps dominating the CAA from about day 4 onward, it will be interesting to see what effect this had.

Jim Hunt

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Re: The 2016 melting season
« Reply #4446 on: August 30, 2016, 11:29:45 AM »
The failure of the Halocline over certain regions.

Which regions?
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Neven

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Re: The 2016 melting season
« Reply #4447 on: August 30, 2016, 12:26:41 PM »
Latest entry on the ASIB: 2016 Mega-Dipole
Il faut comparer, comparer, comparer, et cultiver notre jardin

iceman

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Re: The 2016 melting season
« Reply #4448 on: August 30, 2016, 12:39:10 PM »
Looks like the winds have been pushing more ice from the central Arctic into the CAA. With the forecast showing below average temps dominating the CAA from about day 4 onward, it will be interesting to see what effect this had.

Another 5-6 days to come of the same.  (Looks to me like temps will drop over the CAA islands, but over most of the water will remain normal-to-above for the next week.) 
     Yet another indicator of a substantial drop in ice volume for late August.

A-Team

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Re: The 2016 melting season
« Reply #4449 on: August 30, 2016, 01:28:32 PM »
Here is 10 July 2016 up to 29 Aug 16: