Support the Arctic Sea Ice Forum and Blog

Author Topic: The 2020/2021 freezing season  (Read 94162 times)

Pagophilus

  • Grease ice
  • Posts: 533
    • View Profile
  • Liked: 300
  • Likes Given: 441
Re: The 2020/2021 freezing season
« Reply #150 on: October 01, 2020, 10:31:46 PM »
Much of the Chukchi, ESS and Laptev are still above freezing.
And more broadly, NOAA reports
"The Northern Hemisphere had its warmest summer on record at 1.17°C (2.11°F) above average, surpassing the now second-warmest such period set in 2016 and again in 2019."
https://www.ncdc.noaa.gov/sotc/global/202008
There must be a lot of heat stored in the N Hemisphere oceans generally from this record summer.

Aluminium

  • Grease ice
  • Posts: 767
    • View Profile
  • Liked: 677
  • Likes Given: 391
Re: The 2020/2021 freezing season
« Reply #151 on: October 02, 2020, 05:46:10 AM »
September 27 - October 1.

2019.

BornFromTheVoid

  • Nilas ice
  • Posts: 1250
    • View Profile
  • Liked: 579
  • Likes Given: 199
Re: The 2020/2021 freezing season
« Reply #152 on: October 02, 2020, 12:57:06 PM »
Todays update
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

Freegrass

  • Nilas ice
  • Posts: 1640
  • None but ourselves can free our minds...
    • View Profile
  • Liked: 522
  • Likes Given: 765
Re: The 2020/2021 freezing season
« Reply #153 on: October 02, 2020, 01:34:39 PM »
Latest Five Day Forecast
Wind @ Surface + Total Precipitable Water
Wind + Temp @ 850hPa
Large GiFS!
« Last Edit: October 02, 2020, 01:41:15 PM by Freegrass »
Now let's pray...

If the science don't fit our beliefs, we pray to God and cuddle up in our own delusional fantasy where everything makes sense again...

Sepp

  • New ice
  • Posts: 14
    • View Profile
  • Liked: 12
  • Likes Given: 36
Re: The 2020/2021 freezing season
« Reply #154 on: October 02, 2020, 02:20:08 PM »
The first SMOS thin ice thickness map of this freezing season is released.


SimonF92

  • Frazil ice
  • Posts: 325
    • View Profile
  • Liked: 139
  • Likes Given: 68
Re: The 2020/2021 freezing season
« Reply #155 on: October 02, 2020, 02:32:11 PM »
The first SMOS thin ice thickness map of this freezing season is released.

Thanks for the reminder about SMOS Sepp, last 11 years of Oct1st SMOS
Bunch of small python Arctic Apps:
https://github.com/SimonF92/Arctic

oren

  • Moderator
  • First-year ice
  • Posts: 6421
    • View Profile
  • Liked: 2388
  • Likes Given: 2039
Re: The 2020/2021 freezing season
« Reply #156 on: October 02, 2020, 04:04:40 PM »
Thanks for the SMOS post. As we suspected, all that MYI exported to the Beaufort tail has nearly melted out, and will give no resilience against next year's melting season.

SimonF92

  • Frazil ice
  • Posts: 325
    • View Profile
  • Liked: 139
  • Likes Given: 68
Re: The 2020/2021 freezing season
« Reply #157 on: October 02, 2020, 04:36:40 PM »
Yeah there is barely any there, less than 20%
Bunch of small python Arctic Apps:
https://github.com/SimonF92/Arctic

gandul

  • Grease ice
  • Posts: 764
    • View Profile
  • Liked: 184
  • Likes Given: 10
Re: The 2020/2021 freezing season
« Reply #158 on: October 02, 2020, 05:37:02 PM »
Thanks for the SMOS post. As we suspected, all that MYI exported to the Beaufort tail has nearly melted out, and will give no resilience against next year's melting season.
It effectively amounts to open water except energy to refreeze further area is closer to zero.
For practical purposes Beaufort sea is free of MYI facing the refreeze season

Glen Koehler

  • Frazil ice
  • Posts: 378
    • View Profile
  • Liked: 378
  • Likes Given: 806
Re: The 2020/2021 freezing season
« Reply #159 on: October 02, 2020, 06:58:04 PM »
It makes me think all that ice is going to 'fall off' (break loose from Greenland/CAA/Alaska) and hit me on the head (as an icicle hanging from an eave might [or worse - refrozen half melted snow that partially slipped over the eave's edge before temporarily refreezing in place] ). 

With Greenland (or Canada) at the bottom, all that landmass will hold the ice up forever...
 :)
     To my eye that orientation highlights the fact that much of the remaining ice is at latitude below 80, so presumably more vulnerable to future melt.

BornFromTheVoid

  • Nilas ice
  • Posts: 1250
    • View Profile
  • Liked: 579
  • Likes Given: 199
Re: The 2020/2021 freezing season
« Reply #160 on: October 02, 2020, 07:18:06 PM »
Playing around with some more data viz stuff.
So below is the September sea ice extent persistence. Basically, it's like stacking the average September sea ice extent for every year from 1979 to 2020 on top of each other.
Where sea ice is present in every year, the pixel value is 42 (white in the image).
Where it's present in 20 of the years, it gets a pixel values of 20 (light green)
Where it was only present in one year, it gets a value of 1 (dark orange)
And everything in between!

I'm open to suggestions on how best to display this data. I plan on doing the same for all other months too
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

KenB

  • New ice
  • Posts: 69
    • View Profile
  • Liked: 31
  • Likes Given: 8
Re: The 2020/2021 freezing season
« Reply #161 on: October 02, 2020, 08:13:12 PM »
Playing around with some more data viz stuff.
So below is the September sea ice extent persistence. Basically, it's like stacking the average September sea ice extent for every year from 1979 to 2020 on top of each other.
Where sea ice is present in every year, the pixel value is 42 (white in the image).
Where it's present in 20 of the years, it gets a pixel values of 20 (light green)
Where it was only present in one year, it gets a value of 1 (dark orange)
And everything in between!

I'm open to suggestions on how best to display this data. I plan on doing the same for all other months too

Very nice.  For the low values, it might be nice to have a sense of what years contributed (confirming the presumption that for pixels with values 1,2,3 it's mostly very early years). 

I suppose you could keep the color scheme and use something like transparency?  Count each year as (y - 1978) and sum them up, then normalize for the number of years.  So a pixel with a count of 3 from 79,80,81 would be quite transparent but one from 06,14,18 would be less so?
"When the melt ponds drain apparent compaction goes up because the satellite sees ice, not water in ponds." - FOoW

gerontocrat

  • First-year ice
  • Posts: 9628
    • View Profile
  • Liked: 3809
  • Likes Given: 29
Re: The 2020/2021 freezing season
« Reply #162 on: October 02, 2020, 08:16:32 PM »
Playing around with some more data viz stuff.
So below is the September sea ice extent persistence. Basically, it's like stacking the average September sea ice extent for every year from 1979 to 2020 on top of each other.
Where sea ice is present in every year, the pixel value is 42 (white in the image).
Where it's present in 20 of the years, it gets a pixel values of 20 (light green)
Where it was only present in one year, it gets a value of 1 (dark orange)
And everything in between!
I've done work and graphs on open water. i.e. the absence of ice. If one starts with the objective of showing that the ice is is disappearing, i.e progress towards an ice-free Arctic, then the data is essentially the same, but switched to the frequency of open water years, e.g.

where open water has always been there, pixel value = 42,
where open water has been there for only 10 years pixel value = 10.
where open water has never been there pixel value = 0.

The colour gradient would be the same - blue for open water, sliding through the rainbow to dark red and then finally to white.

A gif of the 12 months would show the waxing and waning of the ice. Another way is to take the 42 images for a particular month and gif that to show the ice retreating and the open water expanding.

Sounds like you are going to have fun.


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

PragmaticAntithesis

  • New ice
  • Posts: 97
    • View Profile
  • Liked: 29
  • Likes Given: 85
Re: The 2020/2021 freezing season
« Reply #163 on: October 02, 2020, 08:18:55 PM »
I'm open to suggestions on how best to display this data. I plan on doing the same for all other months too

This pixel values for 35+ look very similar to the pixel values for open water, so you may want to flip the colour scale upside-down.
A single seed in the right place can sprout an entire forest.

gerontocrat

  • First-year ice
  • Posts: 9628
    • View Profile
  • Liked: 3809
  • Likes Given: 29
Re: The 2020/2021 freezing season
« Reply #164 on: October 02, 2020, 08:31:28 PM »
It makes me think all that ice is going to 'fall off' (break loose from Greenland/CAA/Alaska) and hit me on the head (as an icicle hanging from an eave might [or worse - refrozen half melted snow that partially slipped over the eave's edge before temporarily refreezing in place] ). 

With Greenland (or Canada) at the bottom, all that landmass will hold the ice up forever...
 :)
     To my eye that orientation highlights the fact that much of the remaining ice is at latitude below 80, so presumably more vulnerable to future melt.
And to my eye it tells me that the Russians know that the Arctic ocean belongs to them - might is right. Oh, and economic / military development will accelerate.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

BornFromTheVoid

  • Nilas ice
  • Posts: 1250
    • View Profile
  • Liked: 579
  • Likes Given: 199
Re: The 2020/2021 freezing season
« Reply #165 on: October 02, 2020, 10:25:35 PM »
Cheers for all the suggestions so far, lots of good stuff! I'll post a few more versions tomorrow for critiquing.

I am also working on a map that highlights the year that sea ice last covered a particular area.

Overall, I like the idea of generating a static image that kind of highlights directional and temporal melt momentum - like what parts of the Arctic are retreating towards the N. Pole the fastest, and how has this varied over time. Easy to do via animations, but a bit more tricky for static images.
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

oren

  • Moderator
  • First-year ice
  • Posts: 6421
    • View Profile
  • Liked: 2388
  • Likes Given: 2039
Re: The 2020/2021 freezing season
« Reply #166 on: October 03, 2020, 10:14:10 AM »
BFTV, great visualization. May I make a few suggestions:
* As headline numbers have been "fake stable" since 2007, I suggest to do another version, of 2007-2020 only.
* As monthly averages often hide interesting details, I suggest to do it with daily data.
* As the end of September contains a lot of new thin ice, I suggest to do this with data for the 1st-10th of September only. This will give the probability of an ice cover close to the minimum in recent years.
* So the map would be made up of 14 years x 10 days each, and maximal rating would be 140.
* I still think the highest rank ("never had open water") should be white and all the rest a graded color scale.

* While I'm at it, it would be quite interesting to have the same visualization for other seasonal periods, for example 1-10th of August, of July, June. Each of these will answer a different question but in the same effective method. And it fits with A-Tean's discussion of early open water and its effects.

As a comparison, make another 1-10th Sep map for 1979-1992, before the ice began its serious decline. The two maps side by side will tell the story of the change that took place in the Arctic, and how some regions with perrenial ice cover became seasonally ice free, statistically speaking.

I realize what I wrote above is a load of work. Words are easy... but I appreciate any analysis you can provide along these lines. I have long dreamed of making these myself, but my graphic and netcdf skills are very poor unfortunately.

BornFromTheVoid

  • Nilas ice
  • Posts: 1250
    • View Profile
  • Liked: 579
  • Likes Given: 199
Re: The 2020/2021 freezing season
« Reply #167 on: October 03, 2020, 11:58:35 AM »
Good suggestions Oren. I'll work on some of those during the coming week as I get the time.

Here's today images and animation. A flash filling in of the Chukchi bite, curious to see if it persists.
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

Freegrass

  • Nilas ice
  • Posts: 1640
  • None but ourselves can free our minds...
    • View Profile
  • Liked: 522
  • Likes Given: 765
Re: The 2020/2021 freezing season
« Reply #168 on: October 03, 2020, 10:22:47 PM »
Latest Five Day Forecast
Wind + Temp @ Surface
Large GiF!
Now let's pray...

If the science don't fit our beliefs, we pray to God and cuddle up in our own delusional fantasy where everything makes sense again...

VeliAlbertKallio

  • Frazil ice
  • Posts: 205
  • Eheu fugaces labuntur anni
    • View Profile
    • Sea Research Society (SRS)
  • Liked: 86
  • Likes Given: 113
Re: The 2020/2021 freezing season
« Reply #169 on: October 04, 2020, 01:38:45 AM »
There are also satellite sea ice maps now available for September 1-10 dates since 1964. Walt Meier can provide these 1960's to 1970's recovered from earlier satellite data with NASA.

BFTV, great visualization. May I make a few suggestions:
* As headline numbers have been "fake stable" since 2007, I suggest to do another version, of 2007-2020 only.
* As monthly averages often hide interesting details, I suggest to do it with daily data.
* As the end of September contains a lot of new thin ice, I suggest to do this with data for the 1st-10th of September only. This will give the probability of an ice cover close to the minimum in recent years.
* So the map would be made up of 14 years x 10 days each, and maximal rating would be 140.
* I still think the highest rank ("never had open water") should be white and all the rest a graded color scale.

* While I'm at it, it would be quite interesting to have the same visualization for other seasonal periods, for example 1-10th of August, of July, June. Each of these will answer a different question but in the same effective method. And it fits with A-Tean's discussion of early open water and its effects.

As a comparison, make another 1-10th Sep map for 1979-1992, before the ice began its serious decline. The two maps side by side will tell the story of the change that took place in the Arctic, and how some regions with perrenial ice cover became seasonally ice free, statistically speaking.

I realize what I wrote above is a load of work. Words are easy... but I appreciate any analysis you can provide along these lines. I have long dreamed of making these myself, but my graphic and netcdf skills are very poor unfortunately.
"Setting off atomic bombs is considered socially pungent as the years are made of fleeting ice that are painted by the piling up of the rays of the sun."

BornFromTheVoid

  • Nilas ice
  • Posts: 1250
    • View Profile
  • Liked: 579
  • Likes Given: 199
Re: The 2020/2021 freezing season
« Reply #170 on: October 04, 2020, 02:02:41 AM »
Nice suggestions VAC. I'll try to get my hands on those maps.

Been up late dealing with reddit moderating drama, and playing about with some suggestions made previously.

As a start, here's the ice persistence map, and another highlighting the last year ice was present, for just the single day minima from 1979 to 1989.

I'll continue to adjust the colours, add more months/years/decades and try out other suggestions in the coming days too.
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

Aluminium

  • Grease ice
  • Posts: 767
    • View Profile
  • Liked: 677
  • Likes Given: 391
Re: The 2020/2021 freezing season
« Reply #171 on: October 04, 2020, 07:38:03 AM »
September 29 - October 3.

2019.

Niall Dollard

  • Grease ice
  • Posts: 769
    • View Profile
  • Liked: 299
  • Likes Given: 75
Re: The 2020/2021 freezing season
« Reply #172 on: October 04, 2020, 10:20:54 AM »
Freezing progress is so slow. In rugby parlance, these are the hard yards.

Not sure if it is thick enough to count yet but from Aluminum's video it looks like a good bit at the northern Beaufort is turning blue.

BornFromTheVoid

  • Nilas ice
  • Posts: 1250
    • View Profile
  • Liked: 579
  • Likes Given: 199
Re: The 2020/2021 freezing season
« Reply #173 on: October 04, 2020, 12:47:33 PM »
Images and animation for today
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

Freegrass

  • Nilas ice
  • Posts: 1640
  • None but ourselves can free our minds...
    • View Profile
  • Liked: 522
  • Likes Given: 765
Re: The 2020/2021 freezing season
« Reply #174 on: October 04, 2020, 03:23:15 PM »
Latest Five Day Forecast
Wind + Temp @ 850hPa
Large Gif!
Now let's pray...

If the science don't fit our beliefs, we pray to God and cuddle up in our own delusional fantasy where everything makes sense again...

Positive retroaction

  • New ice
  • Posts: 50
    • View Profile
  • Liked: 28
  • Likes Given: 148
Re: The 2020/2021 freezing season
« Reply #175 on: October 04, 2020, 07:26:35 PM »
Thank you, I follow this topic with enthusiasm
Would it be interesting to have the animation of the average extension of the last years (or a still image) to see the freezing speed of 2020 compared to other years? Maybe with an average day by day of extent progression?
Sorry, excuse my bad english

BornFromTheVoid

  • Nilas ice
  • Posts: 1250
    • View Profile
  • Liked: 579
  • Likes Given: 199
Re: The 2020/2021 freezing season
« Reply #176 on: October 04, 2020, 10:32:52 PM »
Here are the sea ice minimum extent persistence, based on the single day minimum values.
They are split, roughly, by decade.
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

BornFromTheVoid

  • Nilas ice
  • Posts: 1250
    • View Profile
  • Liked: 579
  • Likes Given: 199
Re: The 2020/2021 freezing season
« Reply #177 on: October 04, 2020, 10:35:23 PM »
The same as above, but split based on the dates mentioned by Oren.
So we've 1979-1992, 1993-2006 and 2007-2020.
And a final one with all of the years.

I'll work on actually doing some actual analysis of these later in the week when I've some more time.

EDIT: Just spotted a mistake in the final image... just a sec Fixed! Though the images may be in the wrong order now. Oh well.
« Last Edit: October 04, 2020, 10:41:55 PM by BornFromTheVoid »
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

Tor Bejnar

  • Young ice
  • Posts: 3724
    • View Profile
  • Liked: 653
  • Likes Given: 440
Re: The 2020/2021 freezing season
« Reply #178 on: October 04, 2020, 11:11:45 PM »
I thought you 'should' include 2020 in the last frame.  (You obviously read my mind ;))  After all, you included 1979 in the first one.  A GIF of the four frames might show the evolution very nicely.
Arctic ice is healthy for children and other living things.

oren

  • Moderator
  • First-year ice
  • Posts: 6421
    • View Profile
  • Liked: 2388
  • Likes Given: 2039
Re: The 2020/2021 freezing season
« Reply #179 on: October 04, 2020, 11:24:39 PM »
Thank you so much BFTV, super-amazing. I will examine these images in more detail later, a lot to be found in there.
« Last Edit: October 06, 2020, 06:23:08 AM by oren »

grixm

  • Frazil ice
  • Posts: 349
    • View Profile
  • Liked: 209
  • Likes Given: 68
Re: The 2020/2021 freezing season
« Reply #180 on: October 05, 2020, 12:37:03 PM »
Not sure if this is autocorrelated with the current low extent but the temperature anomaly forecast in the arctic and especially siberian seas is extreme, hovering around +15C.
Keep in mind the image below is the forecasted 10-day average. Usually you'd see quite low anomalies on such a map because such long term forecasts tend to go up and down and thus even out the average. But now the forecast just stays red hot in the ESS and Laptev for the entire 10-day period without pause.

Paddy

  • Grease ice
  • Posts: 710
    • View Profile
  • Liked: 66
  • Likes Given: 81
Re: The 2020/2021 freezing season
« Reply #181 on: October 05, 2020, 12:44:09 PM »
Not sure if this is autocorrelated with the current low extent but the temperature anomaly forecast in the arctic and especially siberian seas is extreme, hovering around +15C.
Keep in mind the image below is the forecasted 10-day average. Usually you'd see quite low anomalies on such a map because such long term forecasts tend to go up and down and thus even out the average. But now the forecast just stays red hot in the ESS and Laptev for the entire 10-day period without pause.

Combined with how high the anomaly has been so far this freezing season (looking at dmi80N http://ocean.dmi.dk/arctic/meant80n.uk.php), you'd anticipate that ice will not be forming anything like as much as it should.

Freegrass

  • Nilas ice
  • Posts: 1640
  • None but ourselves can free our minds...
    • View Profile
  • Liked: 522
  • Likes Given: 765
Re: The 2020/2021 freezing season
« Reply #182 on: October 05, 2020, 01:06:37 PM »
Latest Five Day Forecast
Wind + Temp @ Surface
Large GiF!
Now let's pray...

If the science don't fit our beliefs, we pray to God and cuddle up in our own delusional fantasy where everything makes sense again...

Pagophilus

  • Grease ice
  • Posts: 533
    • View Profile
  • Liked: 300
  • Likes Given: 441
Re: The 2020/2021 freezing season
« Reply #183 on: October 05, 2020, 01:21:06 PM »
Not sure if this is autocorrelated with the current low extent but the temperature anomaly forecast in the arctic and especially siberian seas is extreme, hovering around +15C.
Keep in mind the image below is the forecasted 10-day average. Usually you'd see quite low anomalies on such a map because such long term forecasts tend to go up and down and thus even out the average. But now the forecast just stays red hot in the ESS and Laptev for the entire 10-day period without pause.
A disturbing forecast (and while it is only a forecast, these forecasts are our only way of looking forward for the atmosphere).  Worth mentioning too is the lack of negative forecast anomalies for this period elsewhere in the Arctic, except in the CAA to some extent.  Given the heat stored in the Arctic seas around the main pack and the probable disturbances to and weakening of the halocline, what is there to argue against a slowing of the growth of ice extent (relative to most other years) over the next two weeks?  Such a slowing also happened in 2019, 2018 and 2016 around this time (although I have no idea why extent growth slowed in those three years).
« Last Edit: October 05, 2020, 06:36:08 PM by Pagophilus »

gandul

  • Grease ice
  • Posts: 764
    • View Profile
  • Liked: 184
  • Likes Given: 10
Re: The 2020/2021 freezing season
« Reply #184 on: October 05, 2020, 01:27:47 PM »
Not sure if this is autocorrelated with the current low extent but the temperature anomaly forecast in the arctic and especially siberian seas is extreme, hovering around +15C.
Keep in mind the image below is the forecasted 10-day average. Usually you'd see quite low anomalies on such a map because such long term forecasts tend to go up and down and thus even out the average. But now the forecast just stays red hot in the ESS and Laptev for the entire 10-day period without pause.
Laptev-ESS seas venting out their energy excess?

I would expect an acceleration of refreezing around the pack this week in view of Freegrass animations, but it is difficult to say.

colchonero

  • Frazil ice
  • Posts: 129
    • View Profile
  • Liked: 24
  • Likes Given: 5
Re: The 2020/2021 freezing season
« Reply #185 on: October 05, 2020, 01:38:35 PM »
Not sure if this is autocorrelated with the current low extent but the temperature anomaly forecast in the arctic and especially siberian seas is extreme, hovering around +15C.
Keep in mind the image below is the forecasted 10-day average. Usually you'd see quite low anomalies on such a map because such long term forecasts tend to go up and down and thus even out the average. But now the forecast just stays red hot in the ESS and Laptev for the entire 10-day period without pause.

Yup, and it will continue to be like that, as long as there is no ice formed. As long as there is open water, we won't see normal temperatyre at those locations, because surface temperature can't drop that much with open water instead of ice beneath, even if we would actually have "good" forecast(negative temp850hPa anomalies or neutral), with stable vortex and no heat from lower latitudes.  So those anomalies will remain intact for a while.

SimonF92

  • Frazil ice
  • Posts: 325
    • View Profile
  • Liked: 139
  • Likes Given: 68
Re: The 2020/2021 freezing season
« Reply #186 on: October 05, 2020, 01:48:12 PM »
If the Arctic is the centre of climate change then Laptev/ ESS are rapidly becoming the centre of centre
Bunch of small python Arctic Apps:
https://github.com/SimonF92/Arctic

BornFromTheVoid

  • Nilas ice
  • Posts: 1250
    • View Profile
  • Liked: 579
  • Likes Given: 199
Re: The 2020/2021 freezing season
« Reply #187 on: October 05, 2020, 01:52:13 PM »
Today's images and animation
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

RoxTheGeologist

  • Grease ice
  • Posts: 523
    • View Profile
  • Liked: 157
  • Likes Given: 126
Re: The 2020/2021 freezing season
« Reply #188 on: October 05, 2020, 07:26:42 PM »
Quote from: gandul link=topic=3299.msg288918#msg288918

....Laptev-ESS seas venting out their energy excess?


Right - that is my guess. No insulating ice to allow the temperature to drop.
« Last Edit: October 05, 2020, 11:02:06 PM by RoxTheGeologist »

Stephan

  • Nilas ice
  • Posts: 1412
    • View Profile
  • Liked: 504
  • Likes Given: 243
Re: The 2020/2021 freezing season
« Reply #189 on: October 05, 2020, 08:53:59 PM »
Latest Five Day Forecast
Wind + Temp @ Surface
Large GiF!
A closer look onto ESS/Laptev on the one hand and the Barents on the other shows mostly southerly winds in both areas. This should slow down cooling at least a little bit, even if Siberia turned into "blue".
It is too late just to be concerned about Climate Change

Aluminium

  • Grease ice
  • Posts: 767
    • View Profile
  • Liked: 677
  • Likes Given: 391
Re: The 2020/2021 freezing season
« Reply #190 on: October 06, 2020, 10:20:41 AM »
October 1-5.

2019.

aslan

  • Frazil ice
  • Posts: 214
    • View Profile
  • Liked: 168
  • Likes Given: 0
Re: The 2020/2021 freezing season
« Reply #191 on: October 06, 2020, 11:59:06 AM »
Not sure if this is autocorrelated with the current low extent but the temperature anomaly forecast in the arctic and especially siberian seas is extreme, hovering around +15C.
Keep in mind the image below is the forecasted 10-day average. Usually you'd see quite low anomalies on such a map because such long term forecasts tend to go up and down and thus even out the average. But now the forecast just stays red hot in the ESS and Laptev for the entire 10-day period without pause.
Laptev-ESS seas venting out their energy excess?

I would expect an acceleration of refreezing around the pack this week in view of Freegrass animations, but it is difficult to say.

I doubt it. There is still a massive amount of oceanic heat and it is still looking like the halocline has taken a hit. And massive heat wave is still ongoing, no matter the temperature at 850 hPa. And this is not only a matter of absolute magnitude of the anomaly. October is probably going to be less extreme than September from a certain point of view. I mean, in term of deviation to the norm, the month of September was probably the most extreme month ever recorded anywhere on earth, no exaggeration. Ostrov Golomyanyj (data since the 30s...) has broken its monthly mean temperature by 3.3°C ! Ostrov Vize by 1.6°C after breaking the monthly record of august by 2.3. Same idea for Kotel'nyj, Izvestij Tsik, Dikson, Heiss (Polargmo), Hatanga etc... As an illustration, September mean temperature for Ostrov Kotel'nyj (WMO 21432). I have never heard of a heat wave so extreme over a two month period, and this is over an area of 2 millions of km² or something like that. Even though October will be extremely warm, such deviation is not likely in October (hopefully…). But in any case, there is really something ongoing on the Atlantic side. It will take more than a week of seasonal cooling for resorbing these anomalies.
« Last Edit: October 06, 2020, 01:27:18 PM by aslan »

aslan

  • Frazil ice
  • Posts: 214
    • View Profile
  • Liked: 168
  • Likes Given: 0
Re: The 2020/2021 freezing season
« Reply #192 on: October 06, 2020, 12:41:40 PM »
To illustrate, a set of graph for the period August - Septemeber. Record for Gmo Im. E. K. Federova, breaking its record by 2.2°C (cap Tcheliouskine),or 3.5 sigma above the most recent 30 years mean... And there is ~ 1500 km between Heiss (Polargmo or wmo 20046) and Hatanga (20891), which squared is ~ 2 millions km²
« Last Edit: October 06, 2020, 01:27:27 PM by aslan »

binntho

  • Nilas ice
  • Posts: 1534
    • View Profile
  • Liked: 544
  • Likes Given: 122
Re: The 2020/2021 freezing season
« Reply #193 on: October 06, 2020, 12:49:41 PM »
aslan you're right these are truly amazing spikes. There is no denying that the Arctic is changing much faster than we expected.
because a thing is eloquently expressed it should not be taken to be as necessarily true
St. Augustine, Confessions V, 6

BornFromTheVoid

  • Nilas ice
  • Posts: 1250
    • View Profile
  • Liked: 579
  • Likes Given: 199
Re: The 2020/2021 freezing season
« Reply #194 on: October 06, 2020, 02:32:34 PM »
Images and animation for today.

Btw, I'm going to start making these updates roughly twice per week after this
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

SimonF92

  • Frazil ice
  • Posts: 325
    • View Profile
  • Liked: 139
  • Likes Given: 68
Re: The 2020/2021 freezing season
« Reply #195 on: October 06, 2020, 03:00:08 PM »
Haven't run this script for a while
Bunch of small python Arctic Apps:
https://github.com/SimonF92/Arctic

SimonF92

  • Frazil ice
  • Posts: 325
    • View Profile
  • Liked: 139
  • Likes Given: 68
Re: The 2020/2021 freezing season
« Reply #196 on: October 06, 2020, 04:17:49 PM »
Updated code to provide continuous extent change as opposed to categorical
Bunch of small python Arctic Apps:
https://github.com/SimonF92/Arctic

aslan

  • Frazil ice
  • Posts: 214
    • View Profile
  • Liked: 168
  • Likes Given: 0
Re: The 2020/2021 freezing season
« Reply #197 on: October 06, 2020, 06:15:49 PM »
aslan you're right these are truly amazing spikes. There is no denying that the Arctic is changing much faster than we expected.

It could also be noted that mean wind speed was a bit above average for this corner of Arctic in September. Excepted for Ostrov Heiss, which was near average with mean wind speed of 5.8 m/s, normal 6.0 m/s. For Ostrov Vize, 7 m/s versus 6.5 m/s, for Ostrov Golomyanyj it was 7.25 m/s for a normal of 5.7 m/s, for cape Chelyuskin 6.4 m/s versus 5.8 m/s, etc. It is not particulary noteworthy. But given the magnitude of the anomlies for latent and sensible heat, this is not helping at all. The amount of heat mixed during this month of Septemebr is crazy.

uniquorn

  • Young ice
  • Posts: 2827
    • View Profile
  • Liked: 1288
  • Likes Given: 258
Re: The 2020/2021 freezing season
« Reply #198 on: October 07, 2020, 12:48:31 AM »
There is still a massive amount of oceanic heat
Agreed.
amsr2, awi dev v103 overlaid onto mercator 0m ocean temperature, sep4-oct5
« Last Edit: October 07, 2020, 01:02:08 AM by uniquorn »

Pagophilus

  • Grease ice
  • Posts: 533
    • View Profile
  • Liked: 300
  • Likes Given: 441
Re: The 2020/2021 freezing season
« Reply #199 on: October 07, 2020, 04:41:35 AM »
Oct 4 2020 sea ice extent compared with same date for 2012, 2016, 2019.
Interesting how late the W CAA was still open water in 2012 vs the other years.

http://nsidc.org/arcticseaicenews/sea-ice-comparison-tool/