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The Walrus

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Re: The 2020/2021 freezing season
« Reply #1100 on: February 10, 2021, 02:58:34 PM »
HYCOM is showing that ice movement as well, but I don't see it going down to Fram. Instead it's being pressed against the SZ islands and the western Laptev coast. And the same thing is going on in the ESS. The ice is piling up there as well.

Last year the ice spun the other way, which left us with an early open Laptev and ESS. So if the ice doesn't make the same reverse spin, the Laptev and ESS could stay frozen for a lot longer this coming melting season because of a big pile up of ice.

Which is a good thing I presume?

I believe so.

gerontocrat

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Re: The 2020/2021 freezing season
« Reply #1101 on: February 10, 2021, 05:37:55 PM »
CryoSat shows that the majority of 3m+ ice in the Arctic is in a triangular wedge from the North Pole tapering to a point East of NE Greenland and West of Svalbard.

GFS also shows that at the moment winds are not favoutable for export via the Fram..

However, if at any time in the next 2 months especially we have a sustained (2 weeks or more?) period of strong export from the Fram I would guess the consequences for the melting season could be significant.
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uniquorn

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Re: The 2020/2021 freezing season
« Reply #1102 on: February 10, 2021, 07:33:02 PM »
The problem lies at the end of this ice circulation, where the CAB mass presses against Greenland and some of it is exiting the Fram, as shown in the Ascat animation a few posts above. Given the blob of thicker ice identified by Cryosat in that region, I find this concerning.
I don't very often run ascat backwards but it looks like that thicker ice came from just below last year's white band. Tricky to be sure with ascat's 'summer whitewash'.

2021 day40 to 2020 day28 (backwards)
Nearly everything between the pole and the fram goes down the fram or melts before it gets there.
« Last Edit: February 10, 2021, 07:59:40 PM by uniquorn »

Niall Dollard

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Re: The 2020/2021 freezing season
« Reply #1103 on: February 10, 2021, 07:59:59 PM »
A GIF comparing PSL ice thicknesses 2020 and 2021, for around this date (needs a click)

The Atlantic side is so weak this year.

Also the PSL thickness this Feb, which is quite similar to the Hycom image up thread, is almost the complete polar (sorry! ) opposite to the Cryosat image for the region between Svalbard and the pole. There must be some big sensing errors somewhere there.

Niall Dollard

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Re: The 2020/2021 freezing season
« Reply #1104 on: February 10, 2021, 08:35:11 PM »
The Feb 2020 image from PSL reminds me of this post at the end of the melt season thread, highlighting what an active season last Spring was for Fram export.

All that thick ice ready to go down the Fram. The extent in the Greenland Sea was quite large with ice reaching Jan Mayen on the 12th May 2020 (the first time sea ice had reached the island since 2004).

Going by the Hycom & PSL thickness images there is much less thick ice in the "holding" area ready to go down the Fram this spring.   

Freegrass

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Re: The 2020/2021 freezing season
« Reply #1105 on: February 10, 2021, 08:49:05 PM »
HYCOM is showing that ice movement as well, but I don't see it going down to Fram. Instead it's being pressed against the SZ islands and the western Laptev coast. And the same thing is going on in the ESS. The ice is piling up there as well.

Last year the ice spun the other way, which left us with an early open Laptev and ESS. So if the ice doesn't make the same reverse spin, the Laptev and ESS could stay frozen for a lot longer this coming melting season because of a big pile up of ice.

Which is a good thing I presume?

I believe so.
I had a theory last season that when there is early melt in the Laptev, the beaufort will met out later. I guess we can test out that theory this year.

If we get a counterclockwise spin of the ice, the beaufort wil fill up with ice, and the Laptev and ESS will lose their ice.

With a clockwise motion of the ice, the reverse happens. The Laptev and ESS will be filled up with ice, and the corner of the beaufort will have thin ice that will melt out early...

Weather can always mess up that theory, but I think it's logical, no?
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gerontocrat

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Re: The 2020/2021 freezing season
« Reply #1106 on: February 10, 2021, 10:12:30 PM »
CryoSat is the only image that shows this big lump of thick ice between NE Greenland and the Pole Not in the Jaxa image either, and the image from DMI is just - weird.

So why is Cryosat showing such a difference?
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oren

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Re: The 2020/2021 freezing season
« Reply #1107 on: February 11, 2021, 12:05:27 AM »
DMI is an unreliable thickness model. Hycom and PIOMAS are more reliable but are still models. JAXA is based on measurement but the result is very unreliable. The only one of the bunch which is both measured and considered reliable is Cryosat, which is why I am concerned.

Freegrass

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Re: The 2020/2021 freezing season
« Reply #1108 on: February 11, 2021, 12:52:49 AM »
Isn't it so that Cryosat is just one measurement from space, while HYCOM uses multiple sources of data to try and produce a more complete model?
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Paul

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Re: The 2020/2021 freezing season
« Reply #1109 on: February 11, 2021, 01:33:30 AM »
HYCOM is showing that ice movement as well, but I don't see it going down to Fram. Instead it's being pressed against the SZ islands and the western Laptev coast. And the same thing is going on in the ESS. The ice is piling up there as well.

Last year the ice spun the other way, which left us with an early open Laptev and ESS. So if the ice doesn't make the same reverse spin, the Laptev and ESS could stay frozen for a lot longer this coming melting season because of a big pile up of ice.

Which is a good thing I presume?

I believe so.
I had a theory last season that when there is early melt in the Laptev, the beaufort will met out later. I guess we can test out that theory this year.

If we get a counterclockwise spin of the ice, the beaufort wil fill up with ice, and the Laptev and ESS will lose their ice.

With a clockwise motion of the ice, the reverse happens. The Laptev and ESS will be filled up with ice, and the corner of the beaufort will have thin ice that will melt out early...

Weather can always mess up that theory, but I think it's logical, no?

There is some truth behind that, I think for alot of the summer last year, the Beaufort was cooler with chilly winds whilst the Siberian Arctic was melting and compacting at a rate of knots. One thing the high pressure did do is compact the ice near the pole, I think if we had a stormy August, we may seen the ice edge get near if not at the pole, that said, it came quite close by September regardless, the retreat was quite spectacular.

The last few years, we seen an area which lost ice at record breaking pace in the early part of the melt season and all indications may suggest its the Barants that could take that title. Baffin Bay also perhaps but more interested in the basin itself. In some ways, I see this year being quite similar to 2018 in which the Siberian side had quite a bit of thicknesses and fast ice due to high pressure. Maybe the Beaufort is a bit thicker also with the multi year ice heading there. Either way, the ice over the Siberian seas could not be more chalk and chesse to last year where not alot compacted and even as early as May, the warning signs were there.

Freegrass

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Re: The 2020/2021 freezing season
« Reply #1110 on: February 11, 2021, 02:37:42 PM »
The difference in the Laptev and ESS between this year and last year is significant. What should be concerning is the lack of thickness between Svalbard and the pole. It looks like the wind blew all the thick ice towards the beaufort. But Cryosat is showing thicker ice there, so lets see how this turns out during the season. I'll be following HYCOM closely...

Click to animate
« Last Edit: February 11, 2021, 02:45:10 PM by Freegrass »
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Glen Koehler

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Re: The 2020/2021 freezing season
« Reply #1111 on: February 11, 2021, 03:15:28 PM »
     A shift in the center of the thick ice from latitude 83 to about 75 must have serious consequences for early season melt.
   
      We usually discuss increased ice mobility with declining thickness and concentration as being important because it could lead to increased losses by Fram or Nares export.  Looking at Freegrass's animation makes me wonder if the geographic shift of the center of the thick ice to the south and west is another manifestation of increased ice mobility with consequences for ASI volume losses. 
   
     Ice that goes out the Fram is a definite loss.  Ice that moves 8 degrees south, but still contained within the Arctic Ocean, is not an immediate or definite loss.  But that latitude shift almost certainly makes that ice more susceptible to being lost during the next melt season.  The difference in solar declination and resulting angle and duration of incident solar radiation in April and May at 75N vs. 83N means that early melt pond development will cause decreased albedo in June and July ("melt pond momentum").  Moving the ice 8 degrees to the south (and closer to land) must also expose it to a warmer spring-summer temperature regime.
« Last Edit: February 11, 2021, 10:19:11 PM by Glen Koehler »

Freegrass

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Re: The 2020/2021 freezing season
« Reply #1112 on: February 11, 2021, 04:51:34 PM »
I think the lesson we can learn from this is that weather dictates everything... We are on a downward trend concerning ASI. And one year we will be above that trendline, while other years we will be below it. And the only reason for that is the weather, and wind patterns.

Yes, thinner ice will make it more mobile. Where it all ends up, depends completely on the wind...
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Niall Dollard

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Re: The 2020/2021 freezing season
« Reply #1113 on: February 11, 2021, 06:16:14 PM »
     A shift in the center of the thick ice from latitude 83 to about 75 must have serious consequences for early season melt.
   

I understand your concerns Glen but I  am not sure where you are referring as "the center". Is this from the above Hycom chart ? The thick green stretches from beyond the pole down to near McKenzie delta at 70 N. That would give a central latt of over 80 N. (Not far off 82N Id say).

But I agree all that thick ice in the Beaufort will struggle next melt season especially between 70N and 75N.

Glen Koehler

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Re: The 2020/2021 freezing season
« Reply #1114 on: February 11, 2021, 10:34:50 PM »
      I was knee-jerk reacting to the large blobs of light-blue 2-2.5 meter thick ice in 2021 vs. 2020 in the Freegrass's HYCOM image.  The areas of green for ice >2.5 meters were so small I didn't give them any attention.  While there are still 2 more months of thickening, the sun is already peeking over the horizon at 75N for 4 hours a day.  That won't happen at 83N until March 2.
 
      Moving 8 degrees latitude to the south in the mid-latitudes makes a huge difference for solar radiation and spring-summer temperature regime, so I assume it has similar consequences in the Arctic.

      The area that HYCOM shows with the bulk of the thickest ice on Feb 10, 2021 was largely melted out in Sept 15, 2020.  So the shift of the center of mass away from north of Ellsemere-CAA towards a new center in the Beaufort Sea and closer to the Alaskan-Canadian coast and MacKenzie River outlet as shown in the Freegrass animation seems like it will create significant extra melting pressure.

      What little there is of the thickest yellow-green ice also moved south.  While ESS has more thick ice in the 2021 image, I don't think any of that will be around by August.  Then again, I may be looking through doom-colored glasses.  The ASI looks more vulnerable than ever to me, and I'm surprised the PIOMAS volume is holding up as well as it is.  The 2020 vs. 2021 comparison shows the area around the North Pole losing substantial thickness, and as Freegrass noted, the retreat of the Atlantic front. 

      The location of the dark blue-black 1.25 meter thick ice in 2020 vs. 2021 is another example.  It was scattered but roughly centered around 80N in 2020, but it's center of mass moved south into the ESS at around 76N in 2021.  Maybe that just means that there will be tougher ice and thus slower melt out in the ESS in summer 2022.  But my guess is that what is left of thicker ice being located in lower latitude/higher melt zones will result in one more step down the trend of less MYI (which once gone won't return), and another increase in the portion of annual late summer open water.
       
From https://forum.arctic-sea-ice.net/index.php/topic,3299.msg300601.html#msg300601


« Last Edit: February 11, 2021, 11:45:04 PM by Glen Koehler »

Niall Dollard

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Re: The 2020/2021 freezing season
« Reply #1115 on: February 12, 2021, 12:22:48 AM »
      I was knee-jerk reacting to the large blobs of light-blue 2-2.5 meter thick ice in 2021 vs. 2020 in the Freegrass's HYCOM image. 

Gotcha. My apologies. I was looking at the wrong chart (forgot to animate). It has moved way south  on Hycom.

Freegrass

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Re: The 2020/2021 freezing season
« Reply #1116 on: February 12, 2021, 12:52:33 PM »
When I saw the ice on this date last year, the blue, 2m thick ice, reminded me of the shape of last years minimum in September. So I had to check with a comparison.

If the 2021 minimum ends up looking anything like todays 2 meter ice, then that'll be news for sure...

WARNING! This message has absolutely zero scientific value!

It'll be interesting though to see how far the ice edge will reach this year. An ice free pole is surely possible with a set-up like this. But like I said so many times before; In the end, it'll all come down to the weather...
« Last Edit: February 12, 2021, 10:22:24 PM by Freegrass »
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Re: The 2020/2021 freezing season
« Reply #1117 on: February 12, 2021, 07:30:23 PM »
When another poster noticed how well a particular day foreshadowed end of season area I checked previous years on the same day. It was apparent no correlation existed. While thicker ice will take longer to melt shape is determined as much by thinner ice which is highly mobile in wind and current. The other factor seems to be location (mainly latitude) some areas seem to melt no matter what and others hold on.

BornFromTheVoid

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Re: The 2020/2021 freezing season
« Reply #1118 on: February 13, 2021, 02:07:33 PM »
Slow animation for the last week. The large opening at the exit of Nares is quite interesting.
(click to play)
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Re: The 2020/2021 freezing season
« Reply #1119 on: February 14, 2021, 03:08:24 AM »
AO decided to whiplash. Looks like it'll turn positive, from a winter low negative.

Euro and GFS predicting low pressure systems coming up Greenland sea, bringing warmth and moisture. Cyclonic winds across pack.

48 hours or so. They're both aligned through 10-day, who knows if that works out, but kinda interesting given state of Atlantic.

uniquorn

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Re: The 2020/2021 freezing season
« Reply #1120 on: February 14, 2021, 11:44:40 AM »
AO decided to whiplash. Looks like it'll turn positive, from a winter low negative.<<>>
Yep, could be interesting over the Yermak Plateau for the next few days.
rammb, band I5, feb13-14  https://col.st/BvcZ5  (click 10MB)

Argo float 7900550 in the West Spitzbergen current north east of Svalbard reporting sea temperatures of around +1C down to 34m depth yesterday. Salinity here

Quote
PLATFORM_CODE   DATE (YYYY-MM-DDTHH:MI:SSZ)   DATE_QC   LATITUDE (degree_north)   LONGITUDE (degree_east)   POSITION_QC   PRES (decibar)   PRES_QC   PSAL (psu)   PSAL_QC   TEMP (degree_Celsius)   TEMP_QC
7900550   2021-02-13T05:11:20Z   1   81.83741   26.70286   1   0   1   34.614   3   0.954   3
7900550   2021-02-13T05:11:20Z   1   81.83741   26.70286   1   0.9   1   34.614   3   0.954   3
7900550   2021-02-13T05:11:20Z   1   81.83741   26.70286   1   1.8   1   34.62   3   0.952   1
7900550   2021-02-13T05:11:20Z   1   81.83741   26.70286   1   2.9   1   34.61   3   0.962   1
7900550   2021-02-13T05:11:20Z   1   81.83741   26.70286   1   3.9   1   34.59   3   0.983   1
7900550   2021-02-13T05:11:20Z   1   81.83741   26.70286   1   5   1   34.608   3   0.957   1
7900550   2021-02-13T05:11:20Z   1   81.83741   26.70286   1   6   1   34.596   3   0.937   1
7900550   2021-02-13T05:11:20Z   1   81.83741   26.70286   1   7   1   34.601   3   0.873   1
7900550   2021-02-13T05:11:20Z   1   81.83741   26.70286   1   8   1   34.596   1   0.876   1
7900550   2021-02-13T05:11:20Z   1   81.83741   26.70286   1   9.1   1   34.599   1   0.867   1
7900550   2021-02-13T05:11:20Z   1   81.83741   26.70286   1   10   1   34.597   1   0.899   1
« Last Edit: February 15, 2021, 01:00:23 PM by uniquorn »

gerontocrat

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Re: The 2020/2021 freezing season
« Reply #1121 on: February 14, 2021, 02:23:42 PM »
GFS says that on Wednesday while Canada and the lower 48 continue to endure foul weather, above zero temperatures attempt to reach the North Pole.
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bbr2315

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Re: The 2020/2021 freezing season
« Reply #1122 on: February 14, 2021, 08:57:52 PM »
The high latitude +500MB anomalies this season appear unprecedented since 2010.

2013, 2014, 2016 come a bit close but none have the consolidated look of 2021, and the massive block funneling PAC heat directly poleward.

Freegrass

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Re: The 2020/2021 freezing season
« Reply #1123 on: February 15, 2021, 01:53:04 PM »
Latest Five Day Forecast
Wind @ Surface
Large GiF!

I haven't done one of these in a while...

It looks like the Atlantic front will be blown more into the basin instead of exiting through Fram. If we don't get another big Fram export event soon, the basin will be filled with lots of ice...

Sure, the thicker ice in the beaufort, ESS, and Laptev will have a lot of melting potential. But in the end, if the ice is thicker, and takes longer to melt out, it'll keep the ocean covered for longer so it can't suck up al that heat from the sun during peak insolation...

The way the arctic is set up right now, I don't see us breaking records this year. Although I do believe we could see weird things happen along the CAA and Atlantic front. The Mega crack could become HUGE this season...
« Last Edit: February 15, 2021, 01:59:28 PM by Freegrass »
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BornFromTheVoid

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Re: The 2020/2021 freezing season
« Reply #1124 on: February 15, 2021, 03:17:58 PM »
The combined Baffin Bay and Gulf of St Lawrence extent is now the lowest on record for Feb 14th.
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Re: The 2020/2021 freezing season
« Reply #1125 on: February 15, 2021, 05:53:32 PM »
The combined Baffin Bay and Gulf of St Lawrence extent is now the lowest on record for Feb 14th.


Yep, this year it's that, another year it was Chucki/Bering and so on, but one day/year it will be several and/or all of them and that will be the year we are trying to guess when it will happen, BOE wise.

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Re: The 2020/2021 freezing season
« Reply #1126 on: February 15, 2021, 06:24:44 PM »
Latest Five Day Forecast
Wind @ Surface
Large GiF!

I haven't done one of these in a while...

It looks like the Atlantic front will be blown more into the basin instead of exiting through Fram. If we don't get another big Fram export event soon, the basin will be filled with lots of ice...

Sure, the thicker ice in the beaufort, ESS, and Laptev will have a lot of melting potential. But in the end, if the ice is thicker, and takes longer to melt out, it'll keep the ocean covered for longer so it can't suck up al that heat from the sun during peak insolation...

The way the arctic is set up right now, I don't see us breaking records this year. Although I do believe we could see weird things happen along the CAA and Atlantic front. The Mega crack could become HUGE this season...
I agree with Freegrass, I am beginning to think 2013 + 2014 are the best analogs to the coming summer, although our end-total #s could be lower than those. Ironically this year could be our best shot at an open North Pole in quite some time in spite of overall higher area and extent numbers.

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Re: The 2020/2021 freezing season
« Reply #1127 on: February 15, 2021, 06:44:19 PM »
And yet when analyzed no correlation was found between low extent at maximum and low extent at minimum. A slight but probably unimportant correlation was found between high extent at maximum and low extent at minimum. Depending on weather Beaufort could melt this year. We still have 6 weeks or so of thickening ice but "Arctic Blasts" in North America mean warmer temperatures in the Arctic. Higher temperatures on top of the ice lead to smaller gradients which result in less ice forming. Thinner ice near the pole seems more worrisome. Early season melting may be slower but mid season melt could proceed quickly. IMO a record minimum at the end of the melt season is very possible. As always weather will decide.

bbr2315

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Re: The 2020/2021 freezing season
« Reply #1128 on: February 15, 2021, 07:36:52 PM »
And yet when analyzed no correlation was found between low extent at maximum and low extent at minimum. A slight but probably unimportant correlation was found between high extent at maximum and low extent at minimum. Depending on weather Beaufort could melt this year. We still have 6 weeks or so of thickening ice but "Arctic Blasts" in North America mean warmer temperatures in the Arctic. Higher temperatures on top of the ice lead to smaller gradients which result in less ice forming. Thinner ice near the pole seems more worrisome. Early season melting may be slower but mid season melt could proceed quickly. IMO a record minimum at the end of the melt season is very possible. As always weather will decide.
Snow extent is now off the +/- 1SD chart for North America, which is a bit more unusual than the SWE deviation (which is also now more than +1SD above seasonal max at about 1,300KM^3).

The impact of a snowier North America on the Arctic is two-fold.

1) A snowier North America tempers advection of airmasses across the continent towards the Beaufort and CAA. Perhaps this is why 2012 was so horrific in these regions as it followed a winter with very LOW extent and SWE in North America, allowing very early intrusion of warm continental airmasses atop these regions.

2) In the presence of significant open water in the highest latitudes and oceanic heat content, a snowier North America assists the disruption of the stratospheric polar vortex (and its tropospheric counterparts), "assisting" the leakage of Arctic airmasses into the continent, which then spill off into the Pacific and, primarily, the Atlantic Oceans. This is a major net NEGATIVE for the CAB and ATL peripheral seas as these airmasses advect the continuing build up of oceanic heat anomalies into the Arctic Ocean proper.

I would guess the situation in eastern Eurasia acts as a similar throttle re: advection of NPAC heat into the Bering / Chukchi.

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Re: The 2020/2021 freezing season
« Reply #1129 on: February 15, 2021, 07:57:16 PM »
And yet when analyzed no correlation was found between low extent at maximum and low extent at minimum.....


That's true if only one (or two) of those seas contribute to that low maximum while I'm talking about the time when 3 or more of them are concerned, which means that there will be no ice to shiift/be blown from one side to the other to cool the seas and there won't be long stretches of ice over which that at times hot air from land masses can cool down before reaching the central arctic.
However, I did not want to brake loole a discussion about things that no-one really knows, just gave in to a thought that I have/had each year that one of the arctic seas was extremely low, thinking what will happen when it will be several or all of them, that's all.


VeliAlbertKallio

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Re: The 2020/2021 freezing season
« Reply #1130 on: February 16, 2021, 03:11:23 AM »
Parliament evidence on impact of melting Arctic Ocean to the cryosphere and sea levels re-issued:
https://www.academia.edu/45128583/MPs_to_review_UKs_role_in_Arctic_sustainability_Pdf_Edition_of_Parliamentary_Evidence_pdf (This was previously difficult to read due to its earlier format.)
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HapHazard

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Re: The 2020/2021 freezing season
« Reply #1131 on: February 16, 2021, 03:25:51 AM »
I'm noticing a sizeable gap in the ice within the Baffin Bay, based on the University of Bremen data.
Yes, very interesting - another poster or two, notably BornFromTheVoid, have previously pointed this out. It looks like it's an actual "event".


SimonF92

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Re: The 2020/2021 freezing season
« Reply #1132 on: February 16, 2021, 11:17:45 AM »
I'm noticing a sizeable gap in the ice within the Baffin Bay, based on the University of Bremen data.
Yes, very interesting - another poster or two, notably BornFromTheVoid, have previously pointed this out. It looks like it's an actual "event".



Hmmm, is that an ice arch in the Smith Sound?

I know we have resident Nares experts who may correct me, but I think that is the North Water Polynya

https://www.researchgate.net/publication/284726335_Multi-Decadal_Variability_of_Polynya_Characteristics_and_Ice_Production_in_the_North_Water_Polynya_by_Means_of_Passive_Microwave_and_Thermal_Infrared_Satellite_Imagery
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uniquorn

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Re: The 2020/2021 freezing season
« Reply #1133 on: February 16, 2021, 11:43:42 AM »
mercator model shows a pulse of higher salinity at 34m depth down the nares strait recently, likely to mix towards the surface as it leaves the strait, possibly another on the way.

The arch lost a few chunks over the last few days.
« Last Edit: February 16, 2021, 11:49:44 AM by uniquorn »

Niall Dollard

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Re: The 2020/2021 freezing season
« Reply #1134 on: February 16, 2021, 01:38:58 PM »

, but I think that is the North Water Polynya

Indeed Simon.

Some other similar occasions from Februaries past. (2006/2014/2020)

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Re: The 2020/2021 freezing season
« Reply #1135 on: February 16, 2021, 05:40:27 PM »


, but I think that is the North Water Polynya

Indeed Simon.

Some other similar occasions from Februaries past. (2006/2014/2020)

I think so too.

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

uniquorn

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Re: The 2020/2021 freezing season
« Reply #1136 on: February 16, 2021, 06:36:55 PM »
Some other similar occasions from Februaries past. (2006/2014/2020)
So the large polynya recently was perhaps mostly due to wind.
56km/h in 2014, 78km/h in 2020 and 89km/h in 2021. (2006 not available)

Quote
DOI: 10.3390/rs71215807
The southern boundary of the polynya is not defined that strictly, as it varies drastically in the course of the winter season [2]. After the initial formation of the ice bridge at Smith Sound, the sea ice south of it experiences a strong advection due to strong northerly winds from the Nares Strait and prevailing southerly ocean currents [8]
« Last Edit: February 16, 2021, 07:12:33 PM by uniquorn »

Niall Dollard

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Re: The 2020/2021 freezing season
« Reply #1137 on: February 16, 2021, 09:37:05 PM »
Nullschool doesnt go back that far, however much as expected, the surface pressure analysis for 9Z 16th Feb 2006 does indicate strong northerly winds heading down through Smith Sound.

There is a tight pressure gradient between Low Pressure off the NW coast of Greenland and a ridge of high pressure over the western CAA. The strong northerly winds do play a significant role in the formation of the North Water polynya.

At Qaanaaq NW Greenland the wind gusted to 126 km/hr at 0Z. 

Aluminium

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Re: The 2020/2021 freezing season
« Reply #1138 on: February 17, 2021, 08:05:50 AM »
January 31 - February 16.

2020.

RikW

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Re: The 2020/2021 freezing season
« Reply #1139 on: February 18, 2021, 09:16:27 AM »
[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

February 17th, 2021:
     13,875,310 km2, a century break drop of -103,507 km2:o

Time to open the melting season thread? ;)

It wouldn't be the earliest maximum and catching up this 100k loss is not a certainty either.

oren

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Re: The 2020/2021 freezing season
« Reply #1140 on: February 18, 2021, 09:25:25 AM »
I find it hard to believe we have seen the maximum, but this is certainly a very remarkable drop.

Niall Dollard

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Re: The 2020/2021 freezing season
« Reply #1141 on: February 18, 2021, 12:21:17 PM »
By the looks of this, a big drop occurred in the Okhotsk. Given it is so far south, it would be hard to see this regained.

Another drop also north of Svalbard in response to the southerlies

BornFromTheVoid

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Re: The 2020/2021 freezing season
« Reply #1142 on: February 18, 2021, 01:04:16 PM »
The last 2 days have seen huge losses in the Sea of Okhotsk due to a powerful storm in the region.
The animation below shows the relatively slow changes in the 10 days leading up to the storm, then the rapid drops.
(click to play)
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

Jim Hunt

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Re: The 2020/2021 freezing season
« Reply #1143 on: February 18, 2021, 05:26:44 PM »
Time to open the melting season thread? ;)

It's possible 2021 will follow in the illustrious footsteps of 2015?

However I suggest that it's more likely that it won't!

Edit - Found Zack's 2021 overview
« Last Edit: February 18, 2021, 06:13:16 PM by Jim Hunt »
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Niall Dollard

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Re: The 2020/2021 freezing season
« Reply #1144 on: February 18, 2021, 08:54:09 PM »
So if we had reached the max on Feb 16th  Zach Labe's chart  would look something like this :

uniquorn

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Re: The 2020/2021 freezing season
« Reply #1145 on: February 18, 2021, 10:27:40 PM »
wipneus amsr2uh 3.125km extent, okhotsk

amsr2-awi-v103 okhotsk, feb16-18 (18 is early, experimental and movement looks incomplete)
« Last Edit: February 18, 2021, 11:19:12 PM by uniquorn »

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Re: The 2020/2021 freezing season
« Reply #1146 on: February 19, 2021, 12:57:26 AM »
 it's a good day to see the ice departing the NE coast of Greenland , and lots more .. with worldview :

https://go.nasa.gov/3drQ93w

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Re: The 2020/2021 freezing season
« Reply #1147 on: February 19, 2021, 09:15:57 AM »
By the looks of this, a big drop occurred in the Okhotsk. Given it is so far south, it would be hard to see this regained.
Nullschool has strong northerly winds blowing in over the Okhotsk with temperatures well below the -11 degrees generally considered necessary for ice formation. So let's not be too hasty!
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BornFromTheVoid

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Re: The 2020/2021 freezing season
« Reply #1148 on: February 19, 2021, 11:04:53 AM »
3 days of change in Okhotsk.
(click to play)
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

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Re: The 2020/2021 freezing season
« Reply #1149 on: February 19, 2021, 11:46:10 AM »
Reality is merely an illusion, albeit a very persistent one - Albert Einstein