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BornFromTheVoid

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Re: The 2020 melting season
« Reply #6150 on: September 16, 2020, 07:34:48 PM »
Today's images and animation (a little delayed!)

I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

BornFromTheVoid

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Re: The 2020 melting season
« Reply #6151 on: September 16, 2020, 07:52:03 PM »
Open water pushing closer to the N. Pole again. ~492 km away near Severnaya Zemlya and 504 km, N. of Franz Joseph Land
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Burnrate

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Re: The 2020 melting season
« Reply #6152 on: September 16, 2020, 07:56:37 PM »
Open water pushing closer to the N. Pole again. ~492 km away near Severnaya Zemlya and 504 km, N. of Franz Joseph Land

It's crazy how balanced the extent is.  Still losing a tiny bit every day but such small changes when it looks like a lot is going on.

glennbuck

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Re: The 2020 melting season
« Reply #6153 on: September 16, 2020, 10:39:25 PM »
The CAB 16th September, North Pole area blanked out since 14th of September and larger areas blanked out on the 15th and 16th, not sure why.

Csnavywx has the answer below

The setting of the polar sun is why those areas get blanked out. Insufficient light or too attenuated by extreme angle to produce a good image.
« Last Edit: September 16, 2020, 10:57:38 PM by glennbuck »

Csnavywx

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Re: The 2020 melting season
« Reply #6154 on: September 16, 2020, 10:49:45 PM »
The setting of the polar sun is why those areas get blanked out. Insufficient light or too attenuated by extreme angle to produce a good image.

uniquorn

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Re: The 2020 melting season
« Reply #6155 on: September 16, 2020, 11:12:06 PM »
Wipneus' regional extent chart for the CAB suggests there has been a physical limit for latest refreeze set by 2012. 2018 and 2019 tending to confirm that limit. 2020 is close to testing it.
« Last Edit: September 16, 2020, 11:49:08 PM by uniquorn »

Neven

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Re: The 2020 melting season
« Reply #6156 on: September 16, 2020, 11:59:40 PM »
Looks to me like it's safe to call the minimum.
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be cause

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Re: The 2020 melting season
« Reply #6157 on: September 17, 2020, 12:30:41 AM »
 .. I'll wait 'till Sally's had her say ..

 .. forecast from a few days ago ..
https://modeles.meteociel.fr/modeles/gfs/runs/2020091406/gfsnh-0-252.png?6
 
 .. and tonight ..
https://modeles.meteociel.fr/modeles/gfs/runs/2020091618/gfsnh-0-192.png?18

  .. there may yet be a very big sting in the tale ( of 2020 ) ..  ;) .. b.c.

 p.s. btw .. Test space is well worth a visit to see Uniquorn's adaptation of seaice.de's post upthread ^ .

 

« Last Edit: September 17, 2020, 01:11:38 AM by be cause »
2007 + 5 = 2012 + 4 = 2016 + 3 = 2019 + 2 = 2021 
 (phew)

Paul

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Re: The 2020 melting season
« Reply #6158 on: September 17, 2020, 01:15:29 AM »
Still looks like the Beaufort sea could see rapid regrowth, todays worldview image confirms alot of thin ice either forming or perhaps remaining from the melt season and if temperatures do drop there(which seems fairly likely) it should not take much for true new ice to form.

Then contrast to the Laptev sea which has seen no cold so far this month, its bound to be record breaking here for regrowth, could see open water there still by the start of December at this rate.

Freegrass

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Re: The 2020 melting season
« Reply #6159 on: September 17, 2020, 02:42:36 AM »
Looks to me like it's safe to call the minimum.

I agree. I think it's over...
I'm surprised nobody opened a new freezing thread yet. So here you go...

https://forum.arctic-sea-ice.net/index.php/topic,3299.0.html
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Re: The 2020 melting season
« Reply #6160 on: September 17, 2020, 03:19:54 AM »
AMSR2: Some recent days of 2020 compared to 2012
These animations of the two years look eerily similar to my inexpert eye.  I was quite startled.  I have to remind myself, as we all that get wrapped up in numbers, that extent and area values are just indicators of melt, the best guides we have to the melting season, but not perfect ones.  In terms of ice extent and distribution, there is not much to distinguish the two years in broad terms.  Your animation made me reset my perspective a bit: that 2021 will start in roughly the same position as 2013, but with a warmer planet and a warmer Arctic Ocean.

Of course there are other differences, but I am (maybe simplistically) going for the big picture here.
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oren

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Re: The 2020 melting season
« Reply #6161 on: September 17, 2020, 03:20:00 AM »
Thanks FG, let the thread stand but I prefer posts go into the melting season thread for the next couple of days. NSIDC area is still making new lows for the year, and I'd rather wait for the mid-Sep PIOMAS update on the 19th.

Aluminium

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Re: The 2020 melting season
« Reply #6162 on: September 17, 2020, 05:47:48 AM »
September 12-16.

2019.

jdallen

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Re: The 2020 melting season
« Reply #6163 on: September 17, 2020, 08:05:06 AM »
Thanks FG, let the thread stand but I prefer posts go into the melting season thread for the next couple of days. NSIDC area is still making new lows for the year, and I'd rather wait for the mid-Sep PIOMAS update on the 19th.
Agree.  Don't think it's quite done yet.

Don't think it will challenge 2012, but, I think the fact it is still "uncertain" is important and relevant.

That we *don't* have a definitive switch over to a refreeze I think is very significant.
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Sepp

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Re: The 2020 melting season
« Reply #6164 on: September 17, 2020, 09:42:02 AM »
The low concentration areas inside the CAB of yesterday’s AWI concentration map are well observable in the corresponding World View due to clear sky.

BornFromTheVoid

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Re: The 2020 melting season
« Reply #6165 on: September 17, 2020, 12:44:18 PM »
Today's images and animation.
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

uniquorn

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Re: The 2020 melting season
« Reply #6166 on: September 17, 2020, 01:01:16 PM »
AMSR2: Some recent days of 2020 compared to 2012
Rough overlay of 2012 vs 2020 using awi amsr2 v103, aug20-sep15 (am/pm)

gimp grain extract, the years were slightly different sizes so there is a small scaling error
« Last Edit: September 17, 2020, 01:09:46 PM by uniquorn »

Burnrate

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Re: The 2020 melting season
« Reply #6167 on: September 17, 2020, 02:53:36 PM »
NSIDC finally has the 5 day daily extent change going positive.  It seems like a pretty strong trend at this point.

Freegrass

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Re: The 2020 melting season
« Reply #6168 on: September 17, 2020, 03:30:29 PM »
Latest Five Day Forecast
Wind @ Surface + Total Precipitable Water
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Re: The 2020 melting season
« Reply #6169 on: September 17, 2020, 03:40:04 PM »
BFTV...

Very clear evidence of ice forming in that first image...the melt season looks like it's over with regards to SIE and Area. Would volume continue to decline for a while?

Tom_Mazanec

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Re: The 2020 melting season
« Reply #6170 on: September 17, 2020, 04:18:34 PM »
The scary thing is that we keep being the record “normal” year even if we don’t beat the abnormal 2012.
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Re: The 2020 melting season
« Reply #6171 on: September 17, 2020, 04:37:18 PM »
That's a great visual uniquorn. You succeeded imo. Perhaps a different colour scheme, but that's a personal taste.

A storm is still not out of the question, to extend the melting season.
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UCMiami

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Re: The 2020 melting season
« Reply #6172 on: September 17, 2020, 04:40:43 PM »
Uniquorn
Great graphic.
It looks to me that the extent losses are over and maybe area losses as well because new ice is forming around greenland and the caa, but the ESS, the Beaufort, and even some of the Atlantic front may continue to lose ice extent/area. And volume loses may continue for a week or two until surface water temperature truly drops.

gerontocrat

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Re: The 2020 melting season
« Reply #6173 on: September 17, 2020, 04:55:25 PM »
NICO Sun's graph uses NSIDC daily area which as of 16 Sept is 2.583 million km2, some 58k km2 less than the 16 Sept 5 day trailing average of 2.641 million km2. So 5-day trailing average area loss will probably keep going for at least a couple of days longer.
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Glen Koehler

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Re: The 2020 melting season
« Reply #6174 on: September 17, 2020, 07:07:48 PM »
AMSR2: Some recent days of 2020 compared to 2012
Rough overlay of 2012 vs 2020 using awi amsr2 v103, aug20-sep15 (am/pm)

gimp grain extract, the years were slightly different sizes so there is a small scaling error
     Nice graphic uniquorn.
     FWIW - Perhaps the difference between 2020 and 2012 can be summarized as:
                 
      Where 2020 had ice at minimum beyond the 2012 extent, that 2020 ice was thin, fractured, "low quality" (in terms of melt resistance).  Though I suppose the same could be said about the reverse, i.e. where 2012 had ice but 2020 didn't, that peripheral ice in 2012 was hardly pristine.
               
      And where both years had ice in the CAB, a good chunk of the 2020 CAB ice is in a weakened state, whereas in 2012 the central CAB was still pretty much the continuous, thicker (than 2020) ice pack of the pre-21st century Arctic which is no more.
               
« Last Edit: September 18, 2020, 07:39:52 PM by Glen Koehler »

aslan

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Re: The 2020 melting season
« Reply #6175 on: September 17, 2020, 09:42:24 PM »
It's not just a SST thing in the Barents, Kara and Laptev seas. The heat goes town to 30m or more. Compare the 30 m Arctic temperatures of this year with 2019 on Mercator ocean and you will see that there's much more ocean heat on the Atlantic side this year than last. On the other hand, there's less heat on the Pacific side. Over both sides, there's much more heat this year, but there is almost always a see saw effect in the Arctic between the Atlantic and Pacific.

It is too bad we don't have buoy. With melt still ongoing noth of 85°N it is looking like that the halocline has taken a hit and Atlantic layer is pushing upward. Salinity at surface is higher than in 2019 also, implying a reduced stability. The high salinity is also to be compared to the high freshwater input this year.

Freegrass

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Re: The 2020 melting season
« Reply #6176 on: September 17, 2020, 09:56:20 PM »
     Nice graphic uniquorn.
     FWIW - Perhaps the difference between 2020 and 2012 can be summarized as:<snip>
2012 had a GAC
2020 had a GAAC

The GAC gave us a minimum below 4 million m2 because of wind
The GAAC gave us a minimum below 4 million m2 because of heat and salt (and a little bit of wind)

2012 was a false BOE 0.1
2020 was a real BOE 0.2

Some people say a BOE is below 1 million m2
Others say a BOE is below 4 million m2

To end that argument, let's call everything in between 1M m2 and 4M m2 a BOE 0.x...

Does anyone doubt that 2020 was a paradigm shift?
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oren

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Re: The 2020 melting season
« Reply #6177 on: September 17, 2020, 10:18:40 PM »
I see it differently, I think both years were eventually quite similar, when using generalizations:
2012 was sunny and warm and then windy and very stormy. It had some extra fluffy ice in the ESS but eventually it melted that ice and was left with a compact pack (and an extent record).
2020 too was sunny and warm and then very windy and somewhat stormy. It had some extra fluffy ice in the Chukchi and Siberian facing sections of CAB,  but eventually most of it melted and it was left with a mostly compact pack - except in the CA and the Beaufort arm (and a 2nd place extent finish).

jdallen

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Re: The 2020 melting season
« Reply #6178 on: September 17, 2020, 10:22:29 PM »
     Nice graphic uniquorn.
     FWIW - Perhaps the difference between 2020 and 2012 can be summarized as:<snip>
<snip>
Does anyone doubt that 2020 was a paradigm shift?
This ain't your grandma's arctic anymore!

Actually, I'd say the "flip" happened between 2007 & 2012.  Since then, I think we've just been working through latency in the system.
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Glen Koehler

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Re: The 2020 melting season
« Reply #6179 on: September 17, 2020, 10:31:56 PM »
Actually, I'd say the "flip" happened between 2007 & 2012.  Since then, I think we've just been working through latency in the system.
      The 2012 GAC gets lots of attention, which is justified for a freak event with high (though much of it shortlived) impact.  But I haven't seen as much discussion about the weather patterns that had already defined 2012 as a big melt year well before the GAC 2012. 

      Agreed, 2007 really was the starting gun. The more I've learned the more I've wondered "What the heck happened in 2007?"  ASI watchers must have been freaking out at the time because there were no precedents or early warning as far as I can tell.  It was a killer melt year from which the Arctic has never really recovered.  Discussion of the weather patterns or other factors that made 2007 such a drastic melt year would be appreciated by this reader, and I suspect many other ASIF denizens.
     
« Last Edit: September 17, 2020, 10:39:07 PM by Glen Koehler »

kassy

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Re: The 2020 melting season
« Reply #6180 on: September 17, 2020, 10:59:20 PM »
https://earthobservatory.nasa.gov/images/8074/record-arctic-sea-ice-loss-in-2007

This is what it looked like.

Somewhere along the 07-12 years the ice rebuilding circulation broke down. Not that much thick ice making the Beaufort round to join the pack.

I think 2007 was just a year on a continuum. Back then it looked bad but there still was a lot of ice.
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Niall Dollard

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Re: The 2020 melting season
« Reply #6181 on: September 18, 2020, 12:22:02 AM »
Quote
      Agreed, 2007 really was the starting gun. The more I've learned the more I've wondered "What the heck happened in 2007?"  ASI watchers must have been freaking out at the time because there were no precedents or early warning as far as I can tell.  It was a killer melt year from which the Arctic has never really recovered.  Discussion of the weather patterns or other factors that made 2007 such a drastic melt year would be appreciated by this reader, and I suspect many other ASIF denizens.
     

I cant locate where, Glen but I remember Friv posting numerous times earlier this year about the remarkable dipole summer of 2007.

I suppose everyone here has their own perspective on the Arctic. Their own moment/year which really stands out.

I'll throw in my list:

1975 - Wasnt old enough in '75 but about 20 years ago I remember first reading from the Canadian Ice Service that the shipping channels to Prudhoe Alaska were blocked all through that summer.

2007 - Was a huge wake up. I used to get my Arctic data from the NSIDC and remember seeing the images that September  and being so amazed how far the ice had eroded especially on the Pacific side. It was an unusual profile as ice was still connected to Russia near the north Cape.

2012 - The GAC and my first becoming aware of Neven's blog.

2016 - The state of the ice all around the pole that August/Sept was so bad. Looked even worse (in that area) than this year.

2020 - The large melt this year was not a surprise to me, given the starting conditions last April. However the thinning north of Greenland was an eye opener. Yet another big Arctic surprise.

What strange/surprises await us next year ?

Best place to watch it all unfold is the ASIF. Thanks to all !

Paul

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Re: The 2020 melting season
« Reply #6182 on: September 18, 2020, 12:35:44 AM »
Actually, I'd say the "flip" happened between 2007 & 2012.  Since then, I think we've just been working through latency in the system.
      The 2012 GAC gets lots of attention, which is justified for a freak event with high (though much of it shortlived) impact.  But I haven't seen as much discussion about the weather patterns that had already defined 2012 as a big melt year well before the GAC 2012. 

      Agreed, 2007 really was the starting gun. The more I've learned the more I've wondered "What the heck happened in 2007?"  ASI watchers must have been freaking out at the time because there were no precedents or early warning as far as I can tell.  It was a killer melt year from which the Arctic has never really recovered.  Discussion of the weather patterns or other factors that made 2007 such a drastic melt year would be appreciated by this reader, and I suspect many other ASIF denizens.
     

2007 was dominated by a Beaufort high for the large part hence a tongue of ice compacted against the Arctic islands in the Laptev sea. Either way, persistent southerly and very warm winds kept on compacting the ice leaving more and more open water in the ESS and Chukchi sea and I've no doubt the warm SSTS contributed the ice edge reaching 85 degrees north. Compare 2006 to 2007 and it was eye opening just how much difference there was between the two years especially on the Pacific side of the basin.

This year was similar especially in July but the positioning of the high was more in the ESS region hence the Laptev sea had very rapid melt but thinner than average ice certainly played a role also.

What the high pressure does do though is compact the CAB ice which means ice conditions to that of 2010, 13 and 16 less likely but as this year is showing, there is only so much compaction and warmth the CAB ice can take before its start to retreat away. Its why I did not believe we would see record lows this year but extent did drop a bit lower than I expected because of the huge retreat in the CAB sector.

gandul

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Re: The 2020 melting season
« Reply #6183 on: September 18, 2020, 12:53:32 AM »
I see it differently, I think both years were eventually quite similar, when using generalizations:
2012 was sunny and warm and then windy and very stormy. It had some extra fluffy ice in the ESS but eventually it melted that ice and was left with a compact pack (and an extent record).
2020 too was sunny and warm and then very windy and somewhat stormy. It had some extra fluffy ice in the Chukchi and Siberian facing sections of CAB,  but eventually most of it melted and it was left with a mostly compact pack - except in the CA and the Beaufort arm (and a 2nd place extent finish).
I agree, only to stress that 2012 was an outlier and 2020 is almost normal as the global warming goes on.
Also I don’t see a paradigm shift at all, just a continuation of a warmer planet due to CO2. The ice is basically the same, only a lot less.

uniquorn

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Re: The 2020 melting season
« Reply #6184 on: September 18, 2020, 01:09:19 AM »
I see it differently, I think both years were eventually quite similar, when using generalizations:
2012 was sunny and warm and then windy and very stormy. It had some extra fluffy ice in the ESS but eventually it melted that ice and was left with a compact pack (and an extent record).
2020 too was sunny and warm and then very windy and somewhat stormy. It had some extra fluffy ice in the Chukchi and Siberian facing sections of CAB,  but eventually most of it melted and it was left with a mostly compact pack - except in the CA and the Beaufort arm (and a 2nd place extent finish).
I agree, only to stress that 2012 was an outlier and 2020 is almost normal as the global warming goes on.
Also I don’t see a paradigm shift at all, just a continuation of a warmer planet due to CO2. The ice is basically the same, only a lot less.
I agree too and would add that, with less ice, the arctic ocean is beginning to show itself more. Last year the CAA crack and this year the Greenland gap.

Pagophilus

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Re: The 2020 melting season
« Reply #6185 on: September 18, 2020, 02:37:29 AM »
I see it differently, I think both years were eventually quite similar, when using generalizations:
2012 was sunny and warm and then windy and very stormy. It had some extra fluffy ice in the ESS but eventually it melted that ice and was left with a compact pack (and an extent record).
2020 too was sunny and warm and then very windy and somewhat stormy. It had some extra fluffy ice in the Chukchi and Siberian facing sections of CAB,  but eventually most of it melted and it was left with a mostly compact pack - except in the CA and the Beaufort arm (and a 2nd place extent finish).

I agree, only to stress that 2012 was an outlier and 2020 is almost normal as the global warming goes on.
Also I don’t see a paradigm shift at all, just a continuation of a warmer planet due to CO2. The ice is basically the same, only a lot less.
I agree too and would add that, with less ice, the arctic ocean is beginning to show itself more. Last year the CAA crack and this year the Greenland gap.
Agreed with all the above.  And this may make this the most 'agreeable' post of the entire melting season.  Just want to add that a paradigm shift, at least as defined by Kuhn, refers to a fundamental shift in the way a system is perceived or modeled, here by scientists.  Crossing a threshold refers to a system changing relatively quickly internally, and then operating in a qualitatively different way.  In a hundred years, scientists may look back at, say, 2007 and say, yup, that was the year the Arctic flipped, or they may prefer to state that the threshold began to be crossed in 2007, and that the threshold was fully crossed over the next couple of decades.  Hard to tell when you are in the middle of things. Had to check up on that terminology, BTW, didn't remember it fully.
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oren

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Re: The 2020 melting season
« Reply #6186 on: September 18, 2020, 03:12:18 AM »
Here is a chart and table I prepared earlier this year based on PIOMAS volume data that I never got around to posting in the PIOMAS thread. Now that the season is over and discussion of 2007 has come up, I will indulge in digressing.
It is a well known fact that 2007 summer was very bad for the ice. However, when checking relative volume performance in the chart, it appears most of the damage was done in Oct-Dec 2006, when the Arctic failed to gain enough volume compared to other years. I am not sure what happened weather-wise or export-wise, but if anyone can shed light on this anomaly it would be welcome.
As the table shows, 2007 had the highest late summer loss, but in terms of magnitude this pales compared to its lowest preceding winter gain. Note the bold numbers are the highest and lowest per period excluding 2007.

Click to enlarge.

Freegrass

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Re: The 2020 melting season
« Reply #6187 on: September 18, 2020, 05:57:18 AM »
I see it differently, I think both years were eventually quite similar, when using generalizations:
2012 was sunny and warm and then windy and very stormy. It had some extra fluffy ice in the ESS but eventually it melted that ice and was left with a compact pack (and an extent record).
2020 too was sunny and warm and then very windy and somewhat stormy. It had some extra fluffy ice in the Chukchi and Siberian facing sections of CAB,  but eventually most of it melted and it was left with a mostly compact pack - except in the CA and the Beaufort arm (and a 2nd place extent finish).

I agree, only to stress that 2012 was an outlier and 2020 is almost normal as the global warming goes on.
Also I don’t see a paradigm shift at all, just a continuation of a warmer planet due to CO2. The ice is basically the same, only a lot less.
I agree too and would add that, with less ice, the arctic ocean is beginning to show itself more. Last year the CAA crack and this year the Greenland gap.
Agreed with all the above.  And this may make this the most 'agreeable' post of the entire melting season.  Just want to add that a paradigm shift, at least as defined by Kuhn, refers to a fundamental shift in the way a system is perceived or modeled, here by scientists.  Crossing a threshold refers to a system changing relatively quickly internally, and then operating in a qualitatively different way.  In a hundred years, scientists may look back at, say, 2007 and say, yup, that was the year the Arctic flipped, or they may prefer to state that the threshold began to be crossed in 2007, and that the threshold was fully crossed over the next couple of decades.  Hard to tell when you are in the middle of things. Had to check up on that terminology, BTW, didn't remember it fully.
The paradigm shift (maybe a little exaggeration) I was talking about is not only coming from the weather, but from the salt as that research paper pointed out. Heat is coming from below now. And I bet that all the energy that went into the open ocean in Juli was transferred to deeper layers in the next two months.

Another big event this season was the mega crack and the loss of thick MYI along the North American Arctic Coast. I think that 2020 was the last year for thick MYI because of the heat that's coming from below now. The last of the thick ice will face it's doom in the Beaufort next season, and I don't see how this can be restored when expectation is thinner ice...
If every 8 year old in the world is taught meditation, we will eliminate violence from the world within one generation.
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Glen Koehler

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Re: The 2020 melting season
« Reply #6188 on: September 18, 2020, 06:04:09 AM »
 
Here is a chart and table I prepared earlier this year based on PIOMAS volume data... <snip>
   
     Wow, Oren.  2007 is jaw dropping.  I mean, really.  If any of the experts are lurking around the ASIF this is the time to show your cards.  Calling Drs. Alley, Birkel, Box, Dethloff, Goose, Meier, Notz, Mayewski, Overland, Polyak, Scambos, Serreze, Shuppe, Stroeve, Wadhams, Zhang, and all the rest.  WTF, call Dr. Ruth too.  Sadly, Dr. Konrad Steffen is off-duty. 

      You can weigh in under a pseudonym if association with this scruffy lot is hazardous to your professional reputation.  Dr. A-Team, please report to the operating room!  Patient #2007 lost weight all winter and suffered heavy bleeding all summer!  We need a diagnosis.
     
     Assuming minimum Volume in 2020 will be no higher than 2019, a quick trip to Excel suggests that the Late Summer 2020 melt was ca. 9.02 M km3 which would be a new record, leaving 2012 in the dust (for that period). 

     ...and that the 2020 Summer Total melt would be ca. 19.01 Mkm3, just 0.26M short of 2012.  All that from an impressive GAAC and a short-lived semi-GAC in 2020, but without any lightening strikes like the GAC 2012.

     With the day 266 to 266 framing, 2012 takes a step back, and 2016 a step forward.  But 2007 is revealed to be a Monster Performance.  It was like Tiger Woods at the 1997 Masters Tournament just crushing the competition.  (That was more than golf, it was a great day for humankind at a private club that barred black golfers until 1975, but I digress...)

     I'm going to have to go back and re-read those Friv dipole posts from this summer.  Now I know why Neven, Friv and others get so itchy when it looks like a dipole might set up. 
Maybe we need a new Glossary entry:  Dipole = Atmospheric Ice Eating Monster. 
« Last Edit: September 18, 2020, 07:34:41 AM by Glen Koehler »

I’M IN LOVE WITH A RAGER

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Re: The 2020 melting season
« Reply #6189 on: September 18, 2020, 07:49:16 AM »
Based on the quite low 2016-2017 freezing season maximum which I would hypothesize was at least partially due to the state of the 2016 minimum, is it plausible to expect that similar effects, albeit maybe not as extreme, could be observed this freezing season as well due to the extensive damage to the CAB in both years and the high SSTs in the peripheral seas (especially the W Siberian ones)? I get the feeling it’s going to be an uphill battle for some areas which do not usually see that problem to such a degree to refreeze enough in time to not be crippled as the melting season rears its head once again in 2021. Thin ice (low volume compared to resulting extent, which may also be low) and warmer SSTs/higher salinity might be the “new paradigm”/“dynamic shift” that 2020 is kickstarting/propagating.

El Cid

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Re: The 2020 melting season
« Reply #6190 on: September 18, 2020, 09:00:14 AM »
As for 2006/7 low volume buildup:

I do not know the answer, but I know that 2006/7 was the warmest winter in Europe and Russia. I attach a comparison of 2006/7 winter vs the (otherwise warmest decade of winters of) 2010-2020.

Simon

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Re: The 2020 melting season
« Reply #6191 on: September 18, 2020, 09:13:43 AM »
Oren’s figures are very interesting. Seems that seasonal ice loss is 17.5 x 1000km3 +/_ 10%. We will have to wait till the late September volume result is in but it is likely that 2020 may become the 2nd largest volume loss of recent years.

One may like to speculate that a potential BOE (however defined) may need a precondition of a maximum ice volume below 20 x 1000 km3

BornFromTheVoid

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Re: The 2020 melting season
« Reply #6192 on: September 18, 2020, 11:03:36 AM »
Today's images and animation. There can be little doubt now that the passed the minimum, as gains in the Beaufort Sea easily outweigh any changes elsewhere.
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

F.Tnioli

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Re: The 2020 melting season
« Reply #6193 on: September 18, 2020, 12:43:55 PM »
... Patient #2007 lost weight all winter and suffered heavy bleeding all summer!  We need a diagnosis.
 ...
Untreated AA, prodromal phase.
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!

nanning

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Re: The 2020 melting season
« Reply #6194 on: September 18, 2020, 04:48:55 PM »
In the same metaphore:
The symptoms are worsening fast. I fear the patient is already in the terminal phase ;)
(dunno what "AA" means)

What will next year bring? I can't wait to see the patient die.

The continued living of this patient is frustrating climate action because it takes too long for the population at large to unmistakenly see clear consequences and get really fearfull. In an existential emergency one should be fearful if one wants to live.
The sooner we 'stop', the better for life on Earth. At least for the children's future.
The emergency signs were flashing in our eyes. Bye bye.
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be cause

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Re: The 2020 melting season
« Reply #6195 on: September 18, 2020, 05:04:05 PM »
''Fear not !'' said he , for mighty dread had seized their troubled minds .. b.c.
2007 + 5 = 2012 + 4 = 2016 + 3 = 2019 + 2 = 2021 
 (phew)

Neven

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Re: The 2020 melting season
« Reply #6196 on: September 18, 2020, 07:33:35 PM »
This is the best thread on the Internet. Thanks, everyone.
Il faut comparer, comparer, comparer, et cultiver notre jardin

morganism

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Re: The 2020 melting season
« Reply #6197 on: September 18, 2020, 10:40:52 PM »
I still think its the methane release that is causing the wild melt outs. wonder if the alkalinity affects the methanogens and methanotrophs, as much as the extra carbon afffects the algeas.


Extreme Greenland blocking and high‐latitude moisture transport
https://rmets.onlinelibrary.wiley.com/doi/full/10.1002/asl.1002

https://en.wikipedia.org/wiki/Ridiculously_Resilient_Ridge

https://www.wunderground.com/cat6/Methane-Giving-Noctilucent-Clouds-Boost

https://www.theguardian.com/environment/2014/feb/10/bottom-trawling-how-to-empty-the-seas

Has been a weird few years, and a big thanks to all those folks doing the charts and comparison gifs.
Have been informative on ocean and ice matters to a life-long desert rat.

I’M IN LOVE WITH A RAGER

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Re: The 2020 melting season
« Reply #6198 on: September 18, 2020, 10:58:39 PM »
This is the best thread on the Internet. Thanks, everyone.

Couldn’t have the best thread without the best forum on the internet :)
Thanks for keeping this place running and well managed so long Neven, as well as Oren and everyone else. The participation and knowledge contributions from all the users+moderators make it a great experience to be a part of! Although this may be the end of the melt season, I’m sure this one will be talked about for quite awhile. It’s been great discussing it in real time with all of you!

Pagophilus

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Re: The 2020 melting season
« Reply #6199 on: September 18, 2020, 11:48:14 PM »
This is the best thread on the Internet. Thanks, everyone.

Neven, I join many others in thanking you for hosting us and making all this possible, and thanking Oren also for his excellent moderation.  This is such a valuable service to us as individuals.  You provide vital leadership in spreading understanding of what is happening to our beleaguered planet.
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