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Bill

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Re: The 2020/2021 freezing season
« Reply #1350 on: March 07, 2021, 10:14:32 PM »
Now that NSIDC extent is back up and running I’ve got the lowest period figures for Feb 28th. I took the higher of Feb 19th & 22nd for the missing data though they are much the same.

Rather to my surprise but as predicted by some here (Gerontocrat?) the lowest 12-month average set on 23rd April 2017 was surpassed on Feb 27th and is continuing to fall – we are currently in the lowest year in the satellite era. (Also true for every other whole-year period.)

If someone can point me to NSIDC daily area and/or JAXA area/extent I’ll do those too.

Ktb

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Re: The 2020/2021 freezing season
« Reply #1351 on: March 08, 2021, 02:18:24 AM »
Hi Bill,

You might want to try this thread

https://forum.arctic-sea-ice.net/index.php/topic,2909.100.html
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oren

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Re: The 2020/2021 freezing season
« Reply #1352 on: March 08, 2021, 02:50:59 AM »
Here is Bill's table in image form, for easier viewing.
Click to enlarge.


VeliAlbertKallio

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Re: The 2020/2021 freezing season
« Reply #1353 on: March 08, 2021, 03:59:38 AM »
I'd conclude from your animation that both Baffin Bay and triangle (NE Greenland - North Pole -Svalbard) show interesting conditions with rather heavy loss areas / sea ice breakage. Southbound ice streaming in both sides of Greenland is evident. Difficult to say whether February anomalies were important, ice generation in February is larger than in March if there is a later swing to ice forming conditions. 

Slow animation for the week. Bering Sea fluctuating with the storms, regrowth in Okhotsk, Barents and Greenland Seas. The continuation of ice free conditions in the Gulf of St Lawrence and losses in Baffin Bay are interesting.
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BornFromTheVoid

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Re: The 2020/2021 freezing season
« Reply #1354 on: March 08, 2021, 05:09:44 PM »
February 2021 had the joint 7th lowest extent on record.

1,332,000 km2 below the 1980s
1,052,000 km2 below the 1990s
485,000 km2 below the 2000s
9,000km2 above the 2010s

(click to play)
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

gerontocrat

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Re: The 2020/2021 freezing season
« Reply #1355 on: March 08, 2021, 06:58:53 PM »
Now that NSIDC extent is back up and running I’ve got the lowest period figures for Feb 28th. I took the higher of Feb 19th & 22nd for the missing data though they are much the same.

Rather to my surprise but as predicted by some here (Gerontocrat?) the lowest 12-month average set on 23rd April 2017 was surpassed on Feb 27th and is continuing to fall – we are currently in the lowest year in the satellite era. (Also true for every other whole-year period.)

If someone can point me to NSIDC daily area and/or JAXA area/extent I’ll do those too.
Hullo Bill,  (I was tempted to write Dear Bill - do you remember a famous Private Eye column from the days of Maggie?)

You can access the download of JAXA EXTENT data here

https://ads.nipr.ac.jp/vishop.ver1/vishop-extent.html
https://ads.nipr.ac.jp/vishop/#/extent/&time=2021-03-07%2000:00:00

In the early years data was only given every other day. I copied the data into my computer then it took a bit of work to fill the gaps with interpolation (and I deleted the 29 Feb line to give me a standard 365 day year)

You can access a variety of NSIDC data files directly from here
ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/seaice_analysis/

or via https://nsidc.org/arcticseaicenews/sea-ice-tools/ (scroll down to find the files)

The files are ftp so not accessible using google. I use Firefox now - though that may not work later this year.

have fun,

Gero
« Last Edit: March 08, 2021, 08:17:56 PM by gerontocrat »
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The Walrus

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Re: The 2020/2021 freezing season
« Reply #1356 on: March 08, 2021, 11:32:42 PM »
February 2021 had the joint 7th lowest extent on record.

1,332,000 km2 below the 1980s
1,052,000 km2 below the 1990s
485,000 km2 below the 2000s
9,000km2 above the 2010s

(click to play)

Interesting that last month was equal to the average over the past 17 years (7 were lower, 8 were higher, and 2 were about equal).  Any thoughts on that?

Aluminium

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Re: The 2020/2021 freezing season
« Reply #1357 on: March 09, 2021, 07:35:32 AM »
September 8 - March 8.

Killian

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Re: The 2020/2021 freezing season
« Reply #1358 on: March 09, 2021, 02:34:38 PM »
The extremely tentative new JAXA maximum extent is 14.14 million km² on March 5th:

https://GreatWhiteCon.info/2021/02/the-2021-maximum-arctic-sea-ice-extent/#Mar-07

Plus the GOFS drift forecast which shows the cyclone mentioned by Pavel.

Click to animate.

Based on the AO, anything before sometime between the 12th and 16th is speculative, imo. The runs are tighly bunched at +6 around the 12th-ish!

Bill

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Re: The 2020/2021 freezing season
« Reply #1359 on: March 09, 2021, 04:17:14 PM »
Thanks Gero. Very useful.

Yes I do remember Dear Bill, penned (apparently) by the appropriately-initialled DT

Bill

gerontocrat

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Re: The 2020/2021 freezing season
« Reply #1360 on: March 09, 2021, 05:29:37 PM »
The extremely tentative new JAXA maximum extent is 14.14 million km² on March 5th
Based on the AO, anything before sometime between the 12th and 16th is speculative, imo. The runs are tighly bunched at +6 around the 12th-ish!
This is the  time of year when extent and area values are in a dither, and a lot of people on this forum get in a dither about calling for the melting thread to open. But we live in an arctic sea ice  world where if anything uncertainty increases.

JAXA Data

If you take the simple average of the dates of the last 10 years maxima, you get an averge date of the 8th march for the maximum. BUT, if you look at extent change day by day for each of the last 10 years, the average maximum is on the 15th March at 14.23 million km2.

(Images attached)

NSIDC Data

The current maximum of NSIDC one day data is 14.78 million km2 on the 4th March, 100k more than the current vaue of 14.68 million km2 (8th March).

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Jim Hunt

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Re: The 2020/2021 freezing season
« Reply #1361 on: March 10, 2021, 02:44:49 PM »
The most recent in the current sequence of cyclones appears to have bottomed out with a central MSLP of 960 hPa according to Environment Canada:

https://GreatWhiteCon.info/2021/02/the-2021-maximum-arctic-sea-ice-extent/#Mar-10

Quote
By way of comparison note that the “Great Arctic Cyclone” of August 2012 reached a minimum MSLP of 966 hPa.
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Freegrass

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Re: The 2020/2021 freezing season
« Reply #1362 on: March 11, 2021, 02:41:28 PM »
Latest Five Day Forecast
Wind + Temp @ Surface
Large GiF!

I don't see a maximum just yet in the HYCOM model, but we must be getting close in the coming days.
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Rodius

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Re: The 2020/2021 freezing season
« Reply #1363 on: March 11, 2021, 11:20:41 PM »
That thickness graphic concerns me a lot.

It looks like the minimum ice could end up in the Beaufort Sea and the North Pole could be open water.

be cause

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Re: The 2020/2021 freezing season
« Reply #1364 on: March 12, 2021, 12:09:00 AM »
 there is a remarkably clear view of much of the Arctic ocean today on worldview .. well worth a closer look . The storm has certainly had it's impact . Wide crack opened N. of Asia and flow thru Fram has taken off ..

 https://go.nasa.gov/3vbEnRj
2007 + 5 = 2012 + 4 = 2016 + 3 = 2019 + 2 = 2021 + 1 =  ' if only we could have seen it coming ' ...

Paul

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Re: The 2020/2021 freezing season
« Reply #1365 on: March 12, 2021, 01:43:03 AM »
That thickness graphic concerns me a lot.

It looks like the minimum ice could end up in the Beaufort Sea and the North Pole could be open water.

Obviously alot will depend on weather conditions but I don't anticipate an ice free pole this year. Given how much heat there was in the Arctic last year, there was still ice at the pole albeit quite thin. All that said, given that the ice around or near the pole this year is not looking all that thick, there is a higher chance of dispersion in this area like in 2013 and 2016 if cyclones are dominant. Still some time for the ice to thicken mind and the current weather pattern will probably help with that because of ice movement and temperatures although fram export tends to increase with this pattern.

Freegrass

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Re: The 2020/2021 freezing season
« Reply #1366 on: March 12, 2021, 02:09:00 AM »
A comparison GIF of the ice on March 9 2020 and 2021.

Without an extreme weather event, I don't see us breaking any records this year with all that ice along the Siberian coast and in the Beaufort sea. Although the Atlantic side and Canadian coast does look worrying...

Click to play
« Last Edit: March 12, 2021, 02:27:32 AM by Freegrass »
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Jim Hunt

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Re: The 2020/2021 freezing season
« Reply #1367 on: March 12, 2021, 09:40:29 AM »
Fram export tends to increase with this pattern.

Indeed it does! Here's the ECMWF Arctic cyclone forecast for midnight tonight UTC.

953 hPa over the Kara Sea accompanied by 970 hPa over the Bering Sea:
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Jim Hunt

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Re: The 2020/2021 freezing season
« Reply #1368 on: March 12, 2021, 10:10:53 AM »
A comparison GIF of the ice on March 9 2020 and 2021.

An alternative comparison.

Click to enlarge/animate
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Freegrass

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Re: The 2020/2021 freezing season
« Reply #1369 on: March 12, 2021, 11:23:29 AM »
A comparison GIF of the ice on March 9 2020 and 2021.
An alternative comparison.
Thanks for that Jim. Mine shows more ice in some places, while yours shows less. It'll be interesting to see how this develops during the rest of the season.

One thing they both agree on though is how little ice there is along the CAA. With a little unluck (is that even a word? ::) ) we could see a huge mega crack appear this season. It certainly doesn't look good for MYI...
« Last Edit: March 12, 2021, 12:59:18 PM by Freegrass »
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BornFromTheVoid

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Re: The 2020/2021 freezing season
« Reply #1370 on: March 12, 2021, 12:07:50 PM »
A look at the huge variability in the Bering Sea and the Sea of Okhotsk over the last month.
(click to play)
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

Shared Humanity

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Re: The 2020/2021 freezing season
« Reply #1371 on: March 12, 2021, 02:24:11 PM »
A comparison GIF of the ice on March 9 2020 and 2021.

Without an extreme weather event, I don't see us breaking any records this year with all that ice along the Siberian coast and in the Beaufort sea. Although the Atlantic side and Canadian coast does look worrying...

Click to play

The ESS will melt out completely. There will be little to no ice from the Chukchi to the Kara. Beaufort could hold out, especially if ice north of the CAA migrates to it which is usually the case.

Shared Humanity

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Re: The 2020/2021 freezing season
« Reply #1372 on: March 12, 2021, 02:26:07 PM »
Fram export tends to increase with this pattern.

Indeed it does! Here's the ECMWF Arctic cyclone forecast for midnight tonight UTC.

953 hPa over the Kara Sea accompanied by 970 hPa over the Bering Sea:

Jesus Christ! 953 hPa! This can't be normal in early March. Look at those isobars! Does this thing hang around for a while?

Freegrass

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Re: The 2020/2021 freezing season
« Reply #1373 on: March 12, 2021, 03:42:48 PM »
A comparison GIF of the ice on March 9 2020 and 2021.

Without an extreme weather event, I don't see us breaking any records this year with all that ice along the Siberian coast and in the Beaufort sea. Although the Atlantic side and Canadian coast does look worrying...

Click to play

The ESS will melt out completely. There will be little to no ice from the Chukchi to the Kara. Beaufort could hold out, especially if ice north of the CAA migrates to it which is usually the case.
The ESS will indeed most likely melt out completely. The question is how long it will take. If it melts out late, the sun will have less time, and less insolation left to heat up the water more north.

Last year the ESS and the Laptev had open water early on in the season. This helped to melt out more ice further north.

Thicker ice = later open water = less energy absorbed by the ocean = no record. One well placed storm could always change everything of course...

The same goes for the Beaufort. Last season, it just didn't want to melt out...

My concern is the Atlantic side. It's closer to the pole, where peak insolation is short. Early open water there could cause the pole to melt out.

Will we have a year where the only ice left is in the Beaufort? Nobody knows... But this set-up could get us there. Everything depends on the unpredictable weather now, as it always does...

WARNING!
Always take my analysis with a bucket of salt, as I am just an amateur with lots to learn.
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Niall Dollard

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Re: The 2020/2021 freezing season
« Reply #1374 on: March 12, 2021, 03:46:08 PM »

One thing they both agree on though is how little ice there is along the CAA.

The CAA covers a big area. I'm not sure where you are referring to FG.

Is it the furthest SW part off Banks Island or at the top of Ellesmere ? With persistent east winds blowing offshore from Banks, the ice can easily move away from the coast there.

But otherwise I thought, looking at those thickness charts, that many of the channels are not thin.

gerontocrat

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Re: The 2020/2021 freezing season
« Reply #1375 on: March 12, 2021, 04:52:12 PM »
The PIOMAS data (to 28 Feb) as supplied by Wipneus says that both Volume and thickness in the CAA has been extremely average in the freezing season this year.
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Freegrass

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Re: The 2020/2021 freezing season
« Reply #1376 on: March 12, 2021, 05:21:03 PM »

One thing they both agree on though is how little ice there is along the CAA.

The CAA covers a big area. I'm not sure where you are referring to FG.
I was actually referring to the ice all along the Canadian and Greenland coastline. Off of Ellesmere and the Lincoln sea, where usually the MYI ice gets stacked up to a thickness of multiple meters and the mega crack appears. The ice there is only around 2m thick now. I still don't know how to call that. When we say the Siberian coast, we all know that we're talking about the ESS and the Laptev. What do we call that on the other side? The North American Coastline (NAC)? The NAC Crack?  ::)
« Last Edit: March 12, 2021, 05:35:22 PM by Freegrass »
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Paul

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Re: The 2020/2021 freezing season
« Reply #1377 on: March 12, 2021, 06:32:05 PM »
Fram export tends to increase with this pattern.

Indeed it does! Here's the ECMWF Arctic cyclone forecast for midnight tonight UTC.

953 hPa over the Kara Sea accompanied by 970 hPa over the Bering Sea:

Jesus Christ! 953 hPa! This can't be normal in early March. Look at those isobars! Does this thing hang around for a while?

Quite a deep depression but I don't think out of the ordinary for March? Given how cold the air is under the low, it has virtually no affects on the ice apart from the ice in the ESS seperating from the fast ice.

Talking of fast ice, early indications suggest there is quite a bit more of it than there was last year and in general the Siberian regions do look healthier. Put it this way, be a major shock if the ice looked the way it did in May 2020 with all the polynas and general thinness which obviously meant a record retreat.

gerontocrat

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Re: The 2020/2021 freezing season
« Reply #1378 on: March 12, 2021, 06:33:25 PM »

One thing they both agree on though is how little ice there is along the CAA.

The CAA covers a big area. I'm not sure where you are referring to FG.
I was actually referring to the ice all along the Canadian and Greenland coastline. Off of Ellesmere and the Lincoln sea, where usually the MYI ice gets stacked up to a thickness of multiple meters and the mega crack appears. The ice there is only around 2m thick now. I still don't know how to call that. When we say the Siberian coast, we all know that we're talking about the ESS and the Laptev. What do we call that on the other side? The North American Coastline (NAC)? The NAC Crack?  ::)
That's an interesting question. Can't be the NAC as Greenland ain't the 51st State even if Trump did try to buy it. Given that Russia is East of the Greenwich meridian and the area from Alaska to NE Greenland is West of the Greenwich meridian I suppose the physical area is The Southern Ocean/Land Boundary of the Western Arctic Ocean but
- what a mouthful,
- noone would have a clue where that was.
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Niall Dollard

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Re: The 2020/2021 freezing season
« Reply #1379 on: March 12, 2021, 07:04:18 PM »
Gero Greenland is considered to be geographically part of North America.

So you could call it the North American Coastal Crack  ;D

Freegrass

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Re: The 2020/2021 freezing season
« Reply #1380 on: March 12, 2021, 07:24:04 PM »

One thing they both agree on though is how little ice there is along the CAA.

The CAA covers a big area. I'm not sure where you are referring to FG.
I was actually referring to the ice all along the Canadian and Greenland coastline. Off of Ellesmere and the Lincoln sea, where usually the MYI ice gets stacked up to a thickness of multiple meters and the mega crack appears. The ice there is only around 2m thick now. I still don't know how to call that. When we say the Siberian coast, we all know that we're talking about the ESS and the Laptev. What do we call that on the other side? The North American Coastline (NAC)? The NAC Crack?  ::)
That's an interesting question. Can't be the NAC as Greenland ain't the 51st State even if Trump did try to buy it. Given that Russia is East of the Greenwich meridian and the area from Alaska to NE Greenland is West of the Greenwich meridian I suppose the physical area is The Southern Ocean/Land Boundary of the Western Arctic Ocean but
- what a mouthful,
- noone would have a clue where that was.
Last year I came up with the CAAAGC... The sound a person makes when he gets crushed by two ice floes..  ::)

The Canadian Arctic Archipelago And Greenland Coast.
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Re: The 2020/2021 freezing season
« Reply #1381 on: March 12, 2021, 08:24:11 PM »
Certainly isn't much ice anywhere near the CAA, or north of Greenland. It's been withering out all the way from Fram to the Mackenzie delta down the shelf break zone on the edge of the deep ocean basin. Very little has survived even passing through the PGAS. Appalling to see it only start to skin over as it comes out the main channel into the Labrador. Only to be largely demolished by the warm flux from the Humboldt and Peterman basal discharge.
Even Elsemere Islands fiords have stubbornly refused to freeze over all winter. I assume that warm geofluid flux is passing under Nares in geological faults and porous strata, originating from the pressured Aquifer beneath Greenland and springing up to cause this.
The models appear to be thoroughly off the rails basin wide. Including Eosdis worldviews image processing which is based on only 500 to 1000m resolution anyway, but notorious for applying masks that show cohesive immobile ice where none actually is near coasts particularly.

[/quote]
I was actually referring to the ice all along the Canadian and Greenland coastline. Off of Ellesmere and the Lincoln sea, where usually the MYI ice gets stacked up to a thickness of multiple meters and the mega crack appears. The ice there is only around 2m thick now. I still don't know how to call that. When we say the Siberian coast, we all know that we're talking about the ESS and the Laptev. What do we call that on the other side? The North American Coastline (NAC)? The NAC Crack?  ::)
[/quote]

Glen Koehler

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Re: The 2020/2021 freezing season
« Reply #1382 on: March 12, 2021, 11:41:56 PM »
A comparison GIF of the ice on March 9 2020 and 2021.

An alternative comparison.

Click to enlarge/animate
    Both the CS2SMOS, and especially the HYCOM, models indicate that the centroid of ice thickness will be at a lower latitude heading into 2021 melt season than it was in 2020. 

    The relative solar radiation by latitude chart (originally from Tealight) suggests that a 10 deg. lower latitude shift from 80 to 70 would extend the length of melting season above a 7 watt/m2 threshold by about two weeks for both the start and end date.  Thus a total of 4 weeks.  But the shift is less than 10 degs., and losing the highest lat. degrees has less effect than lower ones, i.e. going from 80 to 75N has less impact than going from 75 to 70N. 

     If the center of the ice is 5 deg. farther to the south, that might represent an earlier shift for the start of melting season by about 4-5 days and delay the end date by 4-5 days, thus increasing melt season duration by about 8-10 days.  Adding a few days at the start and end when there is just barely enough solar energy to cause melt probably doesn't mean much.  But being at a lower latitude also means that solar radiation is more intense throughout melt season, so a 5 degs. southerly shift would be significant.

     This is just speculation piled on top of speculation, but to the extent to which any of this is valid, it suggests that while the 2020-2021 freezing season left the ASI in decent condition in terms of the metrics, when you factor in the positioning of the ice, things may be more precarious for the coming melt season than the Volume and Extent numbers by themselves indicate.
« Last Edit: March 13, 2021, 07:15:15 AM by Glen Koehler »

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Re: The 2020/2021 freezing season
« Reply #1383 on: March 13, 2021, 08:16:03 AM »
     This is just speculation piled on top of speculation, but to the extent to which any of this is valid, it suggests that while the 2020-2021 freezing season left the ASI in decent condition in terms of the metrics, when you factor in the positioning of the ice, things may be more precarious for the coming melt season than the Volume and Extent numbers by themselves indicate.

Very interesting thoughts Glen! Could even be true! :)

Iain

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Re: The 2020/2021 freezing season
« Reply #1384 on: March 13, 2021, 05:49:53 PM »
I checked back on Worldview. The ice bridge is further North West on the Parry channel, CAA than it has been for the time of year for the last 10 years.

There are also crack like features extending to the North and North West
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grixm

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Re: The 2020/2021 freezing season
« Reply #1385 on: March 13, 2021, 11:33:30 PM »
I checked back on Worldview. The ice bridge is further North West on the Parry channel, CAA than it has been for the time of year for the last 10 years.

There are also crack like features extending to the North and North West

In today's image there is also a new crack.

grixm

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Re: The 2020/2021 freezing season
« Reply #1386 on: March 13, 2021, 11:52:01 PM »
The south-west Okhotsk ice is going to have a rough time over the next few days. Temperatures will be above 0 for much of the ice extent, with not a lot of cloud cover to block the sun, either. And the ice is already in terrible shape: Many of the thicker floes are super dispersed, and the rest is only a thin gray layer that will likely melt away from this.

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Re: The 2020/2021 freezing season
« Reply #1387 on: March 14, 2021, 07:50:48 AM »
Let's go back to the ABC analysis to find out whether the extent maximum has already passed:

I evaluated the JAXA data of all freezing seasons from March 13 to the individual maximum to find out how often an increase of 0.16 M km² has happened after March 13. This is the value needed to be higher than the actual maximum from March 10 (14.24 M km²). I grouped these evaluations into the different decades. The evaluation has three outcomes:
A - an increase higher than 0.17 M km² has happened in x years (Pass), which means the maximum has not been reached
B - an increase of 0.16 ± 0.01 M km² has happened in y years (Intermediate), which means the maximum may have been reached, but maybe not
C - an increase of less than 0.15 M km² has happened in z years (Fail), which means the maximum has already been reached and we can start the melting season thread.

                     A       B      C
1979-1989:    0       2       9
1990-1999:    2       1       7
2000-2009:    0       2       8
2010-2020:    2       1       8
sum:              4       6     32

Summary: It is highly likely that we can declare March 10, 2021 as the date of this year's JAXA extent maximum. Another drop of more than 0.06 M km² tomorrow will put all "A" years into bin "B" and all "B" years into bin "C".
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oren

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Re: The 2020/2021 freezing season
« Reply #1388 on: March 14, 2021, 12:02:07 PM »
Thanks. Will evaluate again tomorrow, good chances of season switchover.

BornFromTheVoid

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Re: The 2020/2021 freezing season
« Reply #1389 on: March 14, 2021, 12:28:25 PM »
Slow animation for the last week. (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 #1390 on: March 14, 2021, 01:45:21 PM »
Thanks. Will evaluate again tomorrow, good chances of season switchover.

Yeah. It seems some insolation here, some winds there, and the AO now taking the expected dive are conspiring. Then there is the perhaps incidental conditions in the Parry Channel which is already more than 50% broken up...

I don't see the regrowth of 160k km sq.

The melt is on.

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Re: The 2020/2021 freezing season
« Reply #1391 on: March 14, 2021, 04:30:24 PM »
Latest Five Day Forecast
Wind + Temp @ Surface
Very Large GiF!

I've created this forecast with a larger overview so it includes the peripheral seas. That way it's easier to determine if we have reached the melting season yet. And we sure are close!

I think we'll be there in 2 or 3 days from now.
I think tomorrow is a good day to open the melting season thread.

I love to see the planet's "heartbeat" creeping back up again...
« Last Edit: March 14, 2021, 09:42:36 PM by Freegrass »
And so we pray...

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Re: The 2020/2021 freezing season
« Reply #1392 on: March 14, 2021, 06:55:36 PM »
High speed heat advection, March 18. Fasten belts!

oren

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Re: The 2020/2021 freezing season
« Reply #1393 on: March 15, 2021, 09:51:24 AM »
Following three days of extent losses, concentrated in "real" seas such as Bering, Barents and the Greenland Sea, rather than the marginally attached Okhotsk, and considering the relatively late date, we are now officially switching over to the 2021 melting season. Fasten your seat belts!

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Re: The 2020/2021 freezing season
« Reply #1394 on: March 15, 2021, 03:55:47 PM »
Following three days of extent losses, concentrated in "real" seas such as Bering, Barents and the Greenland Sea, rather than the marginally attached Okhotsk, and considering the relatively late date, we are now officially switching over to the 2021 melting season. Fasten your seat belts!

If you don't mind, I'll stick with my parachute.

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Re: The 2020/2021 freezing season
« Reply #1395 on: March 16, 2021, 03:20:04 PM »
Following three days of extent losses, concentrated in "real" seas such as Bering, Barents and the Greenland Sea, rather than the marginally attached Okhotsk, and considering the relatively late date, we are now officially switching over to the 2021 melting season. Fasten your seat belts!

If you don't mind, I'll stick with my parachute.
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gerontocrat

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Re: The 2020/2021 freezing season
« Reply #1396 on: March 16, 2021, 03:40:32 PM »
NSIDC Data - Sea Ice Area Graphs of the 2020-21 Freezing Season for each sea

I thought I would put the end of freezing season graphs in this thread. 14 seas so lots of posts.
This post... Total Area, Bering & Chukchi.
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gerontocrat

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Re: The 2020/2021 freezing season
« Reply #1397 on: March 16, 2021, 03:57:55 PM »
NSIDC Data - Sea Ice Area Graphs of the 2020-21 Freezing Season for each sea - continued

In this post...
Canadian Archipelago,
Hudson Bay,
Baffin Bay,
St. Lawrence.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: The 2020/2021 freezing season
« Reply #1398 on: March 16, 2021, 04:03:19 PM »
NSIDC Data - Sea Ice Area Graphs of the 2020-21 Freezing Season for each sea - continued

In this post...
Greenland,
Barents,
Kara,
Laptev.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: The 2020/2021 freezing season
« Reply #1399 on: March 16, 2021, 04:07:22 PM »
NSIDC Data - Sea Ice Area Graphs of the 2020-21 Freezing Season for each sea - continued

In this post...
The East Siberian Sea (ESS),
Beaufort,
Central Arctic,

and because it doesn't fit anywhere- The Okhotsk.

"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)