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Re: The 2020/2021 freezing season
« Reply #1000 on: January 08, 2021, 04:03:45 PM »
A rebound is a change in direction. To most that implies a sustained change. While their is not a precise definition in this case that would be a major increase in ice.  A minor uptick does not qualify. Their is a well established trend of decreasing ice with some yearly variation. Minor variations are not a rebound to most people even if your views are different.

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Re: The 2020/2021 freezing season
« Reply #1001 on: January 08, 2021, 04:38:39 PM »
Kara loses another 42k today ! It's claim to be a Central Arctic sea is becoming ever more questionable ..
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Re: The 2020/2021 freezing season
« Reply #1002 on: January 08, 2021, 05:05:59 PM »
I note Sea Ice Extent increases during the past week have been lethargic (Gerontocrat's graph).  Is there a described weather event causing this? Anything to do with the stratospheric sudden warming (SSW) event Gerontocrat described a couple days ago?  (If so, how?)
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Re: The 2020/2021 freezing season
« Reply #1003 on: January 08, 2021, 05:40:20 PM »
The sun will be coming up over the Kara fairly soon (~Jan. 21st).  Feebly at first, but by early February quite significantly (>6 hours of sunlight for 71N by February 10th).

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Re: The 2020/2021 freezing season
« Reply #1004 on: January 08, 2021, 07:06:39 PM »
I note Sea Ice Extent increases during the past week have been lethargic (Gerontocrat's graph).  Is there a described weather event causing this? Anything to do with the stratospheric sudden warming (SSW) event Gerontocrat described a couple days ago?  (If so, how?)
For some time there has been high presuure in the mid-Atlantic west of Eire.
Warmer moister weather has been pushing up into the Svalbard Barents / Kara areas causing sea ice extent and area losses instead of reaching the UK and NW Europe.

Looks like maybe next week normal service will be resumed?
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Re: The 2020/2021 freezing season
« Reply #1005 on: January 08, 2021, 08:46:31 PM »
A look at the rapid retreat/melt in the Kara sea in the last few days:

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Re: The 2020/2021 freezing season
« Reply #1006 on: January 08, 2021, 09:19:25 PM »
A rebound is a change in direction. To most that implies a sustained change. While their is not a precise definition in this case that would be a major increase in ice.  A minor uptick does not qualify. Their is a well established trend of decreasing ice with some yearly variation. Minor variations are not a rebound to most people even if your views are different.

In this case it is a matter of language. People, probably Neven or some early blogger, coined the term "rebound years" for relatively cold seasons 2013-2014 after the 2012 record, and 2008-2009 after 2007 (then, a record too).

The "melting" expectations generated by the record thin Arctic in early 2017 didn't verify, leading to a strong feeling of "rebound year". 2018 was not that warm either.

But I digress, probably off-topic, I agree with Oren that there is no so early indication on how the weather is going to come in summer.

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Re: The 2020/2021 freezing season
« Reply #1007 on: January 08, 2021, 09:53:02 PM »
A look at the rapid retreat/melt in the Kara sea in the last few days:

Thanks for this animation.  Looking at Aluminium's latest Bremen AMSR2 animation the ice cubes are sloshing around merrily in the glass throughout this whole Atlantic margin area -- from Svalbard to FJL to north of NZ.   It is not just the Kara Sea that is showing rapid losses in extent...
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Re: The 2020/2021 freezing season
« Reply #1008 on: January 09, 2021, 05:18:11 PM »
Kara ice loss impressive

Running out of time to freeze.

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Re: The 2020/2021 freezing season
« Reply #1009 on: January 09, 2021, 10:15:58 PM »
That's pretty wild to see such losses in JANUARY in the Kara. I'm very interested in following the entire 2021 season and I feel as though 2020's melt will be almost impossible to erase. Even the sea surface temp anomalies far north, and adjacent to the ice is "warm."

I will say, I'm quite surprised by the extremely persistent la niƱa pattern that's existed since at least last summer.

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Re: The 2020/2021 freezing season
« Reply #1010 on: January 10, 2021, 04:01:53 AM »
<Making a correction to a slightly misleading statement made on this thread, will post duplicate to 2020/2021 freezing season thread where it belongs better. Can be deleted from here after couple days as I assume people reading the thread will have noticed the correction put forward here.>

Incorrect. The peak winter cold is January 25, if not later. We are still definitely 3 weeks to 1 month away from annual peak winter cold based on annual averages. It is likely to be somewhat frozen soon. However, I drew attention to the Russian nuclear submariners and navy GCMs which I cited last summer who expect major mid-winter recirculation this year from around December 2021  that moves the typical storm tracks north of the British Isles to the latitude of Gibraltar with Pleistocene rains pouring in Sahara. This development is an ongoing: already this mid-winter now we can see it starting to take shape:
https://www.bbc.co.uk/news/world-europe-55586751 By end of 2021 it is multimillennial anomaly. If not right and next Christmas not delivering rainy Sahara, blame the Russians and their navy. ;) 

Kara ice loss impressive

Running out of time to freeze.
« Last Edit: January 10, 2021, 04:24:33 AM by VeliAlbertKallio »
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Re: The 2020/2021 freezing season
« Reply #1011 on: January 10, 2021, 10:25:37 AM »
Posts moved here where they belong, thank you VAK.

uniquorn

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Re: The 2020/2021 freezing season
« Reply #1012 on: January 10, 2021, 01:50:45 PM »
<Even the sea surface temp anomalies far north, and adjacent to the ice is "warm." >
Bering Sea ice perhaps reacting to that 'warmth' and persistent northerlies by building up an ice front rather than an ice edge. Could be cloud interference causing lower concentration further north though.
amsr2-uhh, bering, dec20-jan9 (click for movement)
https://go.nasa.gov/3orir0B  jan9

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Re: The 2020/2021 freezing season
« Reply #1013 on: January 10, 2021, 04:27:22 PM »
. However, I drew attention to the Russian nuclear submariners and navy GCMs which I cited last summer who expect major mid-winter recirculation this year from around December 2021  that moves the typical storm tracks north of the British Isles to the latitude of Gibraltar with Pleistocene rains pouring in Sahara.

VAK,

Yes you did write about these GCMs that predicted changed storm tracks but I never found any quotes  (by you or anyone else) to any studies that showed this. Can you point me to the right direction?

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Re: The 2020/2021 freezing season
« Reply #1014 on: January 11, 2021, 11:02:57 PM »
Another strong anticyclone i shaping up later this week.

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Re: The 2020/2021 freezing season
« Reply #1015 on: January 12, 2021, 07:02:20 AM »
What's going on in the upper atmosphere? The polar vortex is getting pushed aside...
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Re: The 2020/2021 freezing season
« Reply #1016 on: January 12, 2021, 09:46:42 AM »
What's going on in the upper atmosphere? The polar vortex is getting pushed aside...

Petition to rename it to "trans-Barents stream"?
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Re: The 2020/2021 freezing season
« Reply #1017 on: January 12, 2021, 09:46:50 AM »
<Please post only relevant stuff. O>
« Last Edit: January 12, 2021, 11:16:25 AM by oren »

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Re: The 2020/2021 freezing season
« Reply #1018 on: January 12, 2021, 12:26:13 PM »
amsr2-uhh comparison of 2021 with 2016 again, jan5-11, mercator surface temps inset for 2021. The warm West Spitzbergen current clearly winning at the moment.
Polarview S1B of the area north east of Svalbard this morning (UTC)
gnrt bathy of the same area. The round indent in the ice edge in 2021 sits over the turbulent waters above the entry (or exit) to the Yermak plateau dip

edit:Those indents look like they are more to do with the shelf break than the Yermak when overlaid.
« Last Edit: January 12, 2021, 07:59:35 PM by uniquorn »

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Re: The 2020/2021 freezing season
« Reply #1019 on: January 12, 2021, 01:47:39 PM »
What's going on in the upper atmosphere? The polar vortex is getting pushed aside...

A Sudden Stratospheric Warming event happened at the beginning of the year. Events like this may destroy the vortex for a while and/or displace it, thereby changing the direction of stratospheric winds and eventually messing with troposheric processes (eg beast from the east et al.). I posted about it in this thread at the end of last year and there are more posts about it in the atmospheric connections thread

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Re: The 2020/2021 freezing season
« Reply #1020 on: January 12, 2021, 02:08:26 PM »
Animation of the Barents and Kara Seas since December 20th.

Large file, click to play.
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Re: The 2020/2021 freezing season
« Reply #1021 on: January 13, 2021, 03:18:08 AM »
The AO was at historic lows below-3 on the 4th . Well I did find Jan. 1966 at -3.2 , Feb. 2010 -4.2 and Feb. 2020 also below -3 but those are the only numbers below -3 since 1950.

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/monthly.ao.index.b50.current.ascii.table

Also lots of warming at 30hPa

https://www.cpc.ncep.noaa.gov/products/intraseasonal/temp30anim.shtml
« Last Edit: January 13, 2021, 03:30:10 AM by Bruce Steele »

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Re: The 2020/2021 freezing season
« Reply #1022 on: January 13, 2021, 08:56:49 AM »
January 2-12.

2020.

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Re: The 2020/2021 freezing season
« Reply #1023 on: January 16, 2021, 06:20:09 PM »
Looking at old ice drift and thickness using a rough overlay of cs2smos onto ascat interferometry,  oct22-jan11
thickness scale is a guide due to overlay

Daylight over the Bering Sea  https://go.nasa.gov/38PbLnu
« Last Edit: January 17, 2021, 11:26:22 AM by uniquorn »

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Re: The 2020/2021 freezing season
« Reply #1024 on: January 17, 2021, 02:06:21 PM »
Slow animation for the week. Mostly subtle changes overall.
Click to play
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Re: The 2020/2021 freezing season
« Reply #1025 on: January 17, 2021, 02:14:17 PM »
Following up on the West Spitsbergen current, unfortunately the 2 argo floats in the current north east of Svalbard are now inactive. Here are the latest temperature and salinity charts for the 3 nearest floats to the west of Svalbard (from south to north)
SST is 4.8C close to the southern tip of Svalbard dropping to 3.4C further north.

KolĆ„s, E. and Fer, I.: Hydrography, transport and mixing of the West Spitsbergen Current: the Svalbard Branch in summer 2015, Ocean Sci., 14, 1603ā€“1618, https://doi.org/10.5194/os-14-1603-2018, 2018.
https://os.copernicus.org/articles/14/1603/2018/
Quote
Abstract

Measurements of ocean currents, stratification and microstructure were made in August 2015, northwest of Svalbard, downstream of the Atlantic inflow in Fram Strait in the Arctic Ocean. Observations in three sections are used to characterize the evolution of the West Spitsbergen Current (WSC) along a 170ā€‰km downstream distance. Two alternative calculations imply 1.5 to 2ā€‰Sv (1ā€‰Svā€‰=ā€‰106ā€‰m3ā€‰sāˆ’1) is routed to recirculation and Yermak branch in Fram Strait, whereas 0.6 to 1.3ā€‰Sv is carried by the Svalbard branch. The WSC cools at a rate of 0.20ā€‰āˆ˜C per 100ā€‰km, with associated bulk heat loss per along-path meter of (1.1āˆ’1.4)Ɨ107
ā€‰Wā€‰māˆ’1, corresponding to a surface heat loss of 380ā€“550ā€‰Wā€‰māˆ’2. The measured turbulent heat flux is too small to account for this cooling rate. Estimates using a plausible range of parameters suggest that the contribution of diffusion by eddies could be limited to one half of the observed heat loss. In addition to shear-driven mixing beneath the WSC core, we observe energetic convective mixing of an unstable bottom boundary layer on the slope, driven by Ekman advection of buoyant water across the slope. The estimated lateral buoyancy flux is O(10āˆ’8)ā€‰Wā€‰kgāˆ’1, sufficient to maintain a large fraction of the observed dissipation rates, and corresponds to a heat flux of approximately 40ā€‰Wā€‰māˆ’2. We conclude that ā€“ at least in summer ā€“ convectively driven bottom mixing followed by the detachment of the mixed fluid and its transfer into the ocean interior can lead to substantial cooling and freshening of the WSC.

AMSR2-UHH north of FJL struggling with weather related ice surface changes more than usual this year.
« Last Edit: January 17, 2021, 02:22:13 PM by uniquorn »

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Re: The 2020/2021 freezing season
« Reply #1026 on: January 18, 2021, 10:28:42 AM »
A closer look at surface features detected by amsr2-uhh, atlantic side, dec1-jan17. Ascat inset for drift comparison. Some correlation recently with the FYI/SYI white band discussed up thread.
« Last Edit: January 18, 2021, 11:36:51 AM by uniquorn »

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Re: The 2020/2021 freezing season
« Reply #1027 on: January 18, 2021, 04:34:16 PM »
How bad is the front in the CAB vs other years? It looks atrocious, it also looks like there was just a major surface melt event on the FYI that has migrated into the CAB as the MYI has exported through FRAM...

I am very nervous about the CAB situation as we head into spring. The sun will be coming up again soon, while we still have some time for freezing, it looks as though we may enter the melt season with the front further north than ever before in this region.

We have year over year HYCOM available in the same bandwidth. It appears we have avoided the same situation in 2019-20 (ice drifting off the Russian coast) but the outcome this year may be even worse to the overall sea ice as we have seen ice drifting into the Siberian coastline AND the Beaufort to the detriment of the CAB and ATL front in a very significant way.





My preliminary outlook for the melt season would be a very stout Beaufort that sees little melt. There is a major amount of MYI now in this area and it is quite thick. The Siberian Seas are also possibly going to melt more slowly than 2020. BUT, the situation in Kara is not really better, in fact it may be worse, and in the Barentz and CAB, it appears much worse. In fact, if there were a "look" that portended the Arctic pack splitting in two, this might be it.

I would assert with some confidence, the wind direction this year and the increase in wind speed over other years out of the ATL front (due to the warmer ATL? and warmer continents?) is now shunting ice growth increasingly to the periphery of the Arctic Ocean, instead of allowing ice to grow in its heart (the CAB). This has some benefit in that the CAB can build ice longer into spring than other regions due to its higher latitude / its insulation from heat intrusions thanks to peripheral seas being frozen -- but this year? The Barentz is still wide open and the Kara is almost the same or very thin besides the coastline, and the front is basically still in the CAB...

Perhaps we see a 2017, perhaps we see a new permutation on a catastrophic melt season a la 2012. With snowcover growth so far lackluster across the continents this winter season (to my surprise) and snow water equivalents also not so much above average, I think the sum of these factors favors a melt season more like 2012 than 2017 in terms of worsening sea ice vs. recovery. We are also still dealing with the rapid drop in aerosols that began in 2020 and has largely continued (though it may abate again in 2021-22).
« Last Edit: January 18, 2021, 04:43:14 PM by bbr2315 »

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Re: The 2020/2021 freezing season
« Reply #1028 on: January 18, 2021, 05:02:41 PM »
from NSIDC Data

There is usually a record breaker somewhere. The St Lawrence is at record low sea ice for the time of year both in Area (4 days) and in Extent (2 days).

Given that this sea is very much the smallest sea with the max sea ice extent in March well below 200 k in recent years, it will probably not be that significant is the wider scheme of things.
The St. Lawrence is significant because it feeds into the Gulf Stream (or rather, interacts with it). The HYCOM maps clearly show how much more saline and WARM the Northwest North Atlantic is this year vs. 2020. There is also a major snowfall deficit in southeast Quebec this year.

This may portend a much more vigorous push of warmth from the NW NATL into the CAB come spring and summertime, as the snowfall / snowmelt / cold airmasses that normally temper the sea surface temps in these regions are apparently largely absent this year, or at least, so far this winter.

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Re: The 2020/2021 freezing season
« Reply #1029 on: January 18, 2021, 09:40:41 PM »
How bad is the front in the CAB vs other years? It looks atrocious, it also looks like there was just a major surface melt event on the FYI that has migrated into the CAB as the MYI has exported through FRAM...

Not sure about major surface melt but there is some surface change. There are a couple of mosaic buoys recording ice surface temperature north of Svalbard. P156 and P157

amsr2-uhh, Atlantic side, jan17, 2013-2021

added SMOS/SMAP, Atlantic side, dec1-jan17. Almost certainly not surface melt.
« Last Edit: January 19, 2021, 12:06:40 PM by uniquorn »

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Re: The 2020/2021 freezing season
« Reply #1030 on: January 19, 2021, 01:38:54 AM »
So basically we have thicker ice on the Pacific side and thinner ice on the Atlantic side this year compared to last.  Overall, there does not appear to be a big difference.

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Re: The 2020/2021 freezing season
« Reply #1031 on: January 20, 2021, 11:13:52 AM »
So basically we have thicker ice on the Pacific side and thinner ice on the Atlantic side this year compared to last.  Overall, there does not appear to be a big difference.
Concur.

Overall, the damage to the refreeze has already been done.  We are now one month past the solstice, and the energy budget is rapidly moving away from building thick ice.

I am doubtful the peripheral seas will see much at all in the way of significant ice building.  The thickness numbers for the CAB and adjacent seas are sickening to look at. It is hard to imagine large stretches of the CAB being able to make it past 3M thickness.  If the polar vortex continues to be disrupted, we might be lucky to make it much past 2.5m for much of the pack.

I'm feeling rather pessimistic.
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Re: The 2020/2021 freezing season
« Reply #1032 on: January 20, 2021, 01:35:20 PM »
Has anyone noticed for the last few weeks how warm it is in Greenland, while Siberia looks extremely cold? Does anyone have the temperatures graphs for these places? Is Siberia colder than "normal"?

Here are some images that look extremely worrying to me... How abnormal is this? I always thought the cold would center more around the giant Greenland ice cube. But apparently something else is happening... Is this caused by La NiƱa? A warm Pacific? Or both?

A picture says more than a thousand words... So here are 3 from today.

https://earth.nullschool.net/#current/wind/isobaric/10hPa/overlay=temp/orthographic=-45.05,89.62,662
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Re: The 2020/2021 freezing season
« Reply #1033 on: January 20, 2021, 02:12:19 PM »
Grand solar minimum proponents are wetting themselves over the cold temperatures in siberia, while ignoring the warmth over greenland/ hudson bay.

I'm assuming this is the result of the SSW but would love to hear a clearer explanation.
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Re: The 2020/2021 freezing season
« Reply #1034 on: January 20, 2021, 02:55:07 PM »
Has anyone noticed for the last few weeks how warm it is in Greenland, while Siberia looks extremely cold? Does anyone have the temperatures graphs for these places? Is Siberia colder than "normal"?

Here are some images that look extremely worrying to me... How abnormal is this? I always thought the cold would center more around the giant Greenland ice cube. But apparently something else is happening... Is this caused by La NiƱa? A warm Pacific? Or both?

A picture says more than a thousand words... So here are 3 from today.

https://earth.nullschool.net/#current/wind/isobaric/10hPa/overlay=temp/orthographic=-45.05,89.62,662

Its certainly anomalously cold, and that looks set to persist
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Re: The 2020/2021 freezing season
« Reply #1035 on: January 21, 2021, 09:07:12 PM »
So basically we have thicker ice on the Pacific side and thinner ice on the Atlantic side this year compared to last.  Overall, there does not appear to be a big difference.
Concur.
Overall, the damage to the refreeze has already been done.  We are now one month past the solstice, and the energy budget is rapidly moving away from building thick ice.<>

The energy budget in the west spitsbergen current north east of Kvitoya is melting ice at the moment, shown here by a rammb animation (https://col.st/jkgLd), jan 20-21, 8.4MB. Some northerly winds are forecast in a couple of days, perhaps  the open water will close up a bit if the ice is thick enough on the CAB side.
If JayW is around perhaps he can confirm if this is also showing SST mixing

amsr2-uhh, atlantic side, jan1-20
polar view of part of the 'surface feature' area, jan16, 17 and 20. (10MB)


Quote
KvitĆøya (English: "White Island") is an island in the Svalbard archipelago in the Arctic Ocean, with an area of 682 square kilometres (263 sq mi). It is the easternmost part of the Kingdom of Norway. The closest Russian Arctic possession, Victoria Island, lies only 62 kilometres (39 mi) to the east of KvitĆøya.

The island is almost completely covered by KvitĆøyjĆøkulen, an ice cap with an area of 705 square kilometres (272 sq mi) with a classical, hourglass-shaped dome, which has given it its name. The few ice-free land areas are each only a few square kilometres large and very barren and rocky, the largest being AndrĆ©eneset on the southwest corner of the island. KvitĆøya is a part of the Nordaust-Svalbard Nature Reserve.

added latest early update from awi v103, jan20-21
« Last Edit: January 21, 2021, 11:05:37 PM by uniquorn »

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Re: The 2020/2021 freezing season
« Reply #1036 on: January 21, 2021, 11:03:06 PM »
So basically we have thicker ice on the Pacific side and thinner ice on the Atlantic side this year compared to last.  Overall, there does not appear to be a big difference.
Concur.

Overall, the damage to the refreeze has already been done.  We are now one month past the solstice, and the energy budget is rapidly moving away from building thick ice.

I am doubtful the peripheral seas will see much at all in the way of significant ice building.  The thickness numbers for the CAB and adjacent seas are sickening to look at. It is hard to imagine large stretches of the CAB being able to make it past 3M thickness.  If the polar vortex continues to be disrupted, we might be lucky to make it much past 2.5m for much of the pack.

I'm feeling rather pessimistic.

Thus far this year, the NSIDC extent moved from 1% below the average over the past decade to 1% above the decadal average. 

Niall Dollard

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Re: The 2020/2021 freezing season
« Reply #1037 on: January 23, 2021, 12:26:23 AM »
That patch well north of Svalbard (circa 85 N) is worryingly thin for that location at the end of January. I was wondering at first was it cloud or artefact related on the Bremen image but the PSL thickness chart picks it up as thin ice (blue colour - between 20cm and 30 cm).

Aluminium

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Re: The 2020/2021 freezing season
« Reply #1038 on: January 23, 2021, 05:23:44 AM »
January 11-21.

2020.

uniquorn

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Re: The 2020/2021 freezing season
« Reply #1039 on: January 23, 2021, 03:30:20 PM »
That patch well north of Svalbard (circa 85 N) is worryingly thin for that location at the end of January. I was wondering at first was it cloud or artefact related on the Bremen image but the PSL thickness chart picks it up as thin ice (blue colour - between 20cm and 30 cm).
It's possible that CS2SMOS is completely wrong in that area...

gerontocrat

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Re: The 2020/2021 freezing season
« Reply #1040 on: January 23, 2021, 04:01:59 PM »
That patch well north of Svalbard (circa 85 N) is worryingly thin for that location at the end of January. I was wondering at first was it cloud or artefact related on the Bremen image but the PSL thickness chart picks it up as thin ice (blue colour - between 20cm and 30 cm).

If nothing else even NSIDC's low-res sensor says there is a lot of low concentration ice in that area.
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uniquorn

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Re: The 2020/2021 freezing season
« Reply #1041 on: January 23, 2021, 04:34:41 PM »
smos/smap indicating that area is at least 50cm.
Nearest clearest day on worldview is jan17, https://go.nasa.gov/39VRADY
S1B from polarview showing a crop from 0-20E. Quite a lot of old leads (darker) and a sheared area of new leads or possibly new ridges (lighter, diagonally from top left).
The last image is default S1B sized crop of the sheared area showing open water leads as black between lighter lines. Probably a melange of refreeze and ridging.
« Last Edit: January 23, 2021, 05:21:52 PM by uniquorn »

BornFromTheVoid

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Re: The 2020/2021 freezing season
« Reply #1042 on: January 24, 2021, 02:03:06 PM »
Slow animation for the week. Click to play

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 #1043 on: January 25, 2021, 12:28:13 PM »
Overlay of polarview S1B onto amsr2-uhh, jan24. click for original scaled images. There is some correlation between darker S1B and lower concentration amsr2.
There are 4 good S1B's today to compare with tomorrow's amsr2.

Relatively clear over that area today on worldview, https://go.nasa.gov/3qNFAuX

Close up on 85N44-52E
« Last Edit: January 25, 2021, 01:25:24 PM by uniquorn »

BornFromTheVoid

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Re: The 2020/2021 freezing season
« Reply #1044 on: January 25, 2021, 05:25:03 PM »
A quick animation comparing extent across different years on January 24th
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 #1045 on: January 26, 2021, 01:07:29 PM »
Clearer weather north of Greenland saves us from attempting to interpret S1B images. Brightness temperature tends to show thicker ice as colder. Here we see the 'low concentration' areas identified by amsr2 correlating mostly with the thicker ice. These are clearly ice features, but at this time of year over the CAB, especially this year, they don't appear to represent sea ice concentration.

Overlay of amsr2(colours inverted) on to suomi/npp viirs brightness temperature(band15), jan25/26
https://go.nasa.gov.3sWLTOH

amsr2-uhh atlantic side, dec1-jan25
« Last Edit: January 26, 2021, 03:06:41 PM by uniquorn »

uniquorn

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Re: The 2020/2021 freezing season
« Reply #1046 on: January 26, 2021, 01:12:32 PM »
A quick animation comparing extent across different years on January 24th
The Sea of Okhotsk racing away this year with those cold northerly winds.

amsr2-uhh, dec1-jan25

amsr2 3.125km extent (wipneus' data)
« Last Edit: January 26, 2021, 03:06:58 PM by uniquorn »

SimonF92

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Re: The 2020/2021 freezing season
« Reply #1047 on: January 26, 2021, 04:58:02 PM »
Great figures as always both of you, thanks for keeping us up to date with unique content
Bunch of small python Arctic Apps:
https://github.com/SimonF92/Arctic

nadir

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Re: The 2020/2021 freezing season
« Reply #1048 on: January 26, 2021, 08:07:53 PM »
The 144h of EC 12h forecast (Feb 1) predicts an amazing pressure gradient across the basin driven by a 1061 hPa high

Will February bring some Cracks of Doom?

charles_oil

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Re: The 2020/2021 freezing season
« Reply #1049 on: January 26, 2021, 11:41:30 PM »
seconded !


I think BornFTV has a 2020 caption on what I assume is this year's 2021 graphic ....... 


Thanks again.