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Author Topic: The 2019/2020 freezing season  (Read 263777 times)

johnm33

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Re: The 2019/2020 freezing season
« Reply #900 on: February 14, 2020, 11:21:27 AM »

Looking at Nullschool  suggests that a combination of high pressure and low tides were contributing to a rush for the exits.

uniquorn

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Re: The 2019/2020 freezing season
« Reply #901 on: February 14, 2020, 12:55:05 PM »
Despite the drift, plenty of 1-2yr old ice is still melting on arrival at Svalbard. The forecast deep cyclone over Barents/Kara persists from the long term into medium term.
Extent on feb10 "10,048 k, 790 k (8.5%) MORE than the average last 10 years gain to date of 9,258 k."
Near term Kara drift possibly outweighs upcoming Barents drift and melt.
Bering sea already way over recent maximums
Baffin at all time low, very little MYI component.
Relatively mild over Okhotsk coastal region.

Early maximum extent?
Wipneus regional area feb12
Worldview, Atlantic side, https://go.nasa.gov/3bFFajp (rotated-north is down)

Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #902 on: February 14, 2020, 02:04:15 PM »
"The most revolutionary thing one can do always is to proclaim loudly what is happening" - Rosa Luxemburg

gandul

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Re: The 2019/2020 freezing season
« Reply #903 on: February 14, 2020, 03:06:47 PM »
Early maximum extent?

Who'd have thunk it? "Snow White"!

http://GreatWhiteCon.info/2020/01/wheres-the-thickest-arctic-sea-ice-gone/#comment-315058

"Fluctuations are normal this time of year."
The perfect non-explanation of it

Unmex Chingon

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Re: The 2019/2020 freezing season
« Reply #904 on: February 14, 2020, 03:41:09 PM »
Early maximum extent?

Who'd have thunk it? "Snow White"!

http://GreatWhiteCon.info/2020/01/wheres-the-thickest-arctic-sea-ice-gone/#comment-315058

Jim - Are you calling it the maximum extent already? Yes or No - Or are you "kind of" in case it does happen and you can say you told us so?

pauldry600

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Re: The 2019/2020 freezing season
« Reply #905 on: February 14, 2020, 05:26:40 PM »
I'll call it

No it will go up and down until the end of month at least

There

Watch it drop like a stone now

Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #906 on: February 14, 2020, 05:53:10 PM »
Jim - Are you calling it the maximum extent already? Yes or No - Or are you "kind of" in case it does happen and you can say you told us so?

I'm teasing a subset of Judith Curry's denizens.
"The most revolutionary thing one can do always is to proclaim loudly what is happening" - Rosa Luxemburg

gerontocrat

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Re: The 2019/2020 freezing season
« Reply #907 on: February 14, 2020, 06:43:37 PM »
From one of my posts on the extent thread
___________________________
Freezing Outlook?

GFS says overall Arctic temperature anomalies increasing from +1.7 to +2.9 celsius over the next 5 days.

The Bering /Chukchi/Okhotsk, and Canadian far North mostly very cold to extremely cold.
The Atlantic Front remains and will remain a battleground between warm southerlies heading up from the Atlantic and cold Northerlies out of the CAB & Russia, and the southerlies perhaps reaching the Barents Sea on occasion.

At the same time significant +ve anomalies occasionally entering the Kara/Laptev into the CAB from interior Western Russia.

A messy picture, being the gathering strength of the annual battle of warmth from the rising sun fighting the bitter cold of the Arctic Ocean (as we are now 50+ days after the winter solstice). To add to that, the extra strong polar vortex in the Atlantic spawned Storm Ciara and now Storm Dennis which look like it has caused, is causing and will cause havoc in the Atlantic Front.

This is the time of year when area and extent go up and down so much as to make projections a mugs' game.
__________________________
When looking beyond 5 days the crystal ball goes foggy.
It is about 4 weeks before the average date of maximum, and the minimum date of maximum since 2002 is 15th Feb (2015), 2nd earliest 28 Feb (2016).

As I am in need of light relief I look forward to science-based forecasts of the maximum date and maximum value
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Shared Humanity

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Re: The 2019/2020 freezing season
« Reply #908 on: February 14, 2020, 11:02:00 PM »
great webinar!

jdallen

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Re: The 2019/2020 freezing season
« Reply #909 on: February 15, 2020, 07:19:54 AM »
From one of my posts on the extent thread
<snippage>
A messy picture, being the gathering strength of the annual battle of warmth from the rising sun fighting the bitter cold of the Arctic Ocean (as we are now 50+ days after the winter solstice). To add to that, the extra strong polar vortex in the Atlantic spawned Storm Ciara and now Storm Dennis which look like it has caused, is causing and will cause havoc in the Atlantic Front.

This is the time of year when area and extent go up and down so much as to make projections a mugs' game.
__________________________
When looking beyond 5 days the crystal ball goes foggy.
It is about 4 weeks before the average date of maximum, and the minimum date of maximum since 2002 is 15th Feb (2015), 2nd earliest 28 Feb (2016).
Incisive as ever.

I think we may look back at the explosion of Storm Ciara/Dennis as being a key point in the year.  As you well point out, prediction right now is a mugs game, but the train of heat starting in the Caribbean stretching all the way to Scandinavia is astounding, along with the incredible low pressures they achieved.

All that energy has been crashing into the Barents/Kara region, and the low pressure systems themselves are predicted to track north through the Norwegian Sea into the Barents over the next few days.  At the least, that will make expansion of ice very difficult, and may dredge heat from depth that will similarly impede freezing.  I will be watching how the systems evolve closely, as well as the incredible atmospheric rivers exporting of moisture out of Caribbean and elsewhere
 in the tropical Atlantic.
This space for Rent.

johnm33

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Re: The 2019/2020 freezing season
« Reply #910 on: February 15, 2020, 01:21:09 PM »
I'll take a punt, stall/small drop for a couple of days, then steeper drop for another couple, likely into new territory [on G's graph]  then accelerated drop which will either go into overdrive or halt and reverse dependent on whether the low moves over the deep [St. Anna/Nansen] or heads south over Siberia.

Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #911 on: February 15, 2020, 01:29:38 PM »
I think we may look back at the explosion of Storm Ciara/Dennis as being a key point in the year.

As my alter ego has just pointed out over on Twitter:

In due course the "phenomenal winter warmth" from Storm Dennis will reach the  North Pole:
"The most revolutionary thing one can do always is to proclaim loudly what is happening" - Rosa Luxemburg

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Re: The 2019/2020 freezing season
« Reply #912 on: February 15, 2020, 06:22:52 PM »
I think we may look back at the explosion of Storm Ciara/Dennis as being a key point in the year.

As my alter ego has just pointed out over on Twitter:

In due course the "phenomenal winter warmth" from Storm Dennis will reach the  North Pole:

The flow goes via Scandinavia and up towards the North Pole via the Kara sea so any tropical elements of the low pressure system is well gone but yes temperatures across the Kara sea and up towards the pole is set to rise quite a bit. May not last long though so I doubt it will have too much affects apart from potential ice loss in the Kara sea.

Shared Humanity

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Re: The 2019/2020 freezing season
« Reply #913 on: February 15, 2020, 07:17:03 PM »
I think we may look back at the explosion of Storm Ciara/Dennis as being a key point in the year.

As my alter ego has just pointed out over on Twitter:

In due course the "phenomenal winter warmth" from Storm Dennis will reach the  North Pole:

Warmth has been intruding into the Arctic from western Russia for much of the winter. My guess is the Chukchi, Laptev and Kara Seas are going to have a bad melt season.

Paul

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Re: The 2019/2020 freezing season
« Reply #914 on: February 15, 2020, 09:11:53 PM »
I think we may look back at the explosion of Storm Ciara/Dennis as being a key point in the year.

As my alter ego has just pointed out over on Twitter:

In due course the "phenomenal winter warmth" from Storm Dennis will reach the  North Pole:

Warmth has been intruding into the Arctic from western Russia for much of the winter. My guess is the Chukchi, Laptev and Kara Seas are going to have a bad melt season.

That's not what I been seeing, for the most part the Barants sea lows has been deflected by the PV and colder winds have dominated the Kara sea as a result, its only in the last few days warmer winds have been hitting the Kara sea area and ice is now lifting and retreating(although probably not melting) this is look to continue for a while yet.

Chukchi Sea ice looks more resilient than the last 2 years due to lack of ridges heading into the Bering sea, of course things can change but at the moment I'll be surprised if we l see an early retreat of the Chukchi sea ice like we have seen in the past 2 years.

Aluminium

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Re: The 2019/2020 freezing season
« Reply #915 on: February 16, 2020, 09:03:39 AM »
February 1 - 15.

2019.

blumenkraft

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Re: The 2019/2020 freezing season
« Reply #916 on: February 16, 2020, 12:22:22 PM »
North Atlantic Storminess – February 13-15, 2020

Quote
A rapidly intensifying low pressure system made its way into the Atlantic on Tuesday, 11 February 2020 and quickly grew into a powerful extratropical cyclone producing hurricane force winds by Thursday, 13 February 2020. By 0600 UTC on 14 February 2020, the low bottomed out with a minimum low pressure of 929mb. This system deepened by more than 40 mb in 24 hours during its rapid intensification phase, classifying it as a “bomb” cyclone. It tracked north towards Iceland where it caused hurricane force wind gusts, the highest gust, although terrain enhanced, reached 159 mph (https://www.severe-weather.eu/recent-events/near-record-wind-gusts-255kmh-hafnarfjall-iceland-mk/). These gusts were recorded on the leading edge of the cyclone where the cold conveyor belt north of the occluded front in the N-NE quadrants played a role.

Link >> https://satelliteliaisonblog.com/2020/02/16/north-atlantic-storminess-february-13-15-2020/

Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #917 on: February 16, 2020, 02:26:57 PM »
North Atlantic Storminess – February 13-15, 2020

See also the February 16th "Storm Dennis" update:

https://forum.arctic-sea-ice.net/index.php/topic,2984.msg249638.html#msg249638
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Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #918 on: February 16, 2020, 02:29:35 PM »
Here's the latest update of "Snow White's" novel "near real time" Arctic sea ice volume metric:

http://GreatWhiteCon.info/2020/01/wheres-the-thickest-arctic-sea-ice-gone/#Feb-16

Please note that there is a known problem with the NRT data from January 31st onwards.
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Unmex Chingon

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Re: The 2019/2020 freezing season
« Reply #919 on: February 16, 2020, 05:06:28 PM »
Jim - Are you calling it the maximum extent already? Yes or No - Or are you "kind of" in case it does happen and you can say you told us so?

I'm teasing a subset of Judith Curry's denizens.

Got it...  You did NOT call it yet then...

blumenkraft

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Re: The 2019/2020 freezing season
« Reply #920 on: February 16, 2020, 06:15:17 PM »
7-day hindsight mean temperature anomalies.

Sunday to Sunday.

blumenkraft

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Re: The 2019/2020 freezing season
« Reply #921 on: February 16, 2020, 06:28:30 PM »
Sunday to Sunday Fram export via SAR.

Shared Humanity

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Re: The 2019/2020 freezing season
« Reply #922 on: February 16, 2020, 07:08:55 PM »
Here's the latest update of "Snow White's" novel "near real time" Arctic sea ice volume metric:

http://GreatWhiteCon.info/2020/01/wheres-the-thickest-arctic-sea-ice-gone/#Feb-16

Please note that there is a known problem with the NRT data from January 31st onwards.

Wow! Just wow! Given that volume is the most important metric when measuring the long term health of arctic ice, this chart is scary.

Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #923 on: February 16, 2020, 07:48:41 PM »
Wow! Just wow! Given that volume is the most important metric when measuring the long term health of arctic ice, this chart is scary.

Agreed, but it will be interesting to compare those numbers with the mid-month PIOMAS update, assuming that one appears this month.

For some reason this year CS2 and PIOMAS seem to be at variance more than usual, so a pinch or two of salt is required.
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Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #924 on: February 17, 2020, 09:47:04 AM »
JAXA's AMSR2 extent has turned down again, but Wipneus's high resolution 3.125 km grid area never turned up! Hi res extent did, but barely.

JAXA includes the 16th. Hi res does not.
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Iain

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Re: The 2019/2020 freezing season
« Reply #925 on: February 20, 2020, 11:55:50 AM »
Daylight has returned to the Parry channel, a potential export route late in the melting season

There is movement of ice East of the ice bridge:
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Iain

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Re: The 2019/2020 freezing season
« Reply #926 on: February 20, 2020, 11:58:23 AM »
2020 extent of moving ice is further West than in 2019, but not so far as 2018 or 2017
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uniquorn

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Re: The 2019/2020 freezing season
« Reply #927 on: February 20, 2020, 12:19:52 PM »
https://go.nasa.gov/37EBZFr, Okhotsk sea (north), feb10-20, unihamburg-amsr2uhh inset. ctr

edit: Early maximum extent just about hanging in there. Probably dependent mostly on possible increases in Okhotsk and Baffin/Newfoundland (still at all time low). Bering still high for recent years and Barents/Kara forecast for southerly winds, so drifting north. Very little MYI in Greenland and Baffin Seas.
Wipneus regional extent, feb18. updated to feb19 - barentsz/kara drop, baffin/nfld rise, okhotsk slightly up, bering(very southerly) likely over reached with the continuous drift.
hmm St Lawrence
« Last Edit: February 20, 2020, 10:58:16 PM by uniquorn »

gerontocrat

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Re: The 2019/2020 freezing season
« Reply #928 on: February 20, 2020, 02:35:58 PM »
Looks like bloody cold in Canada (and much of USA) over the next few weeks.

Also looks likely to be a big contrast with Northern Europe and Siberia for some time to come.

https://weather.gc.ca/saisons/image_e.html?img=mfe1t_s
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uniquorn

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Re: The 2019/2020 freezing season
« Reply #929 on: February 20, 2020, 05:59:58 PM »
Drift on the Atlantic side before the forecast warm spell.
uni-hamburg amsr2-uhh, atl, feb10-19

The Walrus

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Re: The 2019/2020 freezing season
« Reply #930 on: February 21, 2020, 12:40:25 AM »
That cold/warm dichotomy may stall any growth in ice extent.  Most of the growth potential is on the European side.

uniquorn

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Re: The 2019/2020 freezing season
« Reply #931 on: February 21, 2020, 10:03:48 AM »
New maximum extent.
[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.
February 20th, 2020:
     14,099,241 km2, a century increase of 114,662 km2:o
     Source: https://ads.nipr.ac.jp/vishop/#/extent
Less running commentary ;)

Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #932 on: February 21, 2020, 10:26:58 AM »
New maximum extent.

It will be interesting to discover when Wipneus's hi res numbers follow suit. In the mean time DMI T2 has reacted as predicted:
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Jontenoy

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Re: The 2019/2020 freezing season
« Reply #933 on: February 21, 2020, 05:35:11 PM »
Why does sea ice volume reach  a maximum 6 weeks after sea ice extent ?

Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #934 on: February 21, 2020, 05:50:29 PM »
Why does sea ice volume reach  a maximum 6 weeks after sea ice extent ?

Because the thin peripheral ice starts to melt even whilst the thick central ice continues to get thicker.
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Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #935 on: February 22, 2020, 02:31:46 PM »
It's a bit cloudy, and today's daylight images haven't arrived yet, but band 31 reveals some recent movement in the Beaufort Sea:

https://go.nasa.gov/2ujNZ1x
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Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #936 on: February 22, 2020, 02:36:53 PM »
It's not summer yet, but this new discussion paper makes interesting reading nonetheless:

https://www.the-cryosphere-discuss.net/tc-2020-35/

Quote
We report on results of a systematic inter-comparison of 10 global sea-ice concentration (SIC) data products at 12.5 to 50.0 km grid resolution from satellite passive microwave (PMW) observations for the Arctic during summer. The products are compared against SIC and net ice-surface fraction (ISF) – SIC minus the per-grid cell melt-pond fraction (MPF) on sea ice – as derived from MODerate resolution Imaging Spectroradiometer (MODIS) satellite observations and observed from ice-going vessels.
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uniquorn

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Re: The 2019/2020 freezing season
« Reply #937 on: February 22, 2020, 11:25:39 PM »
Recent movement north of Greenland. rammb feb18-22
North is left, Greenland top right.
https://col.st/JoIXp

edit: Today's worldview image https://go.nasa.gov/2unex1X
click for full resolution
« Last Edit: February 23, 2020, 11:52:24 AM by uniquorn »

blumenkraft

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Re: The 2019/2020 freezing season
« Reply #938 on: February 23, 2020, 10:46:28 PM »
Hindsight time!

First, the ice drift map.

blumenkraft

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Re: The 2019/2020 freezing season
« Reply #939 on: February 23, 2020, 10:47:24 PM »
7-day mean temperature anomalies.

blumenkraft

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Re: The 2019/2020 freezing season
« Reply #940 on: February 23, 2020, 10:48:12 PM »
And the thick ice down the drain, the Fram export via SAR.

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Re: The 2019/2020 freezing season
« Reply #941 on: February 24, 2020, 11:51:37 AM »
Winds in the strait will be strong next days.

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Re: The 2019/2020 freezing season
« Reply #942 on: February 25, 2020, 05:09:42 AM »
There is very definitely a serious back-and-forth dance going on, especially on the Atlantic side - day over day swings of 50,000km2 both up and down.

The divergence in increase and rate between area and extent - in some cases it appears with area dropping while extent increases - has me thinking most recent increases are the formation of lead ice in between older floes.  Add to this, that a significant fraction of the increase in both is in Okhotsk, that suggests the other changes are less meaningful.

I think we are very close to max, and the continuing high temperatures aren't particularly good for late season thickening that needs to take place; DMI 80n temps continue to run close to 10c above normal.

Northern hemisphere snow distribution is uneven - modest positive anomalies across parts of Siberia and N. America, but significant regions at high latitude in Europe that are currently snow-free with daily increasing heat.

Again, not sure what to conclude yet, but nothing happening this year I can consider any sort of a "recovery" even with the strong polar vortex we had for a while.  That still hasn't prevented big lows from pumping heat out of the tropics to high latitude.
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F.Tnioli

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Re: The 2019/2020 freezing season
« Reply #943 on: February 26, 2020, 12:14:38 PM »
...
Northern hemisphere snow distribution is uneven - modest positive anomalies across parts of Siberia and N. America, but significant regions at high latitude in Europe that are currently snow-free with daily increasing heat.
...
My bold. I said it a while ago about "no snow cover during late winter triggers massive albedo feedback", meaning by this significant insolation in February, March and April hitting dark Earth surface instead of white snow. Which brings in - as it stands right now - truly massive extra heat into the system where and when this heat is not supposed to be. Above posted temperature anomalies for large area south of Scandinavia and large parts of Siberia - are mind-boggling to me.

I foresee highly unusual melting season as a result. In particular, i expect great number of strong cyclones entering the Arctic and some, possibly, forming in it much earlier and stronger than ever before. Russian Far East and much of Canada remaining cold while Atlantic side warming up at an accelerating pace (low albedo plus rapidly increasing effective insolation as Sun gets higher over horizon for longer times in more and more places) - will create huge air masses of wildly different temperature, which will sooner or later interact with quite predictable result. Not good for ice, i guess...
To everyone: before posting in a melting season topic, please be sure to know contents of this moderator's post: https://forum.arctic-sea-ice.net/index.php/topic,3017.msg261893.html#msg261893 . Thanks!

Hefaistos

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Re: The 2019/2020 freezing season
« Reply #944 on: February 26, 2020, 12:46:45 PM »

My bold. I said it a while ago about "no snow cover during late winter triggers massive albedo feedback", meaning by this significant insolation in February, March and April hitting dark Earth surface instead of white snow. Which brings in - as it stands right now - truly massive extra heat into the system ...

hi.
I live on 60N in Scandinavia and this has been the 'new normal'  winter for a decade at least. Our winters are getting much shorter as a result.

But there is no punch at all in the sun at these latitudes in Feb., and March. It's not gonna bring in "massive extra heat" as you write. In April insolation is strong, but by then snow is mostly gone anyway.

philopek

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Re: The 2019/2020 freezing season
« Reply #945 on: February 26, 2020, 03:25:18 PM »
hi.
I live on 60N in Scandinavia and this has been the 'new normal'  winter for a decade at least. Our winters are getting much shorter as a result.

But there is no punch at all in the sun at these latitudes in Feb., and March. It's not gonna bring in "massive extra heat" as you write. In April insolation is strong, but by then snow is mostly gone anyway.

A few remarks:

- you may not feel the punch in cold air-masses and the frequent inversions where the air at ground level and close to it is colder than at some higher altitudes.

- nevertheless the energy that can be measured, even at low sun-angles IS SIGNIFICANT.
. In fact, compared to zero it's even huge while not TOP-Level of course.

- Said energy, meeting darker surfaces, makes a "HUGE" difference. Not only in absorbing
. energy but also by quicker melting of the remaining and/or existing snow cover.

- 60N is slightly north of  Oslo and goes through St. Petersburg to name just 2 of the largeer and
. better known places. That's "NOT" very far north, it's around the northernmost tip of the UK.

Whatever the details, the impact on darker surfaces, compared to white surfaces, is significant at "ANY" sun angle. Even though our thickly dressed protected skin does not feel that way, last but no least due to wind and humidity as 2 of several key factors. More humid air in winter often sticks to the ground with an impact as described above.

There is more to it but then I only wanted to +1 F.T.,
I found his description, in all briefness, kind of spot on.

Thing is that if we write long/much, it's frowned upon. If we write short, those with a tendency to find a hair in every soup would easily find their "angle of attack" while the original meaning
was quite accurate and mostly well meant.

« Last Edit: February 26, 2020, 04:56:48 PM by philopek »

jdallen

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Re: The 2019/2020 freezing season
« Reply #946 on: February 26, 2020, 09:36:56 PM »
hi.
I live on 60N in Scandinavia and this has been the 'new normal'  winter for a decade at least. Our winters are getting much shorter as a result.
<snip>

A few remarks:

- you may not feel the punch in cold air-masses and the frequent inversions where the air at ground level and close to it is colder than at some higher altitudes.

- nevertheless the energy that can be measured, even at low sun-angles IS SIGNIFICANT.
. In fact, compared to zero it's even huge while not TOP-Level of course.

- Said energy, meeting darker surfaces, makes a "HUGE" difference. Not only in absorbing
. energy but also by quicker melting of the remaining and/or existing snow cover.
<snip>

+1 to your +1;

I think to put it in context Hefaistos, you need to think not necessarily about what's happening now, but where conditions will be in 3-4 weeks.

What is happening is setup, much like how much running room you have leading up to a broad jump.  By losing snow this early, and picking up what are modest but still significant amounts of solar energy means that considerably more energy will
(1) ... be captured directly at Arctic latitudes
(2) ... be available early in the melt season
(3) ... not be required for/buffered by local phase change (e.g. melting snow locally)
(4) ... indirectly permit more transport of heat to the Arctic from lower latitudes. (primarily via
          increased moisture)

We are not necessarily increasing the amount of energy available, but we are extending the melt season by way of making it possible to capture that energy earlier.

Another way of looking at it is to think about melt rate at the peak of the season.  The difference between 2012 and pretty much every year starting with 2016 is 7-10 days of peak melt.  That's the razor's edge we are on.

The earlier the heat can be made available is that much more opportunity for us to have those peak melt days, and regardless (within reason) of the starting ice conditions that makes a 2012 event more likely.

If we have another "perfect" melt season like 2012, it means blowing past that year into the realm of sub-3 million km2 extent.  *Well* past.

We've been rolling dice with this for the best part of a decade.  Each additional year has loaded the dice progressively in favor of melt.

That's why lots of bare ground at high latitudes is concerning, even before the equinox.
This space for Rent.

Hefaistos

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Re: The 2019/2020 freezing season
« Reply #947 on: February 26, 2020, 10:43:15 PM »
Thanks for your input.
F.Tnioli made a pretty bold statement:
Quote
I foresee highly unusual melting season as a result. In particular, i expect great number of strong cyclones entering the Arctic and some, possibly, forming in it much earlier and stronger than ever before.

I don't see the link between a very gradual loss of albedo over land in the early months of the year when insolation is very weak, to the formation of a "great number of strong cyclones".

The Arctic sea ice has had a good year so far compared to the decadal average.
I hypothesize we will have an average melting season without much drama.

The Walrus

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Re: The 2019/2020 freezing season
« Reply #948 on: February 26, 2020, 10:49:01 PM »
Thanks for your input.
F.Tnioli made a pretty bold statement:
Quote
I foresee highly unusual melting season as a result. In particular, i expect great number of strong cyclones entering the Arctic and some, possibly, forming in it much earlier and stronger than ever before.

I don't see the link between a very gradual loss of albedo over land in the early months of the year when insolation is very weak, to the formation of a "great number of strong cyclones".

The Arctic sea ice has had a good year so far compared to the decadal average.
I hypothesize we will have an average melting season without much drama.

Let me be the first to agree with you.  Let’s see how many follow suit.

kassy

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Re: The 2019/2020 freezing season
« Reply #949 on: February 26, 2020, 10:55:30 PM »
Another way of looking at it is to think about melt rate at the peak of the season.  The difference between 2012 and pretty much every year starting with 2016 is 7-10 days of peak melt.  That's the razor's edge we are on.

Interesting point. This year might be a good test with all the extras we get via the pandemic. There was already going to be a change in shipping emissions and that signal got extra strong with reduced shipping and there are lots of other knock on effects on the way.

Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.