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SimonF92

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Re: The 2020/2021 freezing season
« Reply #700 on: November 03, 2020, 07:08:45 PM »
Slowly working my way through retroactively visualising all the buoys in one go (last 21 days of data)

Some of these sensors are in air and some are not, still need to separate that out.

I also need to generate bounding longitudes for each of the seas to better separate the data as right now it is far too busy- there are 101 currently reporting buoys north of 70N
Bunch of small python Arctic Apps:
https://github.com/SimonF92/Arctic

gandul

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Re: The 2020/2021 freezing season
« Reply #701 on: November 03, 2020, 07:19:04 PM »
Quite a spectacle to see landfast coastal ice reach the main pack expansion at hundreds of km of distance.

romett1

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Re: The 2020/2021 freezing season
« Reply #702 on: November 03, 2020, 07:37:30 PM »
ESS, Laptev between Oct 30 and Nov 2 and 7-day outlook. Sea surface temp forecast for Nov 12 also added, seems like it takes some time until Laptev freezes over.

gandul

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Re: The 2020/2021 freezing season
« Reply #703 on: November 03, 2020, 08:17:24 PM »
The disruption of the polar circulation, again, is not however going to perpetuate open ocean anymore. ESS really cold, but I believe Laptev too might be closed by mid November. No chance to see a dragon until next year.

romett1

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Re: The 2020/2021 freezing season
« Reply #704 on: November 03, 2020, 09:02:23 PM »
There is lot of warmth on the way from the Atlantic towards Laptev between Nov 11 and Nov 13. Still far away but worth to look at.

Pagophilus

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Re: The 2020/2021 freezing season
« Reply #705 on: November 03, 2020, 10:21:01 PM »
Nope, definitely the Mpemba effect  ::)

Well, that lead to me using up 15 mins of my life that I will never get back again.  But it was very interesting and a useful distraction.  So, thanks.  I guess...

The Walrus

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Re: The 2020/2021 freezing season
« Reply #706 on: November 03, 2020, 11:25:04 PM »
Nope, definitely the Mpemba effect  ::)

Well, that lead to me using up 15 mins of my life that I will never get back again.  But it was very interesting and a useful distraction.  So, thanks.  I guess...

Yes, I used up about the same amount of time correcting his post.

SimonF92

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Re: The 2020/2021 freezing season
« Reply #707 on: November 04, 2020, 09:43:56 AM »
Sorry both, Mpemba effect is an example of awfully executed pseudoscience- sometimes sarcasm does not carry. Still though, it would be interesting if it was real
Bunch of small python Arctic Apps:
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uniquorn

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Re: The 2020/2021 freezing season
« Reply #708 on: November 04, 2020, 11:12:11 AM »
I made a different daily change graph to get a better view of this year's late refreeze and to compare it with previous years when extent minimum was very low. I also used 7 day trailing averages which seems to help.
Thanks, much clearer.


gmrt bathymetry with amsr2-awi-v103 overlay at 90% with heavy contrast to help view lower concentration ice, oct25-nov3

Siberian coastal ice is shown drifting out to sea. That may fasten up with more northerly winds forecast.

Some discussion upthread about ice movement close to Severnaya Zemlya. It appears that the ice that formed and drifted to the south west did melt or disperse to the point where it became undetectable to amsr2. Too cloudy for viirs brightness temperature to verify, those interested could check if there are any Sentinel images. Coastal Kara ice is spreading from the south east with favourable winds to replace it.

My interest in this presentation is the area north of NSI previously looked at here.
Not much to see but there may be a further weakness over the Lomonosov Ridge. Looking for evidence to identify if there is persistent turbulence causing vertical mixing there.

It's easy to see the more well known turbulent area north east of Chukchi as the warmer Pacific waters sink into the basin.
Recent extent gains have been impressive. There's still a long way to go.
click for movement
« Last Edit: November 04, 2020, 11:56:27 AM by uniquorn »

uniquorn

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Re: The 2020/2021 freezing season
« Reply #709 on: November 04, 2020, 08:07:39 PM »
amsr2-uhh comparison of 2016 and 2020, sep21-nov3.
bad data on 20160924
click for movement (10MB)

Pagophilus

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Re: The 2020/2021 freezing season
« Reply #710 on: November 04, 2020, 09:08:00 PM »
NSIDC comparison tool
Nov 3 2020 vs Nov 3 2019, 2016, 2012.

Pagophilus

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Re: The 2020/2021 freezing season
« Reply #711 on: November 04, 2020, 09:11:26 PM »
Sorry both, Mpemba effect is an example of awfully executed pseudoscience- sometimes sarcasm does not carry. Still though, it would be interesting if it was real
No worries.  I did get the sarcasm.  I think we are both enjoying the whole thing.   :D
« Last Edit: November 05, 2020, 01:29:42 AM by Pagophilus »

El Cid

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Re: The 2020/2021 freezing season
« Reply #712 on: November 04, 2020, 09:32:09 PM »
Actually, we are just about a week behind 2018

uniquorn

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Re: The 2020/2021 freezing season
« Reply #713 on: November 04, 2020, 10:36:32 PM »
Actually, we are just about a week behind 2018
Fair point. ASI location this year is very similar but 2018 is in 6th place so doesn't get much attention. (thanks for the table JCG)

1979-2020 noaa concentration on nov2 is here

Lets look again in a week's time
« Last Edit: November 04, 2020, 10:43:32 PM by uniquorn »

Pavel

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Re: The 2020/2021 freezing season
« Reply #714 on: November 04, 2020, 11:20:45 PM »
Actually, we are just about a week behind 2018
And 2018 was followed by the 2019 melting season. With the one week missing of the freezing season and the lowest volume at the moment it need conditions like the 2017 melt season to avoid new record lows.

Aluminium

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Re: The 2020/2021 freezing season
« Reply #715 on: November 05, 2020, 09:09:29 AM »
October 31 - November 4.

2019.

BornFromTheVoid

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Re: The 2020/2021 freezing season
« Reply #716 on: November 05, 2020, 04:55:19 PM »
5 day centred mean extent increases for the last 30 days. Latest date for 2020 is Nov 1st (so covers October 30th to November 3rd), as I reckon the latest daily update for the 4th is an error.

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

Paul

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Re: The 2020/2021 freezing season
« Reply #717 on: November 05, 2020, 06:02:19 PM »
Actually, we are just about a week behind 2018
And 2018 was followed by the 2019 melting season. With the one week missing of the freezing season and the lowest volume at the moment it need conditions like the 2017 melt season to avoid new record lows.

Does not quite work like that though. As I say, a slow refreeze in Laptev does not mean the Laptev will be the first to melt out next year, volume is very low in that region due to a lack of ice hence why the overall volume is low but with the Laptev freezing over quickly and ice early on thickens quickly, I suspect we won't stay lowest on record in terms of volume although if we have a winter like 2016//17 then we may approach record lows again in volume.

The interesting one for me is CAB volume, that is record low and if that continues, that could be a concern for next year.

gandul

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Re: The 2020/2021 freezing season
« Reply #718 on: November 06, 2020, 06:20:45 PM »
Question: why is taking so long for the Laptev sea to refreeze this year?
https://twitter.com/zlabe/status/1324737964182700033?s=21
« Last Edit: November 06, 2020, 06:30:23 PM by gandul »

Vince O

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Re: The 2020/2021 freezing season
« Reply #719 on: November 07, 2020, 10:10:03 AM »
Hi there all,   well this is my first post though I've been watching things since at least 1990.
  So, though I watch a great deal I don't think I've ever seen the ice start to break apart like JAXA is showing over the last three days. Does this happen ? Is this expected ? It seems a crack is growing though I can't see why. Maybe I'm wrong.

aslan

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Re: The 2020/2021 freezing season
« Reply #720 on: November 07, 2020, 12:42:57 PM »
In the end, could you please stop trolling this forum... Yes, record warmth during the Spring leads to an early break up of the sea ice. A lot of heat has been absorbed by Siberian seas. But, no, this is not just one fluke explaining everything! For one part this is taking place in the general trend of the global warming. And the salinity anomaly, the persistence of the heat anomaly up to now, the fact that the southern Chukchi sea is in an even worst shape, the Atlantic front being fixed north of Svalbard and Severnaya Zemlya etc... All of this is not a direct consequence of a large build up of heat in the Siberian seas in the Spring and Summer.  And yes, this will have long lasting consequences. For example, Ostrov Kotel'Nyj mean temperature is currently (as of the 7th included) a f*****g 7.3°C above the previous record for November (-7.7°C as of the 7th vs -15°C for the whole month of November 2012). Even though the temperatures turn back to average, a new record is virtually certain (small detail, but the SYNOP are still coding CBs at this time of year, which is even more extraordinary). Even more extraordinary is the heat record for Cape Tchelouskyne. Freezing degree days are near the record low level of 2016 for the whole Arctic bassin, and as the sea ice is slow to build up, this means that a weak and vulnerable first year ice next Spring is already locked in. This does not mean that there will be a catastrophe next Spring. Only that this increase greatly the probability of such a catastrophe, even with a more average Spring.
Things are not as simple as : some heat wave happening by chance in Spring -> oh a warm Autumn ! -> Yeah but evrything will ease back to average this Winter, we are fine for the next Spring.

P.S. : If Mercator bulletin is of any usefulness, Laptev salinity is around 34 PSU from top to bottom, and it remains to prove that a heat wave can lead to such a salinity anomaly...
« Last Edit: November 07, 2020, 01:03:30 PM by aslan »

gerontocrat

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Re: The 2020/2021 freezing season
« Reply #721 on: November 07, 2020, 03:55:27 PM »
The late refreeze in the Laptev is the inevitable result of a multi-year process - the extreme Siberian heat this year has given that process an additional shove on all the seas bordering Siberian Russia.

As yet, that increasing early melt and longer ice free period does not seem to have affected winter sea ice area and extent cover. (Volume is a different story).  My guess is that one year it will, especially as the attached open water graphs show how this Atlantification process has spread from the Barents to the Laptev and has reduced winter sea ice cover in the Barents and Kara.
___________________________________________________________
ps:-I have added the ESS graph - which I reckon is being attacked by Atlantification and Pacification.

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gandul

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Re: The 2020/2021 freezing season
« Reply #722 on: November 07, 2020, 04:49:55 PM »
In the end, could you please stop trolling this forum... 
I don’t know who are you talking to but in my experience, “troll” is often the expletive used by those who want an all-agree uniform discussion.

Northern Laptev salinity: there are documents back in the 90’s describing the surface salinity level shown in Mercator. Nothing new.

ftp://ftp.nodc.noaa.gov/nodc/archive/arc0001/9800040/1.1/data/0-data/atlas/html/intro/intro_lp.htm

gandul

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Re: The 2020/2021 freezing season
« Reply #723 on: November 07, 2020, 05:28:09 PM »
The late refreeze in the Laptev is the inevitable result of a multi-year process - the extreme Siberian heat this year has given that process an additional shove on all the seas bordering Siberian Russia.

As yet, that increasing early melt and longer ice free period does not seem to have affected winter sea ice area and extent cover. (Volume is a different story).  My guess is that one year it will, especially as the attached open water graphs show how this Atlantification process has spread from the Barents to the Laptev and has reduced winter sea ice cover in the Barents and Kara.
___________________________________________________________
ps:-I have added the ESS graph - which I reckon is being attacked by Atlantification and Pacification.

Multiyear? So what happened in 2016 and in 2017. The Atlantification of the Laptev took a break??

I remember well both springs. 2016 was warm everywhere, but the Laptev coast melting suffered a delay due to the fact that a lot of ice drift streamlines had been converging during winter/spring toward ESS and Laptev, and the transpolar had been disrupted that winter not inducing as much peel-off on the Laptev coasts, leading to a high Laptev ice volume.

In 2017 spring simply started a few weeks late especially in Eurasia due to the high snow cover volume and late thaw. The whole summer was relatively cold.

I bet the relentless reduction of ice in Laptev can be explained by atmospheric climate change without having to resort to the obscure hypotheses of Atlantic Water effects. Global warming effects on oceans is slow and often counterintuitive. Reserves for heat are enormous given the dimensions and the heat capacity. Characteristic times of change are of the order of hundred years.

Granted, it is more entertaining and novel-esque to focus the attention on impossible to verify heat sources and impossible to measure methane time-bombs. To each their own.

oren

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Re: The 2020/2021 freezing season
« Reply #724 on: November 07, 2020, 05:59:52 PM »
Hi there all,   well this is my first post though I've been watching things since at least 1990.
  So, though I watch a great deal I don't think I've ever seen the ice start to break apart like JAXA is showing over the last three days. Does this happen ? Is this expected ? It seems a crack is growing though I can't see why. Maybe I'm wrong.
Welcome, Vince O.

Jim Hunt

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Re: The 2020/2021 freezing season
« Reply #725 on: November 07, 2020, 06:21:38 PM »
Hi there all,

Hi Vince,

You may wish to check out the SMOS "thin sea ice thickness" product:

https://seaice.uni-bremen.de/databrowser/#p=smos

Does this show the "cracking" you refer to?
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

uniquorn

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Re: The 2020/2021 freezing season
« Reply #726 on: November 07, 2020, 09:28:45 PM »
The interesting one for me is CAB volume, that is record low and if that continues, that could be a concern for next year.
This may not affect volume too much but the CAB is still very sensitive to prevailing winds along the Atlantic front. Extent drifted further into uncharted territory yesterday and looks like it may drop a little more today.

amsr2 awi v103, nov6-7
wipneus CAB extent, nov6

aslan

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Re: The 2020/2021 freezing season
« Reply #727 on: November 07, 2020, 09:56:09 PM »

Multiyear? So what happened in 2016 and in 2017. The Atlantification of the Laptev took a break??

I remember well both springs. 2016 was warm everywhere, but the Laptev coast melting suffered a delay due to the fact that a lot of ice drift streamlines had been converging during winter/spring toward ESS and Laptev, and the transpolar had been disrupted that winter not inducing as much peel-off on the Laptev coasts, leading to a high Laptev ice volume.

In 2017 spring simply started a few weeks late especially in Eurasia due to the high snow cover volume and late thaw. The whole summer was relatively cold.

I bet the relentless reduction of ice in Laptev can be explained by atmospheric climate change without having to resort to the obscure hypotheses of Atlantic Water effects. Global warming effects on oceans is slow and often counterintuitive. Reserves for heat are enormous given the dimensions and the heat capacity. Characteristic times of change are of the order of hundred years.

Granted, it is more entertaining and novel-esque to focus the attention on impossible to verify heat sources and impossible to measure methane time-bombs. To each their own.

Troll is for someone flooding the forum with the same argument over and over, ignoring the contributions of the others members.
Multi year does NOT mean it is monotonically worst year after year, but that it is a trend. The year 2012 was worst than the year 2007, the year 2016 was worst than the year 2012, and the year 2020 is worst than the year 2016. Perhaps 2021 will be even worst, perhaps not, who know. But only for you does a trend mean each year being monotonically and significantly worst than the preceding year.
And again, at some point which is now probably really not that far away, the trend will overwhelmed the Arctic and tip the Kara sea to a perenially open sea (and the Laptev and Chuckchi are next in line).
In your document, salinity is described as being in the range 22 to 32 PSU at surface, reaching 33 to 34.5 PSU at one hundred meters (100 meters). Just read...

Quote
The temperature and salinity fields show large gradients between the mixing zones of river and sea water and the uniform thermohaline structure of the northern Laptev Sea. In the wintertime, due to a sharp decrease in runoff, increase in ice cover, and decrease in convection processes, the thermohaline structure is relatively homogenous. The water temperature varies from -1.4° in the eastern sea, up to -0.8° in the northwestern sea. The water salinity in the southwestern sea has values of 22-24 0/00, smoothly increasing northward and to the northwest up to 32-34 0/00. Figure 7 shows the vertical temperature and salinity profiles for the western, southeastern, and northern regions of the Laptev Sea in the summertime. In summer the southwestern upper 15 meter layer is warmed to a temperature of 5 ° - 7° . In the southeastern part, temperatures increase to 1° and remain about -1° in the northern areas. In winter a vertical temperature and salinity distribution in the shallow area is quite uniform, the salinity weakly increasing with depth and the temperature being within -0.5° - 1.9° C, depending on the region. In the deep northern Laptev Sea a temperature maximum is observed at a level of 100-400 m, the salinity dramatically increases from the surface to a 100 m level from 29 to 33-34.5 0/00 and changes little at greater depths.

This year, we are speaking of salinity significantly above 34 PSU, nearing 34.5 PSU if we trust MERCATOR, at surface, in winter, in Laptev. Not at a depth of 100 or 800 meters, at surface.
And you don't answer the question, why then the ice boundary is set northward of 81 - 82°N or something like this, from Svalbard to Severnaïa Zemlaïa, if this is just some direct consequence of huge inertia from the Spring heat wave over Siberia (and by the way why there is still probably some bottom melt ongoing there, to be exhaustive).
« Last Edit: November 07, 2020, 10:03:56 PM by aslan »

aslan

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Re: The 2020/2021 freezing season
« Reply #728 on: November 07, 2020, 10:36:17 PM »
And weather forecast is not encouraging. Likely not as worst as mid November 2016 (second picture), but still quite bad with a strong low and a massive heat advection.

oren

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Re: The 2020/2021 freezing season
« Reply #729 on: November 07, 2020, 11:04:12 PM »
Aslan, while I support your science position here, plrase avoid troll name calling. I will monitor what feels like a pet theory situation, but please leave it to me. Otherwise flames will go higher when they should go lower.

Vince O

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Re: The 2020/2021 freezing season
« Reply #730 on: November 08, 2020, 03:20:35 AM »
Hi Jim, thanx but no Todays JAXA / AMSR2 graphic again shows a bigger area of disappearing ice which I've never seen before in the near five years I've been watching JAXA. Here's the new image. Maybe it's an anomaly but for four days in a row now and growing. . . ?  I looked on Polarview to check and there is thinning in the same area but the picture is from a few days back when it wasn't so prominent.

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Re: The 2020/2021 freezing season
« Reply #731 on: November 08, 2020, 11:10:40 AM »
Todays JAXA / AMSR2 graphic again shows a bigger area of disappearing ice which I've never seen before in the near five years I've been watching JAXA.

So that's the Kara Sea ice edge? I still can't work out what you're referring to. Can you annotate an image to clarify?
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Vince O

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Re: The 2020/2021 freezing season
« Reply #732 on: November 08, 2020, 11:23:33 AM »
Here, I thought I did. Like I said, maybe it's a JAXA software anomaly but its getting bigger

gerontocrat

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Re: The 2020/2021 freezing season
« Reply #733 on: November 08, 2020, 01:05:15 PM »
Looks like a satellite problem for Univ Bremen
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Re: The 2020/2021 freezing season
« Reply #734 on: November 08, 2020, 05:02:51 PM »
Here, I thought I did.

You may know what you're looking at, but I still don't!

What I had in mind was something like this:

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

oren

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Re: The 2020/2021 freezing season
« Reply #735 on: November 08, 2020, 05:06:22 PM »
I think Vince O means this, in the image he uploaded.
However I think it's an artifact that can be ignored, as it does not seem to appear in the other products posted here.


Pagophilus

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Re: The 2020/2021 freezing season
« Reply #736 on: November 08, 2020, 05:07:28 PM »
I bet the relentless reduction of ice in Laptev can be explained by atmospheric climate change without having to resort to the obscure hypotheses of Atlantic Water effects. Global warming effects on oceans is slow and often counterintuitive. Reserves for heat are enormous given the dimensions and the heat capacity. Characteristic times of change are of the order of hundred years.

The atmosphere and oceans form an integrated system, so I think arguing a solely atmosphere-based effect hypothesis for any changes in the Arctic (beyond short-term effects on the order of a week or a month) is perilous. Most of the extra heat that is trapped by our planet due to climate change is going into the oceans, and you are correct of course: that quantity of heat is enormous.

The effects of the this heating of the oceans may only show up gradually, but does it then follow that these effects are somehow not now showing up in the Laptev now, following at least a century of oceanic warming?  A warming effect can be gradual (as you state it is in the oceans) and it can then manifest itself rather dramatically through the medium of ice extent, since this phase transition is so dramatic to us. 

I am not expert enough to argue whether or not Atlantification of the Laptev is taking place. I am not denying that the extreme Siberian heat this summer did not have a profound effect on the adjacent seas, and particularly the Laptev -- that seems evident to me.  But I agree with aslan that taking a more holistic approach, and looking at trends over several years, including both atmospheric and ocean effects, is the more logical way to approach this.
« Last Edit: November 08, 2020, 05:22:28 PM by Pagophilus »

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Re: The 2020/2021 freezing season
« Reply #737 on: November 08, 2020, 08:06:46 PM »
    And now we can add warm Siberian river drainage into the Arctic Ocean as another factor (article posted upthread).  Given the record breaking high Siberian temperatures over land in summer 2020, the river water draining those areas must have been especially warm.

oren

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Re: The 2020/2021 freezing season
« Reply #738 on: November 08, 2020, 10:08:42 PM »
I did try to find temperature data of the Lena in real time, and compare to other years, but found the task beyond my abilities although I am quite sure the data exists. Maybe some Russian speaker here can manage to find this data.

There was a thread dealing with river discharge and other related issues.
https://forum.arctic-sea-ice.net/index.php/topic,3034.0.html

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Re: The 2020/2021 freezing season
« Reply #739 on: November 08, 2020, 10:22:38 PM »

Pavel

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Re: The 2020/2021 freezing season
« Reply #740 on: November 09, 2020, 09:15:30 AM »
I've found this russian site
https://travel.org.ua/water/ijul/reka-lena-(vozle-yakutska)-temperatura-vody
For examle, this is a chart of July 2020 compared with July 2019 water temperature on the Lena rive near Yakutsk

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Re: The 2020/2021 freezing season
« Reply #741 on: November 09, 2020, 10:43:16 AM »
    And now we can add warm Siberian river drainage into the Arctic Ocean as another factor (article posted upthread).  Given the record breaking high Siberian temperatures over land in summer 2020, the river water draining those areas must have been especially warm.
Yes, but in context, not a major player in the total energy equation currently playing out.  The impact of circum-arctic drainage is much more important early in the melt season.  Once albedo drops and insolation rises, the effect of a few thousand km3 of warmer water becomes less significant.  At this point in the year, it is of far less import than continuing inflow from Atlantic currents and atmospheric circulation where the remnants of tropical storms drag huge influxes of moisture into the Arctic.
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jdallen

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Re: The 2020/2021 freezing season
« Reply #742 on: November 09, 2020, 11:00:31 AM »
I'll try to put my thoughts together in something more coherent, but let me put it this way, at the most elemental level:

It's all about Enthalpy.

Increased capture, reduced outgoing radiation mean the total heat present in the Arctic ocean has greatly increased.  (restricted by increased water vapor content in the atmosphere, along with additional CH4 and the increases in CO2... remember just how powerful a green house case H20 is...)

Ice can't form until sufficient heat has left the ocean surface to permit phase change to take place.  We already know that the water column has been disrupted, and that Atlantic water (and heat carried with it) is much closer to the surface and more accessible than the past.

Simply put, with the current energy balance, the Arctic can't dump the heat fast enough.

Even without the present throttling effects of weather (higher atmospheric temperatures and increased humidity, among other factors), the typical export of heat out of the atmosphere is not going to be able to dissipate the additional heat captured during the melt season. Heat simply won't get radiated out of the top of the atmosphere fast enough.

So, the bigger pile means there is that much more heat present which must get moved *somewhere* before the physics of phase change will permit the ice to form, over very large areas of the Arctic.

Unfortunately I don't have quantitative values to present here on this, but I think the qualitative argument should still be compelling.  As a rough estimate, the Arctic picked up something like 30% more energy this year during the melt season, *before* we factor in intrusion of Atlantic heat.

It can't get dumped fast enough.
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grixm

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Re: The 2020/2021 freezing season
« Reply #743 on: November 09, 2020, 01:32:14 PM »
We might see some extent stalling, even losses, in around 5+ days, as the Kara sea, which has a lot of thin ice and is one of the main growth frontiers now that the laptev is all but closed, will likely experience a surge of warm air from the Atlantic. Even a large portion of the CAB is forecast to see above-freezing temps for a spell.
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oren

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Re: The 2020/2021 freezing season
« Reply #744 on: November 09, 2020, 02:27:14 PM »
jdallen, well written but I believe at the qualitative level (the only level I am able to discuss) there is also salinity. Those seas (especially Laptev) that melted first and had lots of time under an open water regime and with lots of wind this year in the Arctic, have had time to mix the fresh surface layer that results from ice melt and river discharge, therefore making refreeze even harder and more delayed than if just enthalpy was involved.

gandul

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Re: The 2020/2021 freezing season
« Reply #745 on: November 09, 2020, 03:39:16 PM »
Yes, well, salty water that eventually finds its way down, along with the excess salt of the freezing surface, to beneath the mixed layer by something called gravity leaving renovated with river runoff the fresher (and freezing) water at the top.
That’s why, according to textbooks, and until this date (the opposite not been seen empirically, ever) there’s an halocline in the Arctic occupying ample vertical space in the band 50-200 m between the mixed layer and the Atlantic water.

And this halocline is why the Arctic has been protected from the Atlantic Water mass heat at >200 m for hundreds or thousands of years (textbook stuff).

https://doi.org/10.1016/0198-0149(81)90115-1

Note that, at that time the authors were worried with river water diversions. Funny how things change.



oren

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Re: The 2020/2021 freezing season
« Reply #746 on: November 09, 2020, 04:08:42 PM »
Gandul you are running with a pet theory and it is disruptive.
The halocline can be disrupted, as happened in the Barents. Not been seen empirically ever? I think you are wrong. I am not at the level to do battle and not enough time on my hands but I do not wish this to be posted and reposted without sufficient scientific backing. If you wish, start a new thread about Atlantification yes or no, or something like that, and there it can be discussed to your heart's content and in the appropriate level to refute and/or understand stuff without disrupting the main thread.
Otherwise I will remove and edit as I see fit.

sailor

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Re: The 2020/2021 freezing season
« Reply #747 on: November 09, 2020, 04:53:04 PM »
Guys could we please end this off-topic for this thread?
Oren, Gandul, JD, Aslan, etc. please let's keep the focus on the 2020 freezing season.
Gandul, you couldn't shup up could you? Valuable contrubutors are leaveing the thread, again.

uniquorn

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Re: The 2020/2021 freezing season
« Reply #748 on: November 09, 2020, 05:42:10 PM »
I think Vince O means this, in the image he uploaded.
However I think it's an artifact that can be ignored, as it does not seem to appear in the other products posted here.
amsr2 shows lower concentration ice in the same area yesterday with some persistence over the last 3 days further east. It looks like the wet ice we see during the melting season but it has been too cold for that. Perhaps some fog related event from opening leads.
Brightness temperature bands are interesting to explore during winter night.
3 are shown below (click). The link provides 4 of them already set up.
https://go.nasa.gov/3kimitP

BornFromTheVoid

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Re: The 2020/2021 freezing season
« Reply #749 on: November 09, 2020, 06:36:38 PM »
The Atlantic edge pushing northward quite quickly so far this month

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