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Snow & Ice coverage in the Northern Hemisphere Winter 2020/21


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Siberian snow at last. Looks like an area larger than the UK just got dumped on  

Noticed we didn't have Snow & Ice thread yet for this year, one of my favourites of the year. So here's the latest offering:  

Well, well, well.... Checked out US NIC early, as I am out in the morning....  Snow cover -    small reductions in both East and West. But Its an absolute killer for ice extent.....

Posted Images

Masie update for today...

Total extent is 5456K Km2 still  in lowest position.  230K Km2 below last years figures. The total increase for today is +88K, 

Area updates for today -

Beaufort (+6K) now solidly attached to Alaska. Chukchi has taken up the mantle with a 24K Km2 increase. 

ESS and Laptev lost (-1K) apiece,but still cling on to their coastal sea ice.  Elsewhere there were gains in Kara(+7K), Greenland(+2K) and Baffin(+5K). CAA  gained(+29K) while the Central Basin also gained (+16K).

It is also worth noting that the Kara gains were around Russian coastline opposite to the Novaya Zemlya Islands, This ice looks unusual however and may be an error.

Ice is now however showing around the Jan Mayen and Severna Zemlya Islands (for the first time this season), as the main ice pack approaches from the north east.

Also worth noting that ice has appeared off the east coast of Svalbard in Barents - but only a  little ice has registered there yet, 

Volume on DMI continues to track 2019.

 

May I humbly  point out for newcomers that this is a not a climate change thread. I feel that some of the new discussions have been distracting from the actual aims of this thread, which is to document the actual winter snow and ice coverage in the NH.

There is another thread in the Climate Change section entitled 'The Arctic Refreeze', where climate change opinions can be documented and also  be discussed - As has happened in the last few winters.

This thread was set up to document the growth (and its demise) of both the sea ice and snow cover the Northern Hemisphere during the winter season.

MIA

 

 

Edited by Midlands Ice Age
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Early(?) morning update..

Snow has continued to expand in the NH generally, and is now above average for the date.

Ice has decreased slightly (compaction again?) in Chukchi and Beaufort, but has increased pretty well everywhere else.

This includes a mini flash freeze in Laptev along the Russian coastline,

Also my call of a possible 'anoprop' yesterday,  on the Kara coastline appeared to have been incorrect,  as the ice has expanded generally in the what my map calls the River Ob delta area.

Back later with the Masie details, and a review of the next weeks weather in the NH from GFS (via Climate Reanalyser).

Of possible  interest - the charts I posted a week ago for the Arctic weather forecasts have proved almost spot on. It has encouraged me to look at the next weeks charts. 

cursnow_asiaeurope.thumb.gif.38ca6b77ccf7b3e85c9ec1e89d3ce1c0.gif

 

MIA

        

Edited by Midlands Ice Age
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Have we seen an accelerated increase this October compared to the past few........

so many studies into October snowcover  growth - we have seen above average growth in most October’s but perhaps the speed of growth is more significant ???

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7 minutes ago, bluearmy said:

Have we seen an accelerated increase this October compared to the past few........

so many studies into October snowcover  growth - we have seen above average growth in most October’s but perhaps the speed of growth is more significant ???

I think we have, blue, especially since 2012... But, with all that open water, is it really all that surprising?🤔

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As discussed above....  (my note)

I will look at the snow increase charts later as I have to go out now. 

Temperatures have now fallen as the low pressure areas along the Russian coastline have indeed moved South westwards and an anticyclone has now formed over Svalbard as an extension to the heights over Greenland.

This has resulted in the strong eastward based jet-stream in the east of the Arctic (last week) being diverted. This should now enable the ice to form rapidly along the Russian coastline sea areas.  To me it looks as if this has delayed the ice formation there by about one week compared to last year.  (but we will see). 

The following are the 3dayForecast charts (again SLP, Min and average )

 

Today (24/10/2020)                                       

image.thumb.png.973b986d2fa05b386106c4ee4dbbbba0.pngimage.thumb.png.d587be4586a50efcbfb2fc78578edb4d.pngimage.thumb.png.cd5710c7c6204e3d6ff66b17c31a93e1.png     

 

The 3Day Forecast -

             

 image.thumb.png.ff52be805de27278b9d10b85f4651ec4.pngimage.thumb.png.2a0bc7dae15976afeeab7e8e6d9c621b.pngimage.thumb.png.1011b82630cac8ffd5886477df03b570.png

 

 and the 10day Outlook -

image.thumb.png.dc1c2dc706d99e3f816acd0cf2802282.pngimage.thumb.png.d35b0615342a881a70ef916761e54330.pngimage.thumb.png.670f10d11c33a72b02d4bcef8ffa4133.png 

 

As can be seen the -30C are spreading rapidly through out the region as the low pressure anomaly over Russia is replaced by a high pressure. The forecast is for a slack pressure gradient over the Arctic. The low pressure 'string' over Northern Russia is now moving west to take over its traditional seat over the Atlantic.  Most notable is  the  low pressure  area to the west of the UK!!😒

Snowfall levels look as though they may subside back to more normal levels,  but ice looks ready for a return. 

MIA

 

  

Edited by Midlands Ice Age
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A week of slow ice change, shown by a slow animation

AnimationSmall.thumb.gif.4de2d8d1626dae24b0bf0b23b8b44774.gif

ADS/JAXA extent now lowest on record by 631k. If extent/area doesn't start increasing by well over 100k/day from now on, we'll be lowest on record by close to 1 million km2 early next week.

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Blue 

3 hours ago, bluearmy said:

Have we seen an accelerated increase this October compared to the past few........

so many studies into October snowcover  growth - we have seen above average growth in most October’s but perhaps the speed of growth is more significant ???

I have looked into Rutgers.

It shows (at this stage) a pretty impressive growth this year for Eurasia.

File of the weekly values below, but they seem to be running about 10 days behind. 

https://climate.rutgers.edu/snowcover/files/wkcov.eurasia.txt

 

which is about up to 10/10/2020.

It shows an impressive increase (Over 100%) in the first full week of October.

Looking at the current days anomalies, they are now pretty impressive, with gains in most areas..

https://climate.rutgers.edu/snowcover/chart_daily.php?ui_year=2020&ui_day=297&ui_set=2

MIA

 

 

 

  

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2 hours ago, Midlands Ice Age said:

Blue....

  

I have looked into Rutgers.

It shows (at this stage) a pretty impressive growth this year for Eurasia.

File of the weekly values below, but they seem to be running about 10 days behind. 

https://climate.rutgers.edu/snowcover/files/wkcov.eurasia.txt

 

which is about up to 10/10/2020.

It shows an impressive increase (Over 100%) in the first full week of October.

Looking at the current days anomalies, they are now pretty impressive, with gains in most areas..

https://climate.rutgers.edu/snowcover/chart_daily.php?ui_year=2020&ui_day=297&ui_set=2

MIA

 

 

 

  

 

continued....

First of all a correction (Too late to edit), my 100 percent increase for the ice in the first week should have said a more impressive 1000 per cent!!!!  

However compare the link below (which is for the 1st October 2020) to todays date above...

https://climate.rutgers.edu/snowcover/chart_daily.php?ui_year=2020&ui_day=275&ui_set=2

The difference is amazing...

It must qualify as one of the fastest snow growth seasons ever.

Lets hope it performs according to the description on the can (Or the way predictors hope!)

MIA

 

 

Edited by Midlands Ice Age
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Masie (sea ice) report for today..

Total extent 5546K Km2 an increase of 85K Km2 - still in last position, now well behind 2019.

Area changes reflect a total change in weather conditions -

Beaufort (-6K) and Chukchi (-14K) both lost extent after several days of gains.

However the running is now being taken over by the Russian seas,  (about the time I forecast last week)

ESS gained (+10K), Laptev(+24K), and Kara(+24K) all grew rapidly along the coastlines, and look ready to now reach out to the inner islands. Barents, however, did not change.

Greenland(+3K) and Baffin(+11K)  performed to average for the time of year, whilst CAA added (+14K).

CAB(Central) added (+18K)....   mainly in added ice towards the Jan Mayen and Severna Novaya islands, which  look ready to join the main arctic ice pack in the next few days.

For interest DMI shows that the Russian/Siberian waters are in about the same position (re ice growth) that we were in on about the 19th October 2019. By the end of October they were more or less covered in thin ice. Let us see how we compare this year. 

image.thumb.png.8f9d641d707bf90a97f2bd5d110b4697.png      image.thumb.png.d64dcc4da456e2cc14f3f5e8d8ae8492.png

 

Overall the outlook for the ice looks ripe for some sort of fast rebound, as there is a lot of the siberian/russian waters now ready to freeze out.

MIA 

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1 hour ago, Midlands Ice Age said:

 

continued....

First of all a correction (Too late to edit), my 100 percent increase for the ice in the first week should have said a more impressive 1000 per cent!!!!  

However compare the link below (which is for the 1st October 2020) to todays date above...

https://climate.rutgers.edu/snowcover/chart_daily.php?ui_year=2020&ui_day=275&ui_set=2

The difference is amazing...

It must qualify as one of the fastest snow growth seasons ever.

Lets hope it performs according to the description on the can (Or the way predictors hope!)

MIA

we can but hope MIA - is it the rate of change that’s more relevant than the actual coverage ......

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4 hours ago, Midlands Ice Age said:

Masie (sea ice) report for today..

Total extent 5546K Km2 an increase of 85K Km2 - still in last position, now well behind 2019.

Area changes reflect a total change in weather conditions -

Beaufort (-6K) and Chukchi (-14K) both lost extent after several days of gains.

However the running is now being taken over by the Russian seas,  (about the time I forecast last week)

ESS gained (+10K), Laptev(+24K), and Kara(+24K) all grew rapidly along the coastlines, and look ready to now reach out to the inner islands. Barents, however, did not change.

Greenland(+3K) and Baffin(+11K)  performed to average for the time of year, whilst CAA added (+14K).

CAB(Central) added (+18K)....   mainly in added ice towards the Jan Mayen and Severna Novaya islands, which  look ready to join the main arctic ice pack in the next few days.

For interest DMI shows that the Russian/Siberian waters are in about the same position (re ice growth) that we were in on about the 19th October 2019. By the end of October they were more or less covered in thin ice. Let us see how we compare this year. 

image.thumb.png.8f9d641d707bf90a97f2bd5d110b4697.png      image.thumb.png.d64dcc4da456e2cc14f3f5e8d8ae8492.png

 

Overall the outlook for the ice looks ripe for some sort of fast rebound, as there is a lot of the siberian/russian waters now ready to freeze out.

MIA 

I think we are a fair chunk away from 2019-

Maybe the net difference is the current SSTa in that region > at a guess 2-4c warmer than last year

Cant add a pic. Not sure why- useless new forum format.

 

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1 hour ago, Steve Murr said:

I think we are a fair chunk away from 2019-

Maybe the net difference is the current SSTa in that region > at a guess 2-4c warmer than last year

Cant add a pic. Not sure why- useless new forum format.

 

Steve..

I have included the SST's for today from Climate Reanalyser -

image.thumb.png.c8702eca3345bd865928663616a77d38.png

As you can see the vast majority of the Arctic is shown at 0C, so I doubt that it is about 2 - 4C warmer now, even though ice refreezes at -1.8C. I cannot find a similar SST graph for this time last year. I am fairly certain it was posted on here though.

Last year the same comments were being made...

 

 I reported yesterday that we were 230k Km2 below 2019, according to Masie.. 

There is an increased difference in extent certainly, but this increased difference is caused by  the very rapid refreeze  (see above) between 20/10 and 1/11 that happened last year. This happened when, last year.  we were making similar remarks in here, about the fact that the Russian side had failed to refreeze!. It looks like it is becoming a feature of our arctic refreeze.

I am expecting a similar rise in ice extent this week to come,  so it will be  interesting to look at the comparison in a weeks time. (around 1st Nov?), as the ice is about 1week behind last year.  My guess?  We  should then be able to see a true comparison.

Do not forget that  the central pack is much thicker this year, and that means there is, as yet, little difference in the volume figures, despite the lack of extent. We could easily end up with increased volume.

This year has definitely struggled. The anticyclone with clear skies during peak insolation in June and early July, the mini cyclone of August when the ice was very mobile, together with the last weeks easterly gales sweeping less cold air across the refreeze zone,, have all occurred at key (bad) times for the ice.

Will we get similar conditions again in the next few years, or is this the start of a new trend associated with the climatic changes? Only time will tell.

I believe it is still too early yet to write off this refreeze season.

IMO It will depend upon the weather over the next few weeks..

MIA

Edited by Midlands Ice Age
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11 hours ago, Midlands Ice Age said:

 

I am expecting a similar rise in ice extent this week to come,  so it will be  interesting to look at the comparison in a weeks time. (around 1st Nov?), as the ice is about 1week behind last year.  My guess? 

 

MIA

Well it looks as though spot on the predicted time the ice is expanding very rapidly along the Russian coastline.

Already JAXA has recorded a century+ growth. Masie to follow later...

Snow cover reduced in Siberia from the south and west. Still strong growth in N.A. though. 

Ice seems to be playing catchup in all areas, except Beaufort. USnic below

image.thumb.png.ec0b6f1384a384bca1b8017b4588557c.pngimage.thumb.png.200e8f9568d751ee9bcc4107935df11b.png     

 

MIA

 

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Sorry MIA I could post an image in my original reply.

So all rolled back into 1 post.

The siberian ice anomaly V 2019 is pretty sizeable

54F7313A-1860-4D08-8CC3-1CA11BA7FC1F.thumb.jpeg.498559c07922ed588a54e8f509f4cf31.jpeg

 

So not sure how you compare when your comparing apples with oranges.

Also I mentioned SSTa but I didnt include the fact that the ice growth is dependent on not only the SST at the top & the T2M air just above it but also the column of water to around 30M below- There was a nice image on crypsphere forum.

However you didnt provide any evidence of the sstas over Siberia > just an opinion.

We heres the data as said net 2-4C.

ACAFD095-157B-43C0-B327-C213754D2973.thumb.jpeg.2974ca146d6a40cc5aea2b030b175dba.jpeg

The reason there are is slush build up on the coast is because its a very shallow shelf so this area responds quickly to the lower surface air temperature- hence the freeze now.

09DB68A0-83FB-4D4A-9F8C-0EA52697986C.thumb.jpeg.5fcbec2c16d9208c0f604e8b83f8215b.jpeg

However out past the shelf thats deeper - the column of water to 30M is showing considerable anomalous warmth V the norm ( probably related to the longer exposure to sun in the summer )

The net fallout here is its going to take longer than usual to cool that deep layer to a point where is freezes-

I would be suggesting that if you are comparing 2019 > 2020 then 2-3 weeks will be the differnce to get to a full cover..

Im sure if we look in the archives there will be a date that this occurs both on ave in the 2010s as well as 2019 in isolation...

This will also have a net negative impact on the siberian ice cover & melt out date for 2021 > most likely earlier still...

S

 

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So just to add heres the date the siberian ice was all covered last year courtesy of the post below

November 4th.BE218743-5D9E-4247-AA1E-FE513CF46D91.thumb.jpeg.8b34b96cd19a75529a1d000c4bfa660d.jpeg

 

Based on that I will go with the 15th-18th of November this year 2 weeks later.

2019 was the latest on record for the Siberian ice..

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5760.jpg?width=1200&height=630&quality=8
WWW.GOOGLE.COM

Delayed freeze in Laptev Sea could have knock-on effects across polar region, scientists say

For the first time since records began, the main nursery of Arctic sea ice in Siberia has yet to start freezing in late October.

The delayed annual freeze in the Laptev Sea has been caused by freakishly protracted warmth in northern Russia and the intrusion of Atlantic waters, say climate scientists who warn of possible knock-on effects across the polar region.

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Well... well....!!!

Re the above.

I can only report what I can see in the numbers.I am consistent with the data thru' bad and good times for he sea ice.  I do not report only when things are doing well (or not,  as the case may be)..  

 

Masie sea ice extent  5860K Km2  a total gain of +319K Km2. However it is still at a lowest for the date.

Gains were seen pretty well through all the sea areas, (though the Laptev and Kara were extreme), apart from the exception of Beaufort (+0) and Chukchi(+5K). These 2 areas have not been as deficient in the ice growth in the last month, and the winds seem to have pushed the ice out to sea again in Beaufort.

ESS gained (+24K), Laptev(+58K) and the big winner for today>>>,  Kara which gained (+62K)

There was even growth recorded in Barents(+9K). 

So the above I think qualifies as a flash freeze, and all this despite claims of temps 2 - 4C above average?

I will agree that most of this is coastal ice, although I am not sure how much of it can be slush, and if it is, how long it will remain as slush.  This newly formed 'slush ice' is also now  moving outwards to the 'inner' islands around the  Siberian coast.  

I can see the freeze continuing for several days yet in these areas,  as there is a lot of 'easy' water to continue freezing.

I guess we will soon find out if the SST's are as high as claimed.

Meantime the main arctic ice pack continues its now steady increase in size and depth, particularly towards the Jan Mayen and Severena Novaya Islands. Today the pack made it to the Jan Mayen Islands and joined the local ice freeze starting up there over the last 2 days. The CAB (Central) ice pack gained a further (+35K) today as a result

To give the extreme amount of ice gain, it has also required some help  from North America - and this also answered the call in spades, with the very cold temps being seen in the area right now.

Greenland(+29K) and Baffin(+19K) were expected, but Hudson gained (+18K) and the CAA gained a whopping (+55K), as cold air flooded south.

So, today is just a first attempt at the rapid refreeze, there is still a long way to go.   It appears to me that it confirms my prediction of what  would happen starting this weekend (a week ago on here).

Weather conditions (predictions from CR  (GFS)) are becoming benign over much of the Arctic, with a more gentle east or south east wind over the Siberian Arctic.... this I feel will only help the refreeze as the sun has either set or is now very low in the sky, allowing the temperatures to fall over the Siberian snowfields and the newly formed ice.   

 I could still be proved wrong. I watched the same things happen last year(and reported on it), and I feel that the conditions are very similar, hence my relative short term optimism for rapid sea ice growth over the next month.

MIA

 

    

 

Edited by Midlands Ice Age
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3 hours ago, Steve Murr said:

So just to add heres the date the siberian ice was all covered last year courtesy of the post below

November 4th.BE218743-5D9E-4247-AA1E-FE513CF46D91.thumb.jpeg.8b34b96cd19a75529a1d000c4bfa660d.jpeg

 

Based on that I will go with the 15th-18th of November this year 2 weeks later.

2019 was the latest on record for the Siberian ice..

OK...

Let's see what happens.

Perhaps the 4th Nov may be a better date to judge.

Last year took an extra week (4 to 7days)  to freeze up a small area in Kara, it was more a less complete by 1st Nov. 

My point is that the Siberian ice will freeze up this year, and I think it is about 7 days (possibly a bit more) later in extent terms,

Ice extent (in the peripheral areas) will be affected by weather conditions over the short and medium term. 

BUT the ice in the main pack seems to have thickened much more this year (according to DMI) - see above charts;  which you have not mentioned. Thick ice in Chukchi is one of the main drivers of ice retention in the Arctic, as the ice normally rotates around the Beaufort gyre (Ie clockwise), as it takes longer to get expelled. 

This has to be a good thing for the  long term, as this ice will be less prone to freeze out next year and possibly go on to produce multi year ice?

MIA     

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9 hours ago, Steve Murr said:

So just to add heres the date the siberian ice was all covered last year courtesy of the post below

November 4th.BE218743-5D9E-4247-AA1E-FE513CF46D91.thumb.jpeg.8b34b96cd19a75529a1d000c4bfa660d.jpeg

 

Based on that I will go with the 15th-18th of November this year 2 weeks later.

2019 was the latest on record for the Siberian ice..

We also got to remember the 19/20 winter season was dominated by a positive AO which discourages much ice compactness in the Siberian sea regions. A negative AO tends to thicken the ice in Siberia with high pressure usually orientating in a way which benefits oce thickening. The 17/18refreeze was an example as 2018 started the melt season with quite thick Siberian ice, total opposite of this year. 

So even though refreeze looks like it will take longer, it does not fully mean the ice will end up thinner than last year. I would not be surprised if we see the Laptev sea still got open water even upto the 3rd week of November. 

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I made a little thread on huge importance of albedo of sea ice in Arctic, and how present more favourable weather patterns in Siberian landmass and seas at least measured aloft, are not reflecting on surface due to elevated SSTs, much worse than I anticipated. I’ve only really got really invested into this ice stuff this year, I have been checking it here and there, but now it’s an area I’m very interested in, very fascinating, here’s hoping we get some good news eventually. 😳

 

Edited by Daniel*
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Re the above posts...

>>>>>>Siberian ice ignores apparent high SST's!    <<<<<<

Masie today a total of 6083K Km2, a smaller increase of just 223K Km2, Still in last position, but closing rapidly again on 2019. 

Today was made more astounding in that 90% of the refreeze occurred in exactly the area (Siberian Arctic) that it is supposed to be too warm to freeze.  

200K Km2 was gained in the Eastern Arctic sea areas.

Area totals -

Beaufort (+27K Km2)  - freezing back into the coast again.

Chukchi - continues to grow (+47K) 

ESS - now expanding along the coastline eastwards towards the Bering Strait,as well as joining in with the Laptev refreeze..

Laptev - general overall increase thickening out towards the inner islands. (+29K), though some areas managed to  reduce slightly

Kara -  again the star (+49K). Ice formed along the coast and also more significantly, possibly,  south of Severna Novaya. The main pack appears to have reached this island now,

Barents (+6K), with ice starting to form south of Jan Mayen and a bit around Svalbard.

I make that about 200K Km2.  In fact about the same as yesterday's increase.

Elsewhere (Western hemisphere) gains in Greenland(+0K), Baffin(+2K), CAA(+10K), Hudson(+1K) and Central(CAB) with +10K. 

CAB is more interesting as the western edge of the expanding pack appeared to recede a bit, but it was full steam ahead around the outer islands for an overall gain..  

So 2 days large gains in the area under discussion.  

Let us all hope it continues>>>

MIA

Edited by Midlands Ice Age
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According to the NSIDC extent, despite an increase of 145k on the 25th, the gap between 2020 and the next lowest year (2019) has grown.

So 2020 is now lowest on record by 679k, or more than the land area of Norway and Finland combined.

NSIDC25th.thumb.jpg.8fd4166e2d8c34c7a787387056f0e471.jpg

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17 hours ago, Daniel* said:

I made a little thread on huge importance of albedo of sea ice in Arctic, and how present more favourable weather patterns in Siberian landmass and seas at least measured aloft, are not reflecting on surface due to elevated SSTs, much worse than I anticipated. I’ve only really got really invested into this ice stuff this year, I have been checking it here and there, but now it’s an area I’m very interested in, very fascinating, here’s hoping we get some good news eventually. 😳

 

Super interesting @Daniel* - thanks for sharing!

I'm not sure albedo tells the whole story, though...think the discrepancy you highlight is mainly due to heat being emitted from the relatively warm open water north of Siberia, which is stopping air temperatures falling really low.

There is almost no sunlight that far north by this time of year, so albedo is less important than in, say, spring-time, when there is a lot of incoming solar radiation to reflect.

Two important factors are the relative specific heat capacities of land and water, which allows land-masses to cool down far faster than oceans at this time of year, and the effectiveness of snow as an emitter of longwave radiation. These two effects combine over the snow-covered parts of Russia and North America.

The Arctic sea ice, for its part, acts like a lid on the warm sea water below it, preventing the release of heat from the Arctic Ocean into the atmosphere. Much of the sea-ice will also have snow cover, too, which will allow it to radiate heat effectively into the polar night when conditions are still and cloudless, helping lower temperatures further.

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3 hours ago, Stravaiger said:

Super interesting @Daniel* - thanks for sharing!

I'm not sure albedo tells the whole story, though...think the discrepancy you highlight is mainly due to heat being emitted from the relatively warm open water north of Siberia, which is stopping air temperatures falling really low.

There is almost no sunlight that far north by this time of year, so albedo is less important than in, say, spring-time, when there is a lot of incoming solar radiation to reflect.

Two important factors are the relative specific heat capacities of land and water, which allows land-masses to cool down far faster than oceans at this time of year, and the effectiveness of snow as an emitter of longwave radiation. These two effects combine over the snow-covered parts of Russia and North America.

The Arctic sea ice, for its part, acts like a lid on the warm sea water below it, preventing the release of heat from the Arctic Ocean into the atmosphere. Much of the sea-ice will also have snow cover, too, which will allow it to radiate heat effectively into the polar night when conditions are still and cloudless, helping lower temperatures further.

Quite correct Stav..

Look at the current DMI Arctic (above 80 degree) temperature chart.

image.thumb.png.508abd0b497464f430292d96c767b1a8.png

 As the ice increases, so the temperature is starting to drop quickly now. This is caused by the water vapour in the low level (mainly fog/mist/H2O? caused by the warmer seas evaporation,  being frozen out at the surface hence allowing more and more heat to be lost by radiation (less water vapour/cloud, etc). This in turn leads to the more rapid drop in temperatures at the surface. 

It clearly happens and can be seen by the more rapid drop in temps in the above map.  

In addition, look at the DMI ice map for today and last year (same date).

           2019/10/25                                                           2020/10/25

image.thumb.png.a305576bdfad68c46cdc504f83f23fcc.pngimage.thumb.png.c64d322d8e25c73909fdc00fc570c709.png     

Despite the obviously less ice extent in the Siberian seas this year,  (however more in Beaufort and the CAA!), the increase in depth of ice  in the Central Arctic ice is sheet is still meaning that there is a greater amount of ice (volume) in the  Arctic than last year.  (see the insert)

This ice in the CAB is continuing to thicken rapidly - (last 10 days)

           14/10/2020                                                                  25/10/2020

  image.thumb.png.65b890c06049446718afabc83d207d52.png             image.thumb.png.7d53e4a98c185dba9c77dc21abc913ee.png  

 

The ice  in the shallower waters of the Siberian seas can be made up in a week. (depending upon the weather) ?

The ice in Central Arctic means that probably we will be more likely to not see the larger areas of blue in the first graph above for 2019, during the 2021 ice refreeze (obviously lots of caveats). 

Last year it took until Jan (2020), to get anywhere near the thickness we have in the central ice pack today.

                 5/1/2020

image.thumb.png.907bd998ba751cac2ebedb761e3cc5da.png

 

My own feelings (looking back) are that I would rather be in this years position than we were at the same stage in 2019.

I think this is the key reason why I do not join in the pessimism displayed by several of the posters. 

MIA

 

Edited by Midlands Ice Age
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