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Author Topic: The 2020/2021 freezing season  (Read 176616 times)

sailor

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Re: The 2020/2021 freezing season
« Reply #900 on: December 10, 2020, 02:22:07 PM »
Large Arctic anticyclone is forecast to intensify and build over the Pole over the coming week.

Under its dome, temperatures are expected to dip below -30 C. This is roughly in the area that contributes most to the DMI N80 mean temperature.

That in itself should be nothing new. However in the last quarter of recent years it has been very rare for the DMI N80 graph to dip below the green 1958-2002 green line. Have to go back to 2015 to get below briefly.

If the forecast holds true, it is possible it may dip below by Dec 16th.

Regardless of the heat loss at surface level, this very strong anticyclone is associated to a warming of the entire polar troposphere disrupting the pole circulation.

The european model forecast for one week is very revealing with z500 altitude anomalies locked at the pole, and values typical of spring or even summer.

The max pressure that may reach well over 1060 Hpa !

Is all this craze related to the SSW that was told might be happening about now? And what could we expect of this freak event?

El Cid

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Re: The 2020/2021 freezing season
« Reply #901 on: December 10, 2020, 02:42:14 PM »

Is all this craze related to the SSW that was told might be happening about now? And what could we expect of this freak event?

No serious SSW (and vortex split) can currently be seen in the 10-15 day forecasts

sailor

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Re: The 2020/2021 freezing season
« Reply #902 on: December 10, 2020, 03:30:53 PM »

Is all this craze related to the SSW that was told might be happening about now? And what could we expect of this freak event?

No serious SSW (and vortex split) can currently be seen in the 10-15 day forecasts
My mistake then. Thought I had read something on Twitter but I don’t know much about this.

Nonetheless can we call the prediction WACCy? (At all atmosphere levels except near the surface obviously)

BornFromTheVoid

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Re: The 2020/2021 freezing season
« Reply #903 on: December 10, 2020, 04:42:36 PM »
Without a substantial increase in extent on tomorrows update, looks like we'll be back to lowest on record.
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

romett1

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Re: The 2020/2021 freezing season
« Reply #904 on: December 10, 2020, 11:04:14 PM »
Without a substantial increase in extent on tomorrows update, looks like we'll be back to lowest on record.
Main reason seems to be the area east to Novaya Zemlya - Dec 9, 2020 vs Dec 9, 2019.
Models are still showing sea surface temperatures to be above 0 °C in some parts of the Kara Sea on Dec 19.


Comradez

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Re: The 2020/2021 freezing season
« Reply #905 on: December 11, 2020, 12:19:20 AM »
Looks like the southern Kara Sea might have some serious trouble freezing over solid at all this winter.  Water temperature still around 2C.  A month from now, the sun will be coming back up, although it won't be until the beginning of February before any significant insolation will reach the southern Kara.  If there is still open water, or even open leads, by then then that will seriously impact next year's melt there. 

BornFromTheVoid

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Re: The 2020/2021 freezing season
« Reply #906 on: December 11, 2020, 04:41:09 PM »
Ice growth so far this refreeze, at increments of 10 days.
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

El Cid

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Re: The 2020/2021 freezing season
« Reply #907 on: December 12, 2020, 10:15:03 AM »
Now we seem to have a relatively minor SSW at day 9 on the GFS (I drew a green line to show where the warming happens and a red line to show the displacement). It does not lead to a vortex split though, only to a small displacement. This will likely not have a major effect on NH weather. We would need to see a vortex split to see some real action (as in Beast from the East snowstorms, etc)

Pagophilus

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Re: The 2020/2021 freezing season
« Reply #908 on: December 12, 2020, 03:37:43 PM »
Looks like the southern Kara Sea might have some serious trouble freezing over solid at all this winter.  Water temperature still around 2C.  A month from now, the sun will be coming back up, although it won't be until the beginning of February before any significant insolation will reach the southern Kara.  If there is still open water, or even open leads, by then then that will seriously impact next year's melt there.

<some later edits as I looked over more data>  I think there is a good chance the Southern Kara will freeze over completely.  Looking over previous years via the NSIDC comparison tool, Dec 2012 and Dec 2016 both had substantial portions of the South Kara Sea unfrozen as of Dec 11.  There was not quite as much open water as there is this year, but close.  Portions of the South Kara remained open water in both these years during the following January (2013, 2017), but the South Kara Sea was then completely frozen over in February, March, April and May, only beginning to melt out in June. 

That said, there is one notable exception.  The only year I could find that the South Kara had some small areas of open water throughout the winter and spring was over the freezing season of 2011/2012.  And we all know what happened in the fall of 2012.   Oddly enough, even though there was largely open water in February 2012 in the South Kara, it still mostly froze over in the late spring (April, May).     

I understand the argument of the renewal of insolation in February, but the days then are short and the angle of insolation is very low.  Ice extent was still increasing during February and March in the general area of the Kara in the above years (2013, 2017), and in other years (including that late spring freeze in 2012).  So I would be surprised if the South Kara, despite its current surface temperatures, did not freeze over completely at some point this winter, unless winter is defined as just December and January.  It could happen that it does not completely freeze over, however, and that would be an ominous indicator for the fall of 2021. 
« Last Edit: December 13, 2020, 03:48:14 PM by Pagophilus »
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oren

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Re: The 2020/2021 freezing season
« Reply #909 on: December 12, 2020, 06:08:09 PM »
Indeed, Kara has the most ice in Feb and Mar, and it should freeze over this year as well. The problem is the thickness (or lack thereof). The later it freezes over, the thinner the resulting ice.

Bruce Steele

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Re: The 2020/2021 freezing season
« Reply #910 on: December 12, 2020, 09:54:03 PM »
Bornfromthevoid, Does the SSW in El Cids post above have something to do with your checklist ?

https://www.netweather.tv/weather-forecasts/news/10610-arctic-amplification-and-winter-weather---whats-the-connection


John Batteen

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Re: The 2020/2021 freezing season
« Reply #911 on: December 13, 2020, 02:52:25 AM »
That said, there is one notable exception.  The only year I could find that the South Kara had some small areas of open water throughout the winter and spring was over the freezing season of 2011/2012.  And we all know what happened in the fall of 2012.   Oddly enough, even though there was largely open water in February 2012 in the South Kara, it still mostly froze over in the late spring (April, May).

It's interesting you say this because I have been drawing other parallels to winter 11/12 in midlatitude weather.  The on the ground experience in SD/MN has been very similar thus far.  Well above average temps, lots of sunshine, very little snow, in a la nina year which typically brings the opposite.  Can anyone else who knows more about this stuff than I do see if these years are really as similar as they seem with regard to global atmospheric setup?

Aluminium

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Re: The 2020/2021 freezing season
« Reply #912 on: December 13, 2020, 08:07:28 AM »
November 22 - December 12.

2019.

uniquorn

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Re: The 2020/2021 freezing season
« Reply #913 on: December 13, 2020, 01:55:08 PM »
Turbulence over the Nansen Basin shelf break north of FJL/Svalbard.
Rammb slider https://col.st/8XUJA (8MB)
imagej contrast max141, clahe2.3, add30

oren

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Re: The 2020/2021 freezing season
« Reply #914 on: December 13, 2020, 02:15:05 PM »
November 22 - December 12.

2019.
Wow, the southern Kara and the region east of FJL are in seriously bad shape. OTOH the Chukchi has finally found some nice growth, hopefully the weather will not turn before the new ice manages to stabilize.

Shared Humanity

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Re: The 2020/2021 freezing season
« Reply #915 on: December 13, 2020, 03:12:36 PM »
Laptev is also freezing up nicely now. Less movement of the ice along the shoreline.

BornFromTheVoid

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Re: The 2020/2021 freezing season
« Reply #916 on: December 13, 2020, 05:16:23 PM »
Weekly animation. The Chukchi Sea is quickly filling in and the Bering Sea gained its first substantial ice cover. Growth is slow in most areas, however. Kara is still struggling to gain any ice and continues lowest on record.
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

uniquorn

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Re: The 2020/2021 freezing season
« Reply #917 on: December 13, 2020, 06:11:16 PM »
<>The Chukchi Sea is quickly filling in<>
Yes. High winds helping to spread the ice eastwards from the Beaufort. Over 100km/h 1000hPa today according to nullschool.
rammb, chukchi, https://col.st/0bPR8   (7MB click) Utqiagvik lower right.
added amsr2-uhh, dec1-12
« Last Edit: December 13, 2020, 11:35:23 PM by uniquorn »

uniquorn

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Re: The 2020/2021 freezing season
« Reply #918 on: December 14, 2020, 12:31:52 AM »
A closer look (750m resolution) at the Chukchi ice edge. Wind blown ice drifting over warm(ish) water. Smaller floes disappearing as they cool the ocean. 1000hPa winds translating to roughly 80km surface winds forecast again for much of tomorrow.
rammb https://col.st/b7feS
stationary frames have been left in to maintain the flow of time,  72% scale to reduce to 6.3MB
further coverage to Wrangel island here


edit: surface winds were a bit lower today than forecast ~70km/h (~90km/h at 1000hPa)
« Last Edit: December 14, 2020, 12:03:12 PM by uniquorn »

interstitial

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Re: The 2020/2021 freezing season
« Reply #919 on: December 14, 2020, 01:33:15 AM »
That said, there is one notable exception.  The only year I could find that the South Kara had some small areas of open water throughout the winter and spring was over the freezing season of 2011/2012.  And we all know what happened in the fall of 2012.   Oddly enough, even though there was largely open water in February 2012 in the South Kara, it still mostly froze over in the late spring (April, May).

It's interesting you say this because I have been drawing other parallels to winter 11/12 in midlatitude weather.  The on the ground experience in SD/MN has been very similar thus far.  Well above average temps, lots of sunshine, very little snow, in a la nina year which typically brings the opposite.  Can anyone else who knows more about this stuff than I do see if these years are really as similar as they seem with regard to global atmospheric setup?
don't forget el Nino la Nina is based on a rolling ten year average. Current conditions will be judged almost entirely on a warmer ocean then 2011/12. While the ocean is only warming about 0.1 degrees Celsius a decade it can make a difference.

Freegrass

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Re: The 2020/2021 freezing season
« Reply #920 on: December 14, 2020, 12:33:40 PM »
The last of the thick MYI has now completely moved into the beaufort, and the wind pattern for the coming week will surely speed that up...
And so we pray...

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uniquorn

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Re: The 2020/2021 freezing season
« Reply #921 on: December 14, 2020, 12:57:27 PM »
That (modelled) thick ice mostly over shallower water.

whoi itp121, currently making it's way along the shelf break, is going through another wave of over 2C water at ~50m.
itp120 meanwhile is just nearing itp121's deployment location.

It looks like the mixing layer has mostly gone. I've no diving experience but it must be interesting at the interface of those two layers at the moment.
Quote
year   day     pressure   temp(C)  salinity
2020  349.03395   40    1.0757   30.0039
2020  349.03383   42    1.7192   30.3061
2020  349.03372   44    2.0106   30.4878
2020  349.03361   46    2.1042   30.5943
2020  349.03351   48    2.0493   30.7095
2020  349.03340   50    2.0160   30.8157
2020  349.03331   52    2.0032   30.8900
2020  349.03322   54    1.8781   30.9629
2020  349.03313   56    1.7315   31.0375
2020  349.03303   58    1.6991   31.0938
2020  349.03293   60    1.4741   31.1858
Titles abbreviated to match columns

Areas coloured white are above 1.8C (out of expected scale)
« Last Edit: December 14, 2020, 04:47:53 PM by uniquorn »

SimonF92

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Re: The 2020/2021 freezing season
« Reply #922 on: December 14, 2020, 01:04:22 PM »
I cant post images on uni vpn for some reason, but Cryosat SAR completely disagrees about the current state of thickness and where the thick ice is

http://www.cpom.ucl.ac.uk/csopr/seaice.php

(Select '2-Days' not '28-Days')
Bunch of small python Arctic Apps:
https://github.com/SimonF92/Arctic

Freegrass

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Re: The 2020/2021 freezing season
« Reply #923 on: December 14, 2020, 02:08:56 PM »
Is it possible that the model is missing that bottom heat thinning the ice, hence a different outcome when measured?
And so we pray...

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uniquorn

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Re: The 2020/2021 freezing season
« Reply #924 on: December 14, 2020, 03:35:19 PM »
CS2SMOS merged thickness from AWI netcdf via panoply. click for ani(5.7MB)

Cryosat SAR click for 14day and 2day

« Last Edit: December 14, 2020, 04:42:45 PM by uniquorn »

uniquorn

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Re: The 2020/2021 freezing season
« Reply #925 on: December 15, 2020, 12:49:25 AM »
A touch of refreeze coming to the eastern Novaya Zemlya coast. The St Anna trough making it's presence felt.
amsr2 awi v103, dec6-14(early)
gebco undersea features gazetteer
« Last Edit: December 15, 2020, 12:54:48 AM by uniquorn »

BornFromTheVoid

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Re: The 2020/2021 freezing season
« Reply #926 on: December 15, 2020, 11:00:30 AM »
A closer look (750m resolution) at the Chukchi ice edge. Wind blown ice drifting over warm(ish) water. Smaller floes disappearing as they cool the ocean. 1000hPa winds translating to roughly 80km surface winds forecast again for much of tomorrow.
rammb https://col.st/b7feS
stationary frames have been left in to maintain the flow of time,  72% scale to reduce to 6.3MB
further coverage to Wrangel island here


edit: surface winds were a bit lower today than forecast ~70km/h (~90km/h at 1000hPa)

Here's an update with the Bremen concentration. Starting to eat into the ESS coverage now too.

I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

El Cid

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Re: The 2020/2021 freezing season
« Reply #927 on: December 18, 2020, 08:37:53 AM »
That Sudden Stratospheric Warming is likely coming soon. Every run of GFS in the past few days had some variation of it and although it is really far out (10+ days ), so we can not be certain, but the consistency of bringing it up every time is interesting. We will be more sure of it in a week but I just wanted to attach 2 pictures, how GFS has us from having a polar vortex and then hardly having it (only in a very deformed, weakened state):

mdoliner

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Re: The 2020/2021 freezing season
« Reply #928 on: December 19, 2020, 04:46:05 PM »
Does anyone make anything of the fact that the years with the highest maximums in March have the lowest minimums in September, at least for the last four or five years. Perhaps large ice covers make for good melt pond weather.

Aluminium

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Re: The 2020/2021 freezing season
« Reply #929 on: December 20, 2020, 10:49:29 AM »
December 10-19.

2019.

sailor

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Re: The 2020/2021 freezing season
« Reply #930 on: December 20, 2020, 03:47:50 PM »
First interesting news of the freezing season.

JAXA, December 18, 2020

Extent: 11,562444 km2
Gain of 144,467 km2

5th lowest in the satellite record. Could only last a day. Could move down to 6th.

2016:  11,295,762 km2
2017:  11,546,507 km2
2019:  11,553,665 km2
2010:  11,548,406 km2
2020:  11,562,444 km2
2018:  11,564,084 km2

<FTB, haven't seen you in a while, it seems tendency for cherrypicking has remained. Am approving this post on a one-time basis but will not tolerate on an ongoing basis. O>

Aluminium’s animation shows that the prevailing winds bringing coldness from Alaska and inducing very strong ice drift over the Chukchi sea explain the recent increases in extent (mostly)

The guys at MOSAIC thread are documenting what’s going on with the anticyclonic drift basin-wide very nicely. Go have a look.

Also the strong high pressure dome has displaced cold air to the periphery in particular to Kara, that was late in refreeze and is quickly picking up.

If you find this event the first interesting news from the freezing season, you have not been following or you are quite ill intentioned as oren suggests.

uniquorn

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Re: The 2020/2021 freezing season
« Reply #931 on: December 21, 2020, 09:44:47 PM »
The last of the thick MYI has now completely moved into the beaufort, and the wind pattern for the coming week will surely speed that up...
Ascat tending to confirm that hycom forecast, day297-355.
crf 27 compression, 1.2MB

Niall Dollard

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Re: The 2020/2021 freezing season
« Reply #932 on: December 21, 2020, 11:42:05 PM »
Quite the drop in temperature at Dikson, on the Russian coast of the Kara Sea during this month.

Considering three of the first 4 days of December set record maxima. 

El Cid

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Re: The 2020/2021 freezing season
« Reply #933 on: December 22, 2020, 12:02:34 PM »
Quite the drop in temperature at Dikson, on the Russian coast of the Kara Sea during this month.

Considering three of the first 4 days of December set record maxima.

Well, that should not be much of a surprise. No (or only very thin) ice (beginning of DEC) = open seas= warmth. Ice (now)= no help from oceanic heat= cold.

Pagophilus

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Re: The 2020/2021 freezing season
« Reply #934 on: December 22, 2020, 05:14:13 PM »
Does anyone make anything of the fact that the years with the highest maximums in March have the lowest minimums in September, at least for the last four or five years. Perhaps large ice covers make for good melt pond weather.
Much extent growth from now on takes place in the peripheral seas (Okhotsk, Bering, Greenland etc).  So, IMO, those extent maxima for each year, while they are accurate, reflect a very broad situation.   Most of the peripheral seas extent tends to melt out relatively quickly each year, and it is after that when the total-extent-based-picture becomes a clearer indication of the health of the Central Arctic icepack itself.  I am not saying the freezing of the peripheral seas is not significant, but their condition in March is not a great indicator of where the central ice pack will be in September.
« Last Edit: December 22, 2020, 05:19:51 PM by Pagophilus »
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grixm

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Re: The 2020/2021 freezing season
« Reply #935 on: December 22, 2020, 07:06:31 PM »
Look at that clean and uniform rotation

Niall Dollard

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Re: The 2020/2021 freezing season
« Reply #936 on: December 23, 2020, 12:06:59 AM »
Quite the drop in temperature at Dikson, on the Russian coast of the Kara Sea during this month.

Considering three of the first 4 days of December set record maxima.

Well, that should not be much of a surprise. No (or only very thin) ice (beginning of DEC) = open seas= warmth. Ice (now)= no help from oceanic heat= cold.

The location of Dikson with relatively warm Kara Sea located to its north and west and with occasional southwest winds advecting warm air from western Europe means that for deep cold at this time of year, they really need winds with an easterly component and that's just what they got from the 6th December

I think the warmer temperatures were more to do with the warm seas allowing more cyclonic activity in the Barents and into the Kara preventing it from a more rapid freeze and giving winds with a more westerly component.

When finally the synoptic pattern change, winds instead advected air from the interior of Russia.

Why the cyclonic influence persisted for so long this year at Dikson is likely related to the almost complete absence of ice on the Russian side of the Arctic this summer.

   

El Cid

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Re: The 2020/2021 freezing season
« Reply #937 on: December 23, 2020, 08:40:54 AM »
RE:Dickson (and Siberian Islands) high temps during autumn, early winter

I think we have a new pattern here (my pet theory). With the Siberian seas melting early, then warming up and accumulating huge amounts of heat during summer, they can not freeze until Nov/Dec. The huge open seas are very much warmer than surrounding landmasses, so cold pours into this "warm gap" , warms up and rises, creating a huge low pressure system. I think that in the future there will be an 'Arctic Low" instead of the classical Icelandic Low due to this. (I theorized about this before, but this year) we finally saw this happening during October/November. This low creates wind patterns that "protect" Dickson. See schematic picture...

My conclusion: this will likely be a regular feature in the following years

Niall Dollard

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Re: The 2020/2021 freezing season
« Reply #938 on: December 23, 2020, 10:33:09 AM »
This weather pattern was also prevalent in the late 1930s. Dikson managed to record above zero C temperatures in mid December 1938.

Not saying that the summer extent was as low as this year, but Kara was very slow to freeze up that autumn.

El Cid

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Re: The 2020/2021 freezing season
« Reply #939 on: December 23, 2020, 11:40:12 AM »
Niall, where do you find ice charts for the 1930s?

colding

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Re: The 2020/2021 freezing season
« Reply #940 on: December 23, 2020, 11:45:30 AM »
You can find ice charts going back to the 1800's here:

http://brunnur.vedur.is/pub/trausti/Iskort/Pdf/

Freegrass

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Re: The 2020/2021 freezing season
« Reply #941 on: December 23, 2020, 02:39:36 PM »
The last of the thick MYI has now completely moved into the beaufort, and the wind pattern for the coming week will surely speed that up...
Ascat tending to confirm that hycom forecast, day297-355.
crf 27 compression, 1.2MB
Awesome animation Uniquorn! Can we conclude that Hycom captures the movement of the ice quite accurately? How about thickness?
And so we pray...

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Freegrass

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Re: The 2020/2021 freezing season
« Reply #942 on: December 23, 2020, 02:59:58 PM »
Latest Five Day Forecast + Last 48 Hours
Wind + Temp @ Surface
Very Large GiF!

Interesting weather pattern developing. The December 2020 GAAC is turning into a completely different monster for the ice...
And so we pray...

When factual science is in conflict with our beliefs, we cuddle up in our own delusional fantasy where everything starts making sense again...

uniquorn

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Re: The 2020/2021 freezing season
« Reply #943 on: December 23, 2020, 11:30:12 PM »
The last of the thick MYI has now completely moved into the beaufort, and the wind pattern for the coming week will surely speed that up...
Ascat tending to confirm that hycom forecast, day297-355.
crf 27 compression, 1.2MB
Awesome animation Uniquorn! Can we conclude that Hycom captures the movement of the ice quite accurately? How about thickness?
I'll stick with 'tending to confirm' Hycom modelling of north CAA coastal ice movement during day297-355 2020.

Freegrass

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Re: The 2020/2021 freezing season
« Reply #944 on: December 24, 2020, 01:20:14 AM »
Look what you did Unicorn. You made it angry!
I'll stick with not completely useless tool.
And so we pray...

When factual science is in conflict with our beliefs, we cuddle up in our own delusional fantasy where everything starts making sense again...

uniquorn

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Re: The 2020/2021 freezing season
« Reply #945 on: December 24, 2020, 01:53:48 PM »
CS2SMOS merged SIT oct16-22 to dec14-20. An attempt at measurement rather than modelling.
« Last Edit: December 24, 2020, 01:59:08 PM by uniquorn »

A-Team

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Re: The 2020/2021 freezing season
« Reply #946 on: December 25, 2020, 12:46:43 AM »
The mp4 below shows 84 days of the fall freeze season, from Oct 01 to Dec 23. Here SMOS was used at 132.24% enlargement to provide masks for land, open water and thin ice as Ascat alone has distracting artifacts there especially early in the season.

Note a white band of ice (an extended virtual buoy for tracking purposes) forms early on in the northern Laptev at the FYI/SYI edge (as it did last year) and will likely remain trackable until May. The overall pattern of ice movement here has been a squash towards Greenland and the CAA.

The physical explanation for the hundreds of km of white band remains elusive. Efficient scattering from low dielectric near-surface ice is typically seen in older ice that has lost its brine pockets. However Ascat's active microwave beam can also be reflected back from crumpled ice with right-sized debris particles. How and why this would form at the edge of SYI perhaps may require strong 'offshore' winds piling up newly formed ice. The area is inaccessible to ships and the feature may not be apparent at visible or infrared wavelengths anyway.

Other stably advecting Ascat features such the large dark elongated patch in the north Beaufort also lack interpretation. This area froze up very rapidly in patches per Smos-Smap and so may have incorporated extra near-surface salinity which would indeed make it appear darker.

Note too the unusual mid-December surge of ice west across the Chukchi to the shores of Chukotka; usually western Alaskan ice originating northeast of Banks Island turns north upon reaching the eastern Chukchi, perhaps riding Bering Strait inflows.

This can be attributed to the persistent anti-cyclone over the period 08-24 Dec 2020 that has brought clear skies and with it excellent Suomi band 15 views of heat loss from leads and their motion (https://go.nasa.gov/2KPeWlH opens to a good palette set-up). As the large diameter anti-cyclone wandered across the Arctic Ocean towards the Kara side, winds often blew in the opposite direction of that needed for a return Gyre.

Export out the Fram has picked up but has the odd oblique meridional surge is from the central CAB rather than the usual zonal route between the pole and the SZ-FJL-Svalbard. This could have the effect of exporting older thicker ice but this year, as witnessed by the Polarstern, the ice between Greenland and the pole did not fit that description in September.
« Last Edit: December 25, 2020, 08:53:59 PM by A-Team »

uniquorn

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Re: The 2020/2021 freezing season
« Reply #947 on: December 26, 2020, 01:53:42 PM »
Quote
Note a white band of ice (an extended virtual buoy for tracking purposes) forms early on in the northern Laptev at the FYI/SYI edge (as it did last year) and will likely remain trackable until May.
A closer look at part of the white band today using Polarview S1B. It could be widespread ridging, maybe the old ice edge also has higher surface salinity due to a longer period with waves washing over it.

ascat white bands since 2010
« Last Edit: December 26, 2020, 02:23:53 PM by uniquorn »

uniquorn

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Re: The 2020/2021 freezing season
« Reply #948 on: December 26, 2020, 08:19:10 PM »
An attempt to identify the white band in worldview by overlaying S1B onto a very enlarged ascat and suomi npp viirs brightness temperature band15 night. All from dec14, the nearest clear(ish) day.

Also an overlay of dec26 S1B onto dec14 at 50% transparent.

On a different note, the Atlantic front is still very sensitive to wind direction.
amsr2 awi v103 dec18-26(early)

Mosaic floe2 at ~87N also reacting to yesterday's 50km/h southerlies.
« Last Edit: December 26, 2020, 10:26:32 PM by uniquorn »

Freegrass

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Re: The 2020/2021 freezing season
« Reply #949 on: December 27, 2020, 05:02:23 AM »
Quote
Note a white band of ice (an extended virtual buoy for tracking purposes) forms early on in the northern Laptev at the FYI/SYI edge (as it did last year) and will likely remain trackable until May.
A closer look at part of the white band today using Polarview S1B. It could be widespread ridging, maybe the old ice edge also has higher surface salinity due to a longer period with waves washing over it.

ascat white bands since 2010
It's common in nature that annual boundaries become visual. Think of rings in trees, and coral, etc...

It's just a boundary between two different kinds of ice... The ice that was, and the ice that became...

Old and new... Just like trees...

Edit:
But I would go with waves as well for the possible culprit. Boundaries are subjected to a whole lot of forces that the inner ice isn't...
« Last Edit: December 27, 2020, 05:11:59 AM by Freegrass »
And so we pray...

When factual science is in conflict with our beliefs, we cuddle up in our own delusional fantasy where everything starts making sense again...