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Positive retroaction

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Re: The 2020/2021 freezing season
« Reply #800 on: November 14, 2020, 10:15:52 PM »


On Kara, vize, the lowest temperature of the month, -8.5 ° C, is more than 10 ° C above the average temperature of a normal month of November (-18.5 ° C)
Even if we are on the half of the month, is very impresive

Indeed, it seems far from being a record of extent or precocity
Hudson for nsidc
Sorry, excuse my bad english

bbr2315

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Re: The 2020/2021 freezing season
« Reply #801 on: November 14, 2020, 10:48:39 PM »
And yet bbr, according to AMSR2 Hudson Bay has barely reached 100k km2, more than two weeks after 2015 and 2018 and almost the latest in the AMSR2 record. So I think you are basing your predictions on something that is not accurate.
There is cloud interference and Foxe Basin is what accounts for those years as I explained in my post.

Here is 12z EURO 00z hr vs D10. I think it will freeze a bit faster and more solidly than modeled.


Aluminium

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Re: The 2020/2021 freezing season
« Reply #802 on: November 15, 2020, 07:42:39 AM »
November 9-14.

2019.

Positive retroaction

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Re: The 2020/2021 freezing season
« Reply #803 on: November 15, 2020, 01:19:50 PM »
November 9-14.

2019.
It's nice to see an ice floe again connected to the eastern lands (even if I m conscient that is dramatic to have this situation so late on the freeze season)
The wait was so long that this image became a memory
It doesn't bring much but I just share an impression
Sorry, excuse my bad english

grixm

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Re: The 2020/2021 freezing season
« Reply #804 on: November 15, 2020, 02:02:37 PM »
Daily area dropped today, for the first time in almost a month.

Pagophilus

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Re: The 2020/2021 freezing season
« Reply #805 on: November 15, 2020, 02:35:55 PM »
NSIDC Spatial Ice Extent comparison     Nov 13 2020 vs Nov 13 2019, 2016, 2012

As the plots of ice extent converge on the graphs, so does the ice's geographical distribution look more and more similar. 

Eyeballing 2020-2016 map, 2016's current #1 status looks to be largely due to its slower refreeze in the northern Kara Sea.

2012, which forms almost an overlay with 2020, would also be in the running with it's slow refreeze of the northern Kara, but it isn't because much of the Chukchi froze over by Nov 13.

« Last Edit: November 16, 2020, 01:19:18 AM by Pagophilus »

NotaDenier

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Re: The 2020/2021 freezing season
« Reply #806 on: November 15, 2020, 02:43:03 PM »
I was wondering if there is a way to see how “full” the 7 central arctic seas are compared to the periphery seas. I looked Wipenus’s home brew and guesstimate 90% of the arctic ocean is now covered. With only the Chukchi and the Kara Sea having room for growth.

What I am getting it is, would it be worth figuring out the date the central seas are completely iced over?

Most growth from now will be in the periphery seas, this growth does not effect the end result of the melting season. (Or effects it very little)

uniquorn

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Re: The 2020/2021 freezing season
« Reply #807 on: November 15, 2020, 02:49:46 PM »
amsr2 awi v103, nov14 overlaid onto gmrt bathymetry. (click)
While the ice is still thin it is possible to discern some ocean activity.

Leads north of the chukchi align with the shelf break and chukchi plateau topography where sinking Pacific water causes turbulence and possible mixing.
The remaining open water in the Laptev sits over the shear zone at the eastern edge of the Nansen basin. This is where incoming atlantic water is forced to turn back towards the Fram or attempt to rise up the shelf. Note also the low concentration ice along the shelf break north of SZ.

Some incoming Atlantic water from the Barents limits refreeze in the Kara to the fresher surface layer in the shallower coastal area but most continues north, sinking into the St Anna trough between SZ and FJL.

Most Atlantic water enters via the Fram strait, passing to the north of Svalbard and FJL, sinking along the shelf as it moves east.

https://www.nature.com/scitable/knowledge/library/arctic-ocean-circulation-going-around-at-the-102811553/
« Last Edit: November 15, 2020, 04:47:18 PM by uniquorn »

gerontocrat

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Re: The 2020/2021 freezing season
« Reply #808 on: November 15, 2020, 04:13:03 PM »
Today's a warm day on the Atlantic Front
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
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jdallen

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Re: The 2020/2021 freezing season
« Reply #809 on: November 15, 2020, 11:03:50 PM »
Today's a warm day on the Atlantic Front
This has been a consistent pattern since the start of the refreeze.  It's been book-ended by cold air being flushed out of the Arctic, breaking south across the Canadian shield into the US great plains.

Here's the September anomaly map from Climate Reanalyzer.  I'll be interested to see Octobers when it turns up, and Nov. after that to see if my hunch is borne out.

« Last Edit: November 16, 2020, 02:33:21 AM by oren »
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Pagophilus

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Re: The 2020/2021 freezing season
« Reply #810 on: November 16, 2020, 01:09:23 AM »
I was wondering if there is a way to see how “full” the 7 central arctic seas are compared to the periphery seas. I looked Wipenus’s home brew and guesstimate 90% of the arctic ocean is now covered. With only the Chukchi and the Kara Sea having room for growth.

What I am getting it is, would it be worth figuring out the date the central seas are completely iced over?

Most growth from now will be in the periphery seas, this growth does not effect the end result of the melting season. (Or effects it very little)
I can't offer data (much too far down the food chain) but here is the NSIDC comparison map showing all the peripheral seas for Nov 13, 2020 vs Nov 13, 2019.  Hope it helps a bit. 
« Last Edit: November 16, 2020, 01:21:54 AM by Pagophilus »

oren

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Re: The 2020/2021 freezing season
« Reply #811 on: November 16, 2020, 02:36:35 AM »
Wipneus comes to the rescue with his pair of useful charts, multi-product Arctic Basin area and extent.




Cook

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Re: The 2020/2021 freezing season
« Reply #812 on: November 16, 2020, 02:51:55 AM »
Just a question in the hope someone can answer it easily. Is this the first time in known history that the area around Franz Josef Land is ice free in mid November?

oren

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Re: The 2020/2021 freezing season
« Reply #813 on: November 16, 2020, 03:21:50 AM »
So, a quick visit to Worldview can help answer the question.
Sample Worldview link
Choose Add Layers - Sea Ice - SSMI - Sea Ice Concentration. Now you can see sea ice extent all the way to 1978, and even better you can click the video camera icon to make an animation of up to 40 frames, with 1 year increments showing you the same date every year. Download the result, and upload to ezgif.com for some optimization, resizing and setting desired delays between frames.
And the answer: It seems 2012 was worse.

Click to animate.

Cook

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Re: The 2020/2021 freezing season
« Reply #814 on: November 16, 2020, 03:31:36 AM »
Amazing, a big thank you.

El Cid

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Re: The 2020/2021 freezing season
« Reply #815 on: November 16, 2020, 07:17:34 AM »
Here's the September anomaly map from Climate Reanalyzer.  I'll be interested to see Octobers when it turns up, and Nov. after that to see if my hunch is borne out.

wait no more:

El Cid

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Re: The 2020/2021 freezing season
« Reply #816 on: November 16, 2020, 07:32:26 AM »
and this one is November so far(1st pic):

warm Eurasia (trend continues from Sept/Oct, likely due to open Siberian seas), cold Canada (bbr likes this) and warm US.

...during the past three years we had open siberian seas for very long and the pattern for October for these three years is similar (2nd pic), probably not a coincidence that Eurasia was very warm and NA cold

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Re: The 2020/2021 freezing season
« Reply #817 on: November 16, 2020, 07:49:02 AM »
Today's a warm day on the Atlantic Front
And nice 7 - 9 m waves most of today.

SimonF92

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Re: The 2020/2021 freezing season
« Reply #818 on: November 16, 2020, 11:31:33 AM »
Ran the regional script again
Bunch of small python Arctic Apps:
https://github.com/SimonF92/Arctic

Shared Humanity

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Re: The 2020/2021 freezing season
« Reply #819 on: November 16, 2020, 01:49:51 PM »
Today's a warm day on the Atlantic Front

Must be coming with some high winds too.

bbr2315

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Re: The 2020/2021 freezing season
« Reply #820 on: November 16, 2020, 04:59:29 PM »
Here's the September anomaly map from Climate Reanalyzer.  I'll be interested to see Octobers when it turns up, and Nov. after that to see if my hunch is borne out.

wait no more:
The "triangle of cold" is perfectly illustrated here...

Canuck maps show Hudson refreeze is progressing rapidly, I anticipate the evacuation of all this heat / release of heat associated with freezing will deal the ATL front continued blows for the next few weeks, I would not be surprised to see the front retreat dramatically in Kara / Laptev / Barentz vicinity.

oren

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Re: The 2020/2021 freezing season
« Reply #821 on: November 16, 2020, 09:36:23 PM »
Hudson Bay sea ice area according to AMSR2. Progressing rapidly perhaps, but not quite as rapidly as other years.

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Re: The 2020/2021 freezing season
« Reply #822 on: November 16, 2020, 10:08:38 PM »
Canuck maps show Hudson refreeze is progressing rapidly, I anticipate the evacuation of all this heat / release of heat associated with freezing will deal the ATL front continued blows for the next few weeks, I would not be surprised to see the front retreat dramatically in Kara / Laptev / Barentz vicinity.
Hudson and areas surrounding it are indeed forecasted to be much colder than average. And everything between Bering Sea and Barents Sea (including Beaufort) is relatively warm (7 day forecast mean).

Positive retroaction

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Re: The 2020/2021 freezing season
« Reply #823 on: November 17, 2020, 12:16:20 PM »
19,5 °C positive anomaly yesterday on Golomyanny island

18,4°C positive anomaly on vize island
Sorry, excuse my bad english

Pagophilus

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Re: The 2020/2021 freezing season
« Reply #824 on: November 17, 2020, 02:38:49 PM »
19,5 °C positive anomaly yesterday on Golomyanny island

18,4°C positive anomaly on vize island
Thank you Positive retroaction.  Startling figures.  From my point of view, it would be great to know the absolute temperatures as well.   

Positive retroaction

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Re: The 2020/2021 freezing season
« Reply #825 on: November 17, 2020, 03:28:20 PM »
19,5 °C positive anomaly yesterday on Golomyanny island

18,4°C positive anomaly on vize island
Thank you Positive retroaction.  Startling figures.  From my point of view, it would be great to know the absolute temperatures as well.

Yes, it's true
In golomany, yesterday had a minimum temperature of -3.5 ° C, an average temperature of -1.3 ° C and a maximum temperature of -0.9 ° C
On that day, November 17, the normal temperature was -21.5 ° C.

For the island of vize, the minimum temperature yesterday was -5.5 ° C
The average temperature was -0.3 ° C
The maximum 0.1 ° C
The normal average temperature is -18.7 ° C

More generally, anomalies between 9 and 11 degrees last for more than 1 month without stopping
Sorry, excuse my bad english

SimonF92

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Re: The 2020/2021 freezing season
« Reply #826 on: November 17, 2020, 03:35:14 PM »
Bunch of small python Arctic Apps:
https://github.com/SimonF92/Arctic

aslan

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Re: The 2020/2021 freezing season
« Reply #827 on: November 17, 2020, 06:50:42 PM »
19,5 °C positive anomaly yesterday on Golomyanny island

18,4°C positive anomaly on vize island
Thank you Positive retroaction.  Startling figures.  From my point of view, it would be great to know the absolute temperatures as well.

Yes, it's true
In golomany, yesterday had a minimum temperature of -3.5 ° C, an average temperature of -1.3 ° C and a maximum temperature of -0.9 ° C
On that day, November 17, the normal temperature was -21.5 ° C.

For the island of vize, the minimum temperature yesterday was -5.5 ° C
The average temperature was -0.3 ° C
The maximum 0.1 ° C
The normal average temperature is -18.7 ° C

More generally, anomalies between 9 and 11 degrees last for more than 1 month without stopping

To be fully exhaustive, August and September were more extreme than November as far as gap from the normal is considered. At Ostrov Vize, November 2020 is lagging a bit behind November 2016 for now, and no new record as been registered. Way above normal, but still within the (temporarily and for now...) known climatology. At Kotel'Nyj or Mys Tchelouskine there is a higher chance that November could be a record (especially Kotel'Nyj actually), but we are not fully at the same level of extreme than in 2016 overall. This said, winds are also in play. Even though no new wind record as been set to my knowledge, the Atlantic front has been battered for sure. Probably the most noteworthy is Ostrov Heiss with wind speed up to 30 m/s... The sea ice has been damaged, being highly fractured and locally reduced to a crumble of tiny floes : https://worldview.earthdata.nasa.gov/?v=-107366.71760836348,-806019.2028485272,1669789.9532940923,39981.42069566273&p=arctic&t=2020-11-17-T02%3A00%3A00Z&l=Coastlines,AMSRU2_Sea_Ice_Concentration_12km(max=30),VIIRS_NOAA20_Brightness_Temp_BandI5_Night(palette=rainbow_2,min=227.6,max=277.2,squash=true),VIIRS_SNPP_Brightness_Temp_BandI5_Day(hidden,palette=rainbow_2,min=227.6,max=277.2,squash=true),Reference_Labels(hidden),Reference_Features(hidden),VIIRS_NOAA20_CorrectedReflectance_TrueColor(hidden),VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor
« Last Edit: November 17, 2020, 07:06:05 PM by aslan »

Pagophilus

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Re: The 2020/2021 freezing season
« Reply #828 on: November 17, 2020, 06:51:13 PM »
19,5 °C positive anomaly yesterday on Golomyanny island

18,4°C positive anomaly on vize island
Thank you Positive retroaction.  Startling figures.  From my point of view, it would be great to know the absolute temperatures as well.

Yes, it's true
In golomany, yesterday had a minimum temperature of -3.5 ° C, an average temperature of -1.3 ° C and a maximum temperature of -0.9 ° C
On that day, November 17, the normal temperature was -21.5 ° C.

For the island of vize, the minimum temperature yesterday was -5.5 ° C
The average temperature was -0.3 ° C
The maximum 0.1 ° C
The normal average temperature is -18.7 ° C

More generally, anomalies between 9 and 11 degrees last for more than 1 month without stopping
Thank you!  Of note... the average air temperatures are above those at which sea ice typically forms...  Ocean surface temperature is paramount, of course.
« Last Edit: November 17, 2020, 07:00:52 PM by Pagophilus »

aslan

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Re: The 2020/2021 freezing season
« Reply #829 on: November 17, 2020, 07:32:22 PM »
To be clear, because I am not sure I have state explicitly my point. I wanted to emphasize that an anomaly is not only stated by its absolute value. Deviation from normal is also a function of the normal spread. In winter in Arctic, an anomaly of 2-3°C is almost nothing while such an anomaly in the deep tropics could mean breaking a heat record. I did though that the heat could be more extreme than in 2016 for the Barents, but it was not fully the case. Heat is still extreme with some record (especially the 9.2°C reading of the Svalbard airport), but overall we are still within the boundary of the known climatology for this region in November. To the difference with August and September when anomalies expressed in absolute values were lower but were also way outside anything known.

P.S. : Or to put it more bluntly, in August and September, the red line was continuously way above the red dot at the top of the chart...

Positive retroaction

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Re: The 2020/2021 freezing season
« Reply #830 on: November 17, 2020, 11:07:41 PM »
To be clear, because I am not sure I have state explicitly my point. I wanted to emphasize that an anomaly is not only stated by its absolute value. Deviation from normal is also a function of the normal spread. In winter in Arctic, an anomaly of 2-3°C is almost nothing while such an anomaly in the deep tropics could mean breaking a heat record. I did though that the heat could be more extreme than in 2016 for the Barents, but it was not fully the case. Heat is still extreme with some record (especially the 9.2°C reading of the Svalbard airport), but overall we are still within the boundary of the known climatology for this region in November. To the difference with August and September when anomalies expressed in absolute values were lower but were also way outside anything known.

P.S. : Or to put it more bluntly, in August and September, the red line was continuously way above the red dot at the top of the chart...

Totally agree
We have just entered a period of the year when the variability is very high
Even if we are high in 2020, we stay in the known area, but permanently high
It is the continuity of the positive anomaly that concerns me
And its average magnitude, over the entire period, from July to now without stopping
In July, August and September, the variability is very low, but here we have flown above old records
Two months in a row of all-time highs and so far above variability is like a new climate state
I think if there is a tipping point in the arctic, kara will really be one of the seas that gives the imminent signs of this

I don t have the competence for this, but would anyone be interested in performing these things?
Lately I have seen that some people here are really good at representing reality on a graph, so that we can understand and see it.
So I put 2 links, where you will find all the weather reports in vize since 945-11-01
1950_2020-11-09
https://cdiac.ess-dive.lbl.gov/ftp/russia_daily/Russia_stations/20069.txt
The last 50 days
https://www.ogimet.com/cgi-bin/gsodres?lang=en&mode=0&state=Russ&ind=20069&ord=REV&ano=2020&mes=11&day=17&ndays=50
Maybe other links are better, sorry I m new for data treatment
But probably is profitable to put this realty on image, I wanted to do that since some weeks but I not succeed

I also post this
Average temperatures on August on vize Island
And average temperatures on September on vize Island

Data sources www.infoclimat.fr
« Last Edit: November 17, 2020, 11:26:29 PM by Positive retroaction »
Sorry, excuse my bad english

aslan

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Re: The 2020/2021 freezing season
« Reply #831 on: November 17, 2020, 11:25:02 PM »
http://pogodaiklimat.ru/history/20069.htm

(and you just have to change the WMO id : 20046 for Heiss, 20087 for Golommjannyj, 21432 for Kotel'Nyj, 20292 for Mys Tchelouskine -the best one, longest record and craziest anomalies !, etc...)

Currently I am already working on two differents ideas (not directly related to Arctic sea ice...) so I don't have time to work out on the anomalies on the Russian islands. But for sure something is happening... Also, question mark is the method for computing monthly mean. Pogodaiklimat uses the mean of the height three hourly synoptic time (00Z, 03Z, etc...) to my knowledge. Which can change a bit the end result, as others sites can compute from the mean of Tx and Tn, or mean of six hourly synoptic time (?). There is also some errors, at least for Pogodaiklimat. For example, early datas for Golommjannyj. Should be worth a look. But in the end, yeah something get totally broken in August, and it is still ongoing.

Positive retroaction

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Re: The 2020/2021 freezing season
« Reply #832 on: November 17, 2020, 11:30:08 PM »
Thanks for reporting errors
I will try, I start with excel
Thank you
Sorry, excuse my bad english

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Re: The 2020/2021 freezing season
« Reply #833 on: November 18, 2020, 08:32:11 AM »
November 12-17.

2019.

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Re: The 2020/2021 freezing season
« Reply #834 on: November 18, 2020, 09:04:56 AM »
what a retreat on the kara sea!
Sorry, excuse my bad english

jdallen

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Re: The 2020/2021 freezing season
« Reply #835 on: November 19, 2020, 07:03:13 AM »
what a retreat on the kara sea!

I think we are going to see that as long as the hurricane season continue spawning storms.  After they break up, they still carry a huge amount of energy which consistently is being thrust north along the NAM eastern seaboard to blow into the Barents and Kara, with the last remnants being spun into the central basin proper.

This is the same rough pattern that first evolved in 2016 and has to a greater or lesser degree been continuing the last 4 years, and suggests a possible new weather regime.
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Freegrass

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Re: The 2020/2021 freezing season
« Reply #836 on: November 19, 2020, 07:17:28 AM »
Latest Five Day Forecast + Last 24h
Wind + Temp @ Surface
Large GiF!

Where did the Arctic winter go? Did Santa Claus go in quarantine?
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...

Pagophilus

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Re: The 2020/2021 freezing season
« Reply #837 on: November 19, 2020, 01:52:44 PM »
what a retreat on the kara sea!
I wonder how much of that dramatic retreat in the Kara was due to the newly formed ice being melted, and how much was simply crushed into a smaller area by the winds?  Either way, not good, but melting would be more alarming, IMO.

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Re: The 2020/2021 freezing season
« Reply #838 on: November 19, 2020, 03:34:06 PM »
The daily NSIDC extent remains 2nd lowest on record to the 18th, 594,000 km² above the lowest year, 2016. The last 5 days have seen substantial gains in Hudson Bay balanced by losses in the Kara sea, causing the centred 5 day mean increase to drop below average.
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

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Re: The 2020/2021 freezing season
« Reply #839 on: November 19, 2020, 03:48:15 PM »
what a retreat on the kara sea!
I wonder how much of that dramatic retreat in the Kara was due to the newly formed ice being melted, and how much was simply crushed into a smaller area by the winds?  Either way, not good, but melting would be more alarming, IMO.
I don't know how much wind/waves and how much melt either, but it is a major reason why total Arctic sea ice extent and area daily gains have slowed down recently.
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Re: The 2020/2021 freezing season
« Reply #840 on: November 19, 2020, 11:45:43 PM »
Is it just me or has the Pacific side / edge of the ice pack been retreating the last three days ?

Darvince

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Re: The 2020/2021 freezing season
« Reply #841 on: November 20, 2020, 03:40:28 AM »
Considering the current SST situation, I expect there to be an unusually long lasting polynya in the ice in the ESS until a record late date, perhaps mid-November or so.
Exactly November 15th is when ice growth filled in the last of the Laptev with ice extent. I guess the 1C-per-week after minimum rule of thumb I was using works very well for areas more secluded from storm activity and currents.

Extending it to other places, the Hudson should be fully frozen over between December 15th to 20th (although this might be sooner since it's so shallow in the areas that are at or above 2C right now), and the Okhotsk should start genuinely forming ice around December 5th.
« Last Edit: November 20, 2020, 03:46:06 AM by Darvince »

Pagophilus

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Re: The 2020/2021 freezing season
« Reply #842 on: November 20, 2020, 12:22:06 PM »
Is it just me or has the Pacific side / edge of the ice pack been retreating the last three days ?
Eyeballing it, the answer for me would be 'yes, slightly'.  Worth watching..
Gerontocrat's replies #1876 and #1884 in the area and extent thread are worth reading in this context.

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Re: The 2020/2021 freezing season
« Reply #843 on: November 20, 2020, 02:04:25 PM »
I still find 2018 the best analogue. We are cca 2 weeks behind:

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Re: The 2020/2021 freezing season
« Reply #844 on: November 20, 2020, 03:08:37 PM »
Is it just me or has the Pacific side / edge of the ice pack been retreating the last three days ?
Eyeballing it, the answer for me would be 'yes, slightly'.  Worth watching..
Gerontocrat's replies #1876 and #1884 in the area and extent thread are worth reading in this context.
Chukchi sea ice extent and area down, just in the last 2 days.
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BornFromTheVoid

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Re: The 2020/2021 freezing season
« Reply #845 on: November 20, 2020, 03:59:03 PM »
A week of NSIDC extent changes
Weekly change is +361,000 km² (81-10 avg: 456,000 km²)
Started 2nd lowest, finished 2nd lowest.
Largest gains in Hudson Bay followed by the Atlantic edge, mixed changes in Baffin and Chukchi Seas, and a large loss in the Kara Sea.

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

Pagophilus

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Re: The 2020/2021 freezing season
« Reply #846 on: November 20, 2020, 07:10:32 PM »
I still find 2018 the best analogue. We are cca 2 weeks behind:

Great illustration of where we are compared to another recent year.

An inexpert take on comparisons:  I think the 2016 refreezing season was so extraordinary that in some ways it has to be filed with the 2012 minimum as waaaay out there, the result of atypical conditions and therefore somewhat unsuitable for general comparisons.  In other words, the second-lowest extent for this year, both now and in September, is dramatic.  Focusing on first place (which I have to fight myself from doing) tends to conceal that.  Comparing the current state of the ice with the 'two weeks ahead' 2018 freezing season is much more revealing IMO.
« Last Edit: November 20, 2020, 07:16:09 PM by Pagophilus »

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Re: The 2020/2021 freezing season
« Reply #847 on: November 20, 2020, 07:34:37 PM »
The ice is still quite thin in most of the siberian arctic.

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Re: The 2020/2021 freezing season
« Reply #848 on: November 20, 2020, 10:08:34 PM »
I still find 2018 the best analogue. We are cca 2 weeks behind:

      1.  That is a great comparison.  Does anybody have an estimate for how much thickness addition is lost for the April maximum by a two week delay in November freezing?

---------------------------------
      2. Late-September to mid-November 2020 DMI 80+N temperatures (first chart) continue to track almost as high as same dates in 2016 (second chart), and similar to but slightly warmer (eyeball estimate) than same dates in 2018 (third chart). 
     
      Will 2020 continue as warm until the end of the year as 2016, or follow the cooler (but still warmer than most years) track of late 2018? 
     
      The fourth chart of GFS 2M temperature anomaly forecast on Climate Reanalyzer suggests that 2020 high Arctic temperatures will continue well above the climatic average for the next 10 days.

      Despite the completely expected period of accelerated Extent and Area gains after the delayed start, late 2020 so far is not providing much indication for a robust compensatory refreeze after the low September minimums.  Refreeze season is just barely over 50% done, so too early to estimate, but from what we have seen so far it is looking like ASI could enter the 2021 melt season in an unusually vulnerable condition from the surface-and-above view.
« Last Edit: November 21, 2020, 05:22:09 AM by Glen Koehler »

Glen Koehler

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Re: The 2020/2021 freezing season
« Reply #849 on: November 21, 2020, 01:42:57 AM »
       Then I look at Polyakov et al. 2020 and start to wonder if all this attention to top-side forcings overlooks the near-surface turbulence with vertical mixing and below-surface halocline/thermocline & heat diffusion transformation that could be where the major forcing is taking place.  It's too bad we don't have equivalent graphical products for tracking and prediction of "ocean weather" (e.g. water temperature, salinity plumes, movement of water masses analogous to air masses, etc.).  Those measures are available, but their presentation is not as highly developed or as routinely presented for layperson consumption as the atmospheric weather products we are used to. 

       My growing suspicion is that like a drunk looking for his keys under the street light, we are focusing our attention where it is easiest to see what's going on.  But to understand the real situation we need to look at a broader range of monitoring tools.  It is often said that the Arctic provides never-ending surprises.  Perhaps our above-surface bias is a contributing factor to our being regularly surprised (says the guy who just posted 4 air temperature charts).

       A-Team, uniquorn and others are posting stuff about the water world perspective.  Much of it is not as easy to summarize for the lay reader (like me) to intuitively understand.  A chart showing a big red blob marking a positive aerial temperature anomaly over the Arctic is easy to understand.  Similar synoptic standardized graphs for the surface and sub-surface water measures would be a useful addition.  Easy for me to say because I'm not going to be the one to do anything about it. 

      I'm just pointing out that 71% of the Earth's surface that interacts with greenhouse gas heat-trapping insulation is water.  That 93% of the added heat energy from global warming is in the water.  That H2O vapor is a stronger greenhouse gas than CO2.  And now, with respect to the ASI, Polyakov and others are quantifying what should have been obvious all along (and probably was to those who study this stuff) that those of us watching the ASI drama need to pay more attention to the water that the ice is floating in and made from if we want to understand what is going on.
« Last Edit: November 21, 2020, 01:57:10 AM by Glen Koehler »