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be cause

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Re: The 2019/2020 freezing season
« Reply #200 on: October 08, 2019, 02:24:01 AM »
 I am certain that anything like the GAC would have halved the final numbers this year . Mosaic news reply 87 .. A-team SMOS runs show how little ice was left over 50cm thick . With a little bit of stirring almost any time in the late summer and the 50cm SMOS line could easily have been the minimum extent/area line .
 It was very much 'can sunny anti-cyclonic weather all summer melt all the ice' ?  Not yet . But scarily close . We are not so much 4,000,000 sq kms away from ice free . We are 50 cms away ! .. b.c.
 

 


?
2007 + 5 = 2012 + 4 = 2016 + 3 = 2019 ...

Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #201 on: October 08, 2019, 10:52:47 AM »
The IPCC's recently released "Special Report on the Ocean and Cryosphere in a Changing Climate":

https://www.ipcc.ch/srocc/home/

Here's a recording of the associated press conference:



The first 37 mins are rather boring!
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Iain

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Re: The 2019/2020 freezing season
« Reply #202 on: October 08, 2019, 03:46:39 PM »
...Like I said, it's a tease this year, 2019 extent graph almost intersecting 2007....
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Aluminium

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Re: The 2019/2020 freezing season
« Reply #203 on: October 09, 2019, 06:59:51 AM »
October 4-8.

2018.

Wildcatter

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Re: The 2019/2020 freezing season
« Reply #204 on: October 09, 2019, 07:44:30 AM »
Someone keep an eye on the Beaufort Low this season!  + breakdowns of the Beaufort High. (sea level pressure).

It will be valuable insight for the freeze season, given some of correlation in the 2017 freeze season.

Anti-cyclonic circulation has been the general trend for about 15-20 years? And the connection with the gyre ice movement (clockwise).

https://www.sciencedaily.com/releases/2018/03/180320123450.htm

https://www.researchgate.net/publication/323879547_Collapse_of_the_2017_Winter_Beaufort_High_A_Response_to_Thinning_Sea_Ice

Aleph_Null

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Re: The 2019/2020 freezing season
« Reply #205 on: October 09, 2019, 12:19:07 PM »
Full-size version available in the Nullschool Animations thread:
https://forum.arctic-sea-ice.net/index.php/topic,2905.msg232452.html#msg232452

pressure, wind & density over sea ice concentration
Hindcast: 10/4 to 10/9, Forecast: 10/9 to 10/12.

AMSR2 (U. Bremen sea ice concentration) + MSLP (mean sea level pressure) + IWPD@850hPa (instantaneous wind power density: air density ρ, wind velocity v: ½ρv3) [tiny version]

gerontocrat

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Re: The 2019/2020 freezing season
« Reply #206 on: October 09, 2019, 01:34:10 PM »
Temp anomalies still mostly +ve,
SST anomalies still mostly +ve.

Re-freeze still resisted?
"Para a Causa do Povo a Luta Continua!"
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macid

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Re: The 2019/2020 freezing season
« Reply #207 on: October 09, 2019, 01:52:51 PM »
I'm surprised the extent numbers are low after yesterday's polar crossing waft ripped the ice apart, polar view 8 to 9 oct around 100°E / 84-87°N approximately overlapped (click to play)

uniquorn

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Re: The 2019/2020 freezing season
« Reply #208 on: October 09, 2019, 02:12:21 PM »
There's still a bit of melt and compaction on the atlantic side

Iain

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Re: The 2019/2020 freezing season
« Reply #209 on: October 09, 2019, 03:15:27 PM »
Charctic puts 2019 in second lowest extent for day of year - 4.879 against 4.882 for 2007.
"If I have seen further than others, it is by standing upon the shoulders of giants." Isaac Newton

Iain

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Re: The 2019/2020 freezing season
« Reply #210 on: October 09, 2019, 03:17:26 PM »
Oh, and I would like to make clear I have made many thousands of informative posts on this forum, it's just that my post count has been stuck at 62 since 1975.






 ;)
"If I have seen further than others, it is by standing upon the shoulders of giants." Isaac Newton

gerontocrat

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Re: The 2019/2020 freezing season
« Reply #211 on: October 09, 2019, 06:16:47 PM »
Oh, and I would like to make clear I have made many thousands of informative posts on this forum, it's just that my post count has been stuck at 62 since 1975.
 ;)
I wish my age had been stuck since 1975.
____________________
Meanwhile...

What happened to the "Icy Desert" (to quote A-Team) that was the Arctic Ocean?

& how much fog (apparently a great way of restricting heat loss from open water) is still around?

A paper suggests that Water Vapour Content may well be significant..

https://www.mdpi.com/2073-4433/8/12/241/htm
Enhanced MODIS Atmospheric Total Water Vapour Content Trends in Response to Arctic Amplification
Quote
Abstract: Arctic amplification (AA) is the phenomenon by which climate change is amplified in the Arctic with respect to global changes. It is partly related to the ice–albedo feedback mechanism. The Arctic region is experiencing a strong surface warming and a decrease in sea ice extent and thickness. This well-documented phenomenon appears to be accelerating in the last decades.

Several feedbacks are involved in the AA , notably those associated with the atmospheric hydrological cycle ....

Upward TCWV trends above the oceanic areas are discussed in lien with sea ice extent and sea surface temperature changes. Increased winter TCWV (up to 40%) south of the Svalbard archipelago are observed; these trends are probably driven by a local warming and sea ice extent decline. Similarly, the Barents/Kara regions underwent wet trends (up to 40%), also associated with winter/fall local sea ice loss. Positive late summer TCWV trends above the western Greenland and Beaufort seas (about 20%) result from enhanced upper ocean warming and thereby a local coastal decline in ice extent. ....Other TCWV anomalies are also presented and discussed in relation to the dramatic decline in sea ice extent and the exceptional rise in sea surface temperature.

Arctic amplification (AA)  is the phenomenon by which climate change is amplified in the Arctic with respect to global changes. It is partly related to the ice–albedo feedback mechanism. The Arctic region is experiencing a strong surface warming and a decrease in sea ice extent and thickness. This well-documented phenomenon .. appears to be accelerating in the last decades. Several feedbacks are involved in the AA , notably those associated with the atmospheric hydrological cycle . The warming of the lower part of the Arctic atmosphere  is found to be sensitive to the albedo changes due to increasing pollution agents (such as black carbon) on the Arctic sea ice/snow , loss of sea ice coverage, as well as the increase of the atmospheric northward transport of heat and moisture. The spatiotemporal distribution of water vapour and the amplitude of its response to Arctic climate change are major sources of uncertainty in the understanding and prediction of the amplification mechanism ]. Cloud and water vapour-related feedbacks to the AA are of enhanced interest
"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)

NotaDenier

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Re: The 2019/2020 freezing season
« Reply #212 on: October 10, 2019, 01:48:43 AM »
Temp anomalies still mostly +ve,
SST anomalies still mostly +ve.

Re-freeze still resisted?

Anyone notice you can see the shape of the ice pack in the temperature chart? Kind of cool.

Juan C. García

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Re: The 2019/2020 freezing season
« Reply #213 on: October 10, 2019, 06:01:51 AM »
October 4-8.
Could be that Lorenzo's waves took a toll on the Atlantic Ocean side, especially around Svalbard?
Strange to see such a drop on October.
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

peterlvmeng

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Re: The 2019/2020 freezing season
« Reply #214 on: October 10, 2019, 06:39:36 AM »
The slow down freezing is predictable. Does anyone remember that the torching heat and solar insolation surrounding the arctic basin from May to August? Now it is time for those heat totally release from the ocean until the accelerating freezing will come. Most people care about the arctic sea ice minimum. But I have to say more ice melt in the August means less heat in the arctic ocean. More ice left in the August and September means more heat restored in the ocean. Now it is time for those heat to dominate the situation. Interesting!!!

Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #215 on: October 10, 2019, 09:31:57 AM »
Could be that Lorenzo's waves took a toll on the Atlantic Ocean side, especially around Svalbard?
Strange to see such a drop on October.

If it was waves that did it I don't think they were from Lorenzo. There have been bigger storms in the far North Atlantic recently.
« Last Edit: October 10, 2019, 12:01:31 PM by Jim Hunt »
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

be cause

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Re: The 2019/2020 freezing season
« Reply #216 on: October 10, 2019, 09:54:34 AM »
indeed .. Lorenzo died over Ireland . But .. it had been expected to head Greenland way . It didn't , but it's warmth and moisture mostly did , joining and strengthening the storm that did provide the wind and warmth we have now seen the results of around Svalbard .
  the shape of the ice pack being seen in the 2m anomaly is becoming routine this time of year .. look back a year in the forecasts , it almost couldn't be otherwise  ... b.c.
 
2007 + 5 = 2012 + 4 = 2016 + 3 = 2019 ...

Pavel

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Re: The 2019/2020 freezing season
« Reply #217 on: October 10, 2019, 10:45:20 AM »
The remaining weeks of October are very important. Normally it should be a century uptick each day. 2019 can delay the fast refreeze because the peripheral seas have the extra heat stored. I'm curious to see how it will go. But I'm confident the inner basin must refreeze by early November anyway

uniquorn

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Re: The 2019/2020 freezing season
« Reply #218 on: October 10, 2019, 11:42:50 AM »
Could be that Lorenzo's waves took a toll on the Atlantic Ocean side, especially around Svalbard?
Strange to see such a drop on October.
I think the continual export into FJL and Svalbard area over the summer was more unusual. Ice along the atlantic edge has been weakened or melted by sitting over a warm current all that time. Now the drift has temporarily? changed direction it offers little resistance. Yes, it's strange that this has come so late.
unihamburg amsr2-uhh, atlantic side, oct3-9
edit: looking at the forecast, export should resume shortly.
« Last Edit: October 10, 2019, 11:51:02 AM by uniquorn »

gerontocrat

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Re: The 2019/2020 freezing season
« Reply #219 on: October 10, 2019, 12:14:12 PM »
The remaining weeks of October are very important. Normally it should be a century uptick each day. 2019 can delay the fast refreeze because the peripheral seas have the extra heat stored. I'm curious to see how it will go. But I'm confident the inner basin must refreeze by early November anyway
Attached is a graph showing average, 2019 and 2018 extent change from mid Sept to mid-November (JAXA data).

The low 2019 refreeze since minimum is impressive, as was 2018 until now. My guess is that persisting high SST anomalies and +ve Arctic temperature anomalies averaging around +3 for the next week or so will keep refreeze below average for a bit longer - & then zoom up as in 2018 (or maybe not)?
"Para a Causa do Povo a Luta Continua!"
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SimonF92

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Re: The 2019/2020 freezing season
« Reply #220 on: October 10, 2019, 12:55:01 PM »
The remaining weeks of October are very important. Normally it should be a century uptick each day. 2019 can delay the fast refreeze because the peripheral seas have the extra heat stored. I'm curious to see how it will go. But I'm confident the inner basin must refreeze by early November anyway
Attached is a graph showing average, 2019 and 2018 extent change from mid Sept to mid-November (JAXA data).

The low 2019 refreeze since minimum is impressive, as was 2018 until now. My guess is that persisting high SST anomalies and +ve Arctic temperature anomalies averaging around +3 for the next week or so will keep refreeze below average for a bit longer - & then zoom up as in 2018 (or maybe not)?

Lovely figure gerontocrat

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Re: The 2019/2020 freezing season
« Reply #221 on: October 10, 2019, 01:19:45 PM »
The remaining weeks of October are very important. Normally it should be a century uptick each day. 2019 can delay the fast refreeze because the peripheral seas have the extra heat stored. I'm curious to see how it will go. But I'm confident the inner basin must refreeze by early November anyway
Attached is a graph showing average, 2019 and 2018 extent change from mid Sept to mid-November (JAXA data).

The low 2019 refreeze since minimum is impressive, as was 2018 until now. My guess is that persisting high SST anomalies and +ve Arctic temperature anomalies averaging around +3 for the next week or so will keep refreeze below average for a bit longer - & then zoom up as in 2018 (or maybe not)?

Lovely figure gerontocrat
You can see it every day gradually morphing on the Sea Ice Extent & Area Data thread.
"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)

philopek

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Re: The 2019/2020 freezing season
« Reply #222 on: October 10, 2019, 04:59:11 PM »
SIE growth is slowing. Would not surprise me if it stays in 2nd place for a while.

Agree!

My guess is for about 10-14 days max before it becomes lowest again.

<Snipped> currently there is not that much cold enough
water to allow for significant ice-growth, given the right conditions, even a small drop would
be possible
even though not that probably at this time of the year.

BTW a 5-10 days long slow increase, given the melt onset in Antarctica, could see a significant
worsening of the global sea-ice situation as well.


There we went ;)

RoxTheGeologist

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Re: The 2019/2020 freezing season
« Reply #223 on: October 10, 2019, 06:30:49 PM »

My opinion is this season demonstrated that there isn't enough insolation to melt the ice above 80N from a 'normal' freeze season. Too much ice is built up and it doesn't receive enough energy directly from the sun.

For that 4m km2 to melt out there has to be more heat and therefore less ice (duh!). That heat has to come from the atmosphere through the 9 months of the year that insolation isn't dominant, or from the ocean as the result of a big storm or two late in the melt season.

This part of the freeze season is critical, if the seas south of 80N are warm then there will be less Freezing Degree Days over the main pack. Increased water vapor will effect any energy transfer, such as fog over the ice edge preventing both heat loss and the vaporistation/condenstation cycle transferring a lot of energy, and perhaps from snowfall providing insulation to the ice.

It's going to be interesting to watch the next couple of months to see if the thickness of the central pack grows slowly...






Shared Humanity

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Re: The 2019/2020 freezing season
« Reply #224 on: October 10, 2019, 07:30:26 PM »
Could be that Lorenzo's waves took a toll on the Atlantic Ocean side, especially around Svalbard?
Strange to see such a drop on October.
I think the continual export into FJL and Svalbard area over the summer was more unusual. Ice along the atlantic edge has been weakened or melted by sitting over a warm current all that time. Now the drift has temporarily? changed direction it offers little resistance. Yes, it's strange that this has come so late.
unihamburg amsr2-uhh, atlantic side, oct3-9
edit: looking at the forecast, export should resume shortly.

That's not just drift. There is extensive melt happening, most noticeably on the tongue of ice that had extended towards the Barents between FJI and Svalbard. Also along the ice extending south along the coast of Greenland.

HapHazard

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Re: The 2019/2020 freezing season
« Reply #225 on: October 10, 2019, 08:39:40 PM »
I think the continual export into FJL and Svalbard area over the summer was more unusual. Ice along the atlantic edge has been weakened or melted by sitting over a warm current all that time. Now the drift has temporarily? changed direction it offers little resistance. Yes, it's strange that this has come so late.

That's not just drift. There is extensive melt happening, most noticeably on the tongue of ice that had extended towards the Barents between FJI and Svalbard. Also along the ice extending south along the coast of Greenland.
Whether it's [compaction]drift or melt, it does indeed feel a bit late for this & had it happened a month ago the minimum would have been even more interesting.

Eco-Author

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Re: The 2019/2020 freezing season
« Reply #226 on: October 10, 2019, 09:19:36 PM »
Hope it's okay to speculate... I guess a tie with 2012 wasn't out of the question this year at some point, but I've been wondering about how much thicker 2012 ice was compared to 19.  If the ice was  thicker, perhaps it did not 'stick together'* like it seemed to this year instead of deep LONG cracks typical of thicker ice which then more easily separates???

* the ice this year seemed to be sticking together with few long cracks seen on the edges bar N.Greenland... This 'sticking together' of slightly warmer/thinner ice may counteract GAC type weather??? BTW... what's up with Global sea ice?  Challenge 16 for sure!
Self-sufficiency and Durability to disasters are the absolute keys to nearly any disaster you can think of such as War, economic collapse, pandemics, Global warming, quakes, volcanoes, Hurricanes... all of which put solar farms etc. and power grids at risk!

Eco-Author

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Re: The 2019/2020 freezing season
« Reply #227 on: October 10, 2019, 09:35:38 PM »
We have now closed on the time of year, last year, where nine of the last 12 months were spent in the top three and three months broke all kind of new records.  Such a three-year cycle of record lows seems much more like a collapse than a gradual increase melt?   
Self-sufficiency and Durability to disasters are the absolute keys to nearly any disaster you can think of such as War, economic collapse, pandemics, Global warming, quakes, volcanoes, Hurricanes... all of which put solar farms etc. and power grids at risk!

Aluminium

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Re: The 2019/2020 freezing season
« Reply #228 on: October 11, 2019, 08:08:03 AM »
October 6-10.

2018.

Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #229 on: October 11, 2019, 01:13:22 PM »
The third MOSAiC IMB buoy has now gone live, somewhat confusingly named #2:

http://GreatWhiteCon.info/2019/10/facts-about-the-arctic-in-october-2019/#Oct-11

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uniquorn

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Re: The 2019/2020 freezing season
« Reply #230 on: October 11, 2019, 03:42:57 PM »
Given the current SST's it's almost inevitable now that 2019 amsr2-uhh CAB extent will cross the 2012 line(orange), will it cross 2018??(brown)
wipneus CAB regional extent, oct10 https://sites.google.com/site/arcticseaicegraphs/regional

Thomas Barlow

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Re: The 2019/2020 freezing season
« Reply #231 on: October 11, 2019, 03:43:48 PM »
Could get interesting.
2nd lowest extent for this time of year.

http://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/

Paul

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Re: The 2019/2020 freezing season
« Reply #232 on: October 11, 2019, 04:51:31 PM »
Despite the positive AO, sea ice is struggling to form, not too surprising considering the heat intake especially across the ESS and the early ice melt across the Pacific side of the basin and as time goes by, expect this situation to become the norm as the Arctic gets ever warmer.

What is interesting for me however is despite similar results between 2018 and 2019 in terms of a slow refreeze, the weather for both years is completely different. 2018 had a persistent pattern of compacting winds against the ice pack and alot of warm air entering the basin with record breaking temperatures across the Chuckchi I believe, 2019 had an Arctic high in September but barely any WAA however the upper(850) temperatures were quite high and the PV struggling to form. This broken down in October to a more positive AO but ice is struggling to form still.

So all in all and imo, 2019 is showing what we probably expect in the future with a fast melt and very warm temperatures and a slow initial refreeze whereas 2018 slow refreeze was all down to the weather during September and October and if any year experienced that type of weather, then it would of lead to a slow refreeze regardless how much ice there was. Scary thought to think what the extent would be now if we had those conditions in September and October in 2018 this year!

mabarnes

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Re: The 2019/2020 freezing season
« Reply #233 on: October 11, 2019, 05:05:39 PM »
Great graphics, guys.  Amazing how the Atlantic Front receded like that so late in the season, eh.

There's a storm in the Barents ... can't help but stare at it and wonder, what the heck is coming next...!

Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #234 on: October 12, 2019, 11:49:52 AM »
Sea ice extent in the Arctic is now once again “lowest for the date”, since the University of Bremen's AMSRE/AMSR2 based records began at least:

http://GreatWhiteCon.info/2019/10/facts-about-the-arctic-in-october-2019/#Oct-12
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Aleph_Null

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Re: The 2019/2020 freezing season
« Reply #235 on: October 12, 2019, 01:08:40 PM »
Full-size version available in the Nullschool Animations thread:
https://forum.arctic-sea-ice.net/index.php/topic,2905.msg232846.html#msg232846

pressure, wind & density over sea ice concentration
Hindcast: 10/7 to 10/12, Forecast: 10/12 to 10/15.

AMSR2 (U. Bremen sea ice concentration) + MSLP (mean sea level pressure) + IWPD@850hPa (instantaneous wind power density: air density ρ, wind velocity v: ½ρv3) [tiny version]

AndyW

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Re: The 2019/2020 freezing season
« Reply #236 on: October 12, 2019, 04:31:22 PM »
Atlantic side gone from one extreme to another for the start of the freeze season.

Normally freezing from less ice extent helps the accumulation  of ice but it will be interesting to sea how this runs up to December/ January, and then how quickly it melts next year.

The tongue of multiyear ice into the East Siberian Sea  being melted away this summer is probably the big conversation point nobody is talking about ...


philopek

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Re: The 2019/2020 freezing season
« Reply #237 on: October 12, 2019, 11:12:49 PM »
If we are eyeballing DMIs graph over Arctic temperaturen, we should start to see some decent extent gains soon. As Friv has pointed out earlier in another thread we should be very grateful that the melting in ESS was so resistent. Otherwise, the situation would have been a lot worse.

Without saying that we won't see what you suggest, we should still keep in mind that the regions above 80N are mostly ice covered by now and the reminder of the AO is quite warm still.

I personally expect a general delay of about 2-3 weeks from pre-2010 averages.

EDIT: copied/corrected from the data thread because it belongs here ;)

Aluminium

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Re: The 2019/2020 freezing season
« Reply #238 on: October 13, 2019, 07:51:09 AM »
October 8-12.

2018.

oren

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Re: The 2019/2020 freezing season
« Reply #239 on: October 13, 2019, 09:17:59 AM »
October 8-12.
It appears as if extent growth is back at last (check out especially the Atlantic side).

On a more general note, now is the time of year for high growth on the Siberian side. Laptev is the most predictable, with ~600k of area to be added in the next 3 weeks. Kara and ESS are larger, but their timeline is spread over a longer period. The ESS could gain 800k of area in the next 2 weeks (2012) or just 300k in 3 weeks (2016). Kara could gain 500k by the end of October (2015), or just 200k in 5 weeks (2016).
Of course, there's also the CAB, that should have been past its growth stage already. From here on, it could gain 400k of area in 1 week (2012) or 400k in 3 weeks (2018).
Bottom line, area should be picking up fast, around 2.5M in 3 weeks. Gut feeling says it will be slower than most years, but still it should be much faster than the past few weeks.

Ardeus

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Re: The 2019/2020 freezing season
« Reply #240 on: October 13, 2019, 04:27:01 PM »
The IPCC's recently released "Special Report on the Ocean and Cryosphere in a Changing Climate":

https://www.ipcc.ch/srocc/home/

Here's a recording of the associated press conference:



The first 37 mins are rather boring!

And then at 50:00 minutes it gets really exciting when she refers to this paragraph:

"It is very likely that there will be at least one sea-ice free Arctic summer out of 10 years for warming at 2 degrees C, with the frequency decreasing to one sea-ice-free Arctic summer every 100 years at 1.5 degrees C”

What's the reasoning behind this and how does it stand against the trends on the ice volume chart? Saying something like that is just surreal.

Glen Koehler

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Re: The 2019/2020 freezing season
« Reply #241 on: October 14, 2019, 12:52:24 AM »
"It is very likely that there will be at least one sea-ice free Arctic summer out of 10 years for warming at 2 degrees C, with the frequency decreasing to one sea-ice-free Arctic summer every 100 years at 1.5 degrees C”

What's the reasoning behind this and how does it stand against the trends on the ice volume chart?

IPCC is said to be trying to improve their communication skills, but there is still room for improvement. 
RE: "sea-ice free Arctic summer".
   A literal interpretation would be that means zero ASI for every day between June 20 and September 21.
     vs. September average going below 1 million km2 Extent.
     vs.  single day September minimum going below 1 million km2 Extent.
     vs. September as a whole having zero ice.
     vs.  single day September minimum having zero ice.

So which is it?  More precise specification of dates and definition of terms for statements about future ice losses would greatly improve clarity and reduce confusion about what is being said.

Speaking of confusion, this discussion belongs in the "When will the Arctic Go Ice Free" thread, not this one.
« Last Edit: October 14, 2019, 01:21:20 AM by Glen Koehler »

Thomas Barlow

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Re: The 2019/2020 freezing season
« Reply #242 on: October 14, 2019, 03:24:46 AM »
Sea-ice thickness looks exceptionally bad just now (bottom right).
This does not bode well for rapid extent recovery when the extent is 2nd lowest on record for this time of year, and closing in on lowest.

Comparing years.

http://polarportal.dk/en/sea-ice-and-icebergs/sea-ice-thickness-and-volume/#c23629
« Last Edit: October 14, 2019, 03:31:35 PM by Thomas Barlow »

grixm

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Re: The 2019/2020 freezing season
« Reply #243 on: October 14, 2019, 08:20:35 AM »

El Cid

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Re: The 2019/2020 freezing season
« Reply #244 on: October 14, 2019, 08:36:59 AM »
Compaction is extreme, so there is no easy to freeze ice; SSTs are way above anything I have seen before, and there is warmer than average air over the Arctic the next few days. I would say that it is likely that 2019 will get to the first place some time October. Refreeze should be very very slow.
Or the Arctic will trick me again as it usually does :)

...and amazingly I got this one right! Even I am surprised :)

And amazingly, SSTs are still way above the lowest extent years (2007,12,16) on the Pacific Side, although colder on the Atlantic side (see attached pic). Refreeze should still be very slow

SimonF92

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Re: The 2019/2020 freezing season
« Reply #245 on: October 14, 2019, 11:57:05 AM »
Conditions in pretty much the entire Russian side of the Arctic are terribly warm at the moment. I don't see any real indication that a catch-up will be happening soon either.

There is evidence of a refreeze beginning in the Laptev but it is likely to be anaemic and limited to the coast.

Aluminium

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Re: The 2019/2020 freezing season
« Reply #246 on: Today at 08:21:32 AM »
October 10-14.

2018.

Aleph_Null

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Re: The 2019/2020 freezing season
« Reply #247 on: Today at 01:52:01 PM »
Full-size version available in the Nullschool Animations thread:
https://forum.arctic-sea-ice.net/index.php/topic,2905.msg233143.html#msg233143

pressure, wind & density over sea ice concentration
Hindcast: 10/10 to 10/15, Forecast: 10/15 to 10/18.

AMSR2 (U. Bremen sea ice concentration) + MSLP (mean sea level pressure) + IWPD@850hPa (instantaneous wind power density: air density ρ, wind velocity v: ½ρv3) [tiny version]