The 2020 melting season

[Thomas Barlow]

<snip, N.>
And does "go to the DMI thread" mean...

<Snip. It means 'go to the DMI thread' to discuss DMI volume maps and charts. It is well-known that DMI and HYCOM volume maps and graphs should be taken with large grains of salt, as very little is known about their respective methodologies. So, I'd like to ask everyone not to post too much about their results, so as not to mislead people into thinking that these are hard measurements showing things that are not actually happening. Thanks, N.>

[wili]

gandul wrote: "I am an ass"

Shakespeare wrote: "Man is but an ass..."

<Sorry YT vid removed. O>

[Burnrate]

Some waves in Chukchi sea in about 5-6 days... interesting

Six day forecast, ugh.  Even 3 days out can't seem to give an idea of what is going to happen.  It's such a mess up there right now.

[Freegrass]

Latest Five Day Forecast
Wind @ Surface + Total Precipitable Water
Large GiF!

Sorry I'm a little late. I was too busy with that Olivine webinar.

[Freegrass]

Latest Five Day Forecast
Wind @ Surface
Wind + Temp @ 850hPa
Large GiFS!

A mess is coming up above the Fram, will it happen this time? It does seem so.

...overall I think the damage will be minimal. Some ice will move and big floes will break up I guess, but it won't be the disaster that it could have been.

I think I need to correct this. The wind is a little stronger again on the latest forecast, so there could be some significant damage to the ice north of Nares. We'll know soon enough...

[Burnrate]

...
  And does "go to the DMI thread" mean you'll delete this, after you got your opinion in there first. No-one else's allowed.
...

If you disagree with someone state it, and your reasons and evidence.  Don't try to attack them personally for any reason.  It's well established that discussions on specific topics, such as specific model accuracy, don't belong in the melting season thread.

Since you seem to have not read most of this years thread (or previous years) maybe give that a go to see what people have said about these things.

[gandul]

Some waves in Chukchi sea in about 5-6 days... interesting

Six day forecast, ugh.  Even 3 days out can't seem to give an idea of what is going to happen.  It's such a mess up there right now.

3-meter waves in Amundsen Gulf ? ? ? Per windy.tv which uses ecmwf.
Will be choppy in and around the Beaufort appendix. But yeah even 5th day forecast is pretty uncertain nowadays

[Sebastian Jones]

I'd like to commend BornFromTheVoid on their stunning 3 day slow gif upthread. It is mesmerizing to watch the ice drift and fade, almost like being there in real (but sped up) time. Clearly you have taken a tremendous amount of time and considerable skill and talent to produce this. I don't want to be greedy, but this is exactly how I'd like to view retrospectives of melting seasons.

[jdallen]

Some waves in Chukchi sea in about 5-6 days... interesting

Six day forecast, ugh.  Even 3 days out can't seem to give an idea of what is going to happen.  It's such a mess up there right now.

3-meter waves in Amundsen Gulf ? ? ? Per windy.tv which uses ecmwf.
Will be choppy in and around the Beaufort appendix. But yeah even 5th day forecast is pretty uncertain nowadays

So far, the forecasts I've seen posted suggest most of the upcoming storm's wrath (both Pacific and Atlantic side) is going to be expended on what is already open water.

We may see waves of unusual size in both, but it seems like the highest pressure gradients are missing the ice edge for the most part.

[Freegrass]

Latest Five Day Forecast
Wind + Temp @ Surface
Large GiF!

[BornFromTheVoid]

Latest images. The losses on the Laptev/Kara/Barents region have picked up, as expected with the southerly winds. Quite variable elsewhere.
Slow animation of change from the 23rd to the 26th too.

[ArcticMelt2]

Why is JAXA seeing such low ice loss? According to NSIDC and the University of Bremen, the losses are much higher and the difference from 2012 is smaller.

[BornFromTheVoid]

Why is JAXA seeing such low ice loss? According to NSIDC and the University of Bremen, the losses are much higher and the difference from 2012 is smaller.

Daily NSIDC extent is over half a million km2 more than 2012, so pretty much in line with JAXA

[Jim Hunt]

Daily NSIDC extent is over half a million km2 more than 2012, so pretty much in line with JAXA

However the gap with 2012 is much smaller if you look at AWI/Bremen extent instead:

https://www.meereisportal.de/en/

[BornFromTheVoid]

However the gap with 2012 is much smaller if you look at AWI/Bremen extent instead:

https://www.meereisportal.de/en/

Yep, so it seems the Bremen data is the odd one out. Though the updated extent has moved more inline with the other two.

[ArcticMelt2]

Yep, so it seems the Bremen data is the odd one out. Though the updated extent has moved more inline with the other two.

As I understand it, the difference is that the data from the University of Bremen have a much higher resolution.

The University of Bremen uses a resolution of 6.25 km, NSIDC 25 km.

About JAXA talk about 10 km.

https://svs.gsfc.nasa.gov/4684

Two JAXA datasets used in this animation are the 10-km daily sea ice concentration and the 10 km daily 89 GHz Brightness Temperature.

So the chances of breaking the 2012 record are growing.

[Jim Hunt]

As I understand it, the difference is that the data from the University of Bremen have a much higher resolution.

And here too is Wipneus's metric derived from the University of Hamburg's 3.125 km grid AMSR2 data! Chapter and verse over at:

https://GreatWhiteCon.info/2020/08/the-2020-arctic-sea-ice-minimum-extent/

[Jim Hunt]

Yep, so it seems the Bremen data is the odd one out. Though the updated extent has moved more inline with the other two.

P.S.

OSI SAF service message #2112
Sent on Thu, 27/08/2020 - 11:27 UTC

Title : Corrupted product Global Sea Ice Concentration (AMSR2) OSI-408

Message :

Dear OSI SAF Sea Ice Concentration User,


Due to an anomaly in the processing chain the product with timestamp
"202008261200" for the Northern Hemisphere is corrupted and will be removed.
We are working on solving this issue. We apologize for any inconvenience.
Best regards,

OSI SAF Team

[Freegrass]

Latest Five Day Forecast + Last 24h
Wind @ Surface
Large GiF!

This new storm is gonna tear-off that entire corner north of Fram, isn't it?

I've added the last 24 hours to see the damage being done right now north of Nares.

Edit: There was a delay in the data, but it just came in, and so I changed the forecast with the latest data, which looks even worse for the ice.

[ArcticMelt2]

This new storm is gonna tear-off that entire corner north of Fram, isn't it?

This is bad. A German icebreaker recently reported that there is a lot of open water and weak ice. Where is the perennial thick ice that "Cryosat-2" saw this spring? The storm could wreak havoc on the ice in the area.

https://www.highnorthnews.com/en/international-mosaic-arctic-expedition-reaches-north-pole

The year-long MOSAiC international science expedition traveled across the geographic North Pole just after midday on August 19, which the crew celebrated with a small gathering on the Polarstern’s bridge. The Polarstern research icebreaker traveled along the Fram Strait on the North-east side of Greenland in a region that historically used to be home to thick multiyear ice. The vessel, however, encountered only light ice and completed the journey in just six days.

“Up until 87° 30’ North, for the most part we passed through open water, in some cases stretching to the horizon,” recalls MOSAiC Expedition Leader Prof Markus Rex from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research.

The researchers knew from satellite imagery that ice conditions would be light. However, they weren’t sure if this was simply due to wind and currents pushing the ice apart and were worried that the ice could compact again around them. “Then we would have been caught in a mousetrap, and we could have become trapped in the ice,” Rex explained.

Soft and easy
Those concerns, however, proved unwarranted as once the ship arrived in the region the scientists found that most of the ice had really melted away and wasn’t simply broken up by wind. The Polarstern’s captain, Thomas Wunderlich, confirmed the surprisingly easy ice conditions.

“I’m very surprised to see how soft and easy to traverse the ice up to 88° North is this year, having thawed to the point of being thin and porous. Normally it’s wise to avoid the region north of Greenland, because it’s home to the thicker and older ice, and virtually impassable. But now we’re finding extended stretches of open water, reaching nearly to the Pole.”

[Milwen]

HYCOM 7-day prediction - thicker ice moving to Beaufort again.

[UCMiami]

Born from the void - love you animations and the other static pictures you are creating. One suggestion that other animators have used - it might be nice to end with a comparison of the first image for a couple of seconds followed by the last image before it replays. It is nice to see the slow progression followed by the 'before/after'. Having never done any of this I am not sure how complicated this would be.

It almost looks like the Northern northwest passage - the straight shot from Baffin Bay through Viscount Melville and out the MClure could be open for a very nimble boat weaving through the remnants of ice.

The slow but steady losses in the Beaufort arm are what I watch - how long they can continue and what remains is the question.

[BornFromTheVoid]

Born from the void - love you animations and the other static pictures you are creating. One suggestion that other animators have used - it might be nice to end with a comparison of the first image for a couple of seconds followed by the last image before it replays. It is nice to see the slow progression followed by the 'before/after'. Having never done any of this I am not sure how complicated this would be.

That's no problem. Will add it on tomorrow (if I remember).

in the meantime, all previous 20 melt seasons now produce the 2nd lowest NSIDC extent minimum.

[Shared Humanity]

Latest Five Day Forecast
Wind + Temp @ Surface
Large GiF!

That persistent high is going to push some very fragile ice on the Pacific side into some rather warm Chukchi waters.

[Freegrass]

Latest Five Day Forecast
Wind + Temp @ Surface
Large GiF!

That persistent high is going to push some very fragile ice on the Pacific side into some rather warm Chukchi waters.

It looks like it. The ice edge there will get very dispersed, and then all we need is some decent waves to make it go poof...

[igs]

Yep, so it seems the Bremen data is the odd one out. Though the updated extent has moved more inline with the other two.

As I understand it, the difference is that the data from the University of Bremen have a much higher resolution.

The University of Bremen uses a resolution of 6.25 km, NSIDC 25 km.

About JAXA talk about 10 km.

https://svs.gsfc.nasa.gov/4684

Two JAXA datasets used in this animation are the 10-km daily sea ice concentration and the 10 km daily 89 GHz Brightness Temperature.

So the chances of breaking the 2012 record are growing.

Just thought something along this line too, we should not forget about the typical german nack for accuracy and then as you say, it's based on higher resulution and looking at area, it's very well possible the others will make up for the difference quite quickly over the next 5-10 days.

Either way I expect losses to pick up to about 2 times the daily loss than what they currently are,, means, between 50-90 km2.

Looking at the Beaufort appendix we are in for that and then for the north of greenland part and greenland see part I can't see what exctly will happen to the exported ice, especially not how fast it will melt, so that part could slow down over all losses for a few days to be compensated later in time.

[SimonF92]

This is the furthest south Fram export has been in 20 years of Worldview data for this week

(Actually its tied with 2007)

[ArcticMelt2]

https://twitter.com/AlaskaWx/status/1299022432297029633

Sea ice extent in the Beaufort Sea north of Alaska & NW Canada is now dropping quickly in @NSIDC  data. August 26th #seaice extent ranks as 12th lowest in the satellite era, and is lower than every year prior to 2007 except 1998.

[GoSouthYoungins]

Where is the perennial thick ice that "Cryosat-2" saw this spring?

It melted. I dunno if you saw the weather since the spring, but it was warm and sunny. That melts ice.

[UCMiami]

Igs - while 3 km vs 25 km (and other resolutions in between) would appear to be a no brainer in terms of accuracy, there is a catch and it is the same 'catch' that creates the argument about extent vs area measurements. The satellite sensors and the interpretation of them is fraught with inaccuracies - wet ice vs. dry ice, melt pond vs. open lead, cloud/fog vs. clear, etc. that these inaccuracy can actually be magnified the smaller the grid size and the more detailed (area vs extent) the analysis tries to get.

The daily UH false color arctic images are a perfect example as the deep purple flashes on and off in waves as presumable cloud banks move across the pack. Whatever causes it, it is clearly not underlying changes to the ice. The filters that most systems use to get rid of false readings of ice in the various peripheral seas during the summer is another example of the inherent problems with the current technology available (the St Lawrence has been ice free for months, but a filter is required to make sure it stays that way on data sets.)

[Freegrass]

Latest Five Day Forecast
Wind @ Surface + Total Precipitable Water
Large GiF!

That high is really trying hard to cool things down...

[ArcticMelt2]

Igs - while 3 km vs 25 km (and other resolutions in between) would appear to be a no brainer in terms of accuracy, there is a catch and it is the same 'catch' that creates the argument about extent vs area measurements. The satellite sensors and the interpretation of them is fraught with inaccuracies - wet ice vs. dry ice, melt pond vs. open lead, cloud/fog vs. clear, etc. that these inaccuracy can actually be magnified the smaller the grid size and the more detailed (area vs extent) the analysis tries to get.

The daily UH false color arctic images are a perfect example as the deep purple flashes on and off in waves as presumable cloud banks move across the pack. Whatever causes it, it is clearly not underlying changes to the ice. The filters that most systems use to get rid of false readings of ice in the various peripheral seas during the summer is another example of the inherent problems with the current technology available (the St Lawrence has been ice free for months, but a filter is required to make sure it stays that way on data sets.)

But in the case of the 2012's minimum, the University of Bremen has no significant differences with JAXA and NSIDC. In all three cases, the result is about 3.2 million square kilometers. Now there are actually many kilometer-long holes in the Beaufort Sea and other places, which make a difference of almost half a million km2. Check out optical images in Worldview.

From a neighboring topic:

JAXA ARCTIC SEA ICE EXTENT:  4,172,910 KM2 as at 26-Aug-2020
- Extent is  491 k MORE than 2012

NSIDC Total Area as at 26-Aug-2020 (5 day trailing average) 2,761,785 KM2 
- 2020 Area is 109 k more than 2012
- 2020 EXTENT is 451 k more than 2012       

[pearscot]

I'm surprised no one has mentioned it yet, but today's the first somewhat clear view above Greenland in quite some time. It looks like export towards the Fram Strait has been almost completely severed off from the narrow triangle that forms on the Greenland's east shore.

The entire region just looks real unstable and fragile. With the upcoming strong winds projected to rip what's left into the Atlantic I think there's still some area to lose here.

[ArcticMelt2]

https://twitter.com/ECCC_CIS/status/1299038988515397633

#Seaice cover in northern Canadian and Alaskan waters remains below normal this summer. 9th lowest #ice cover for this week of the melt season. #Arctic #Canada

[igs]

Igs - while 3 km vs 25 km (and other resolutions in between) would appear to be a no brainer in terms of accuracy, there is a catch and it is the same 'catch' that creates the argument about extent vs area measurements. The satellite sensors and the interpretation of them is fraught with inaccuracies - wet ice vs. dry ice, melt pond vs. open lead, cloud/fog vs. clear, etc. that these inaccuracy can actually be magnified the smaller the grid size and the more detailed (area vs extent) the analysis tries to get.

The daily UH false color arctic images are a perfect example as the deep purple flashes on and off in waves as presumable cloud banks move across the pack. Whatever causes it, it is clearly not underlying changes to the ice. The filters that most systems use to get rid of false readings of ice in the various peripheral seas during the summer is another example of the inherent problems with the current technology available (the St Lawrence has been ice free for months, but a filter is required to make sure it stays that way on data sets.)

Just to clarify, with accuracy I never meant or mean perfection or perfactly accurate, i was:

a) mentioning the general german way to do things more accurately in detail than many others

b) referring to a "HIGHER" accuracy in comparison to other models and platforms not meaning perfection in any way.

That said, all you're saying is perfectly correct, it's just not exactly what referring to what i said in context or in case of language barriers, meant to say.

Thanks for any clarification where my words could have been misunderstood by anyone.   

[Freegrass]

This is the furthest south Fram export has been in 20 years of Worldview data for this week

(Actually its tied with 2007)

I'm so glad you brought this up. I've been wanting to write a message about this for weeks now.

It seems like the ice in the CAA and the Greenland sea is melting out later than it used to in the past. And my question is if this has anything to do with a melting Siberian permafrost and the last remaining ice cube on Greenland...

In other words: A skewed polar cell that keeps the Americannot side cooler than should be expected in a normal melting Arctic.

[Cook]

It seems like the ice in the CAA and the Greenland sea is melting out later than it used to in the past. And my question is if this has anything to do with a melting Siberian permafrost and the last remaining ice cube on Greenland...

In other words: A skewed polar cell that keeps the Americannot side cooler than should be expected in a normal melting Arctic.

The Siberian permafrost is melting for the same reason that the sea ice is melting, a warmer atmosphere. I don't believe they are directly connected. A warm Siberia and cold Greenland are now normal and since Greenland still has it's ice cube it will warm slower than Siberia. Hence, the last of the ice will hang on for the longest in the area north of Greenland.

Some general comments on this thread.

1. Moderators are doing a fantastic job and showing the patience of saints.

2. Kindly cut the emotive language to a minimum. You may be in deep fear and horror of what is going on but discussing that here is not very helpful. (My personal fear is that the ice will stick around longer than expected, hence keeping the trans polar sea route closed rather than open which would be a great benefit to shipping and should reduce the amount of CO2 emitted by it. As far as I am concerned the sooner the ice melts be better, but this is just my point of view and harping on about it in this thread is out of place.)

3. Limit the numerical weather predictions shown/discussed to the first 3 days or so. Discussing what this or that model is doing farther out than that is academic and derailing in my opinion.

[binntho]

Hence, the last of the ice will hang on for the longest in the area north of Greenland.

I don't think the link between the Greenland glacier and the surrounding ice cover is that clear. As the current year has shown us, ice is not hanging particularly well on to the north coast of Greenland.

It sems to me that  the presence of the glacier creates conditions for strong downslope winds with a significant foehn factor that is increasingly able to clear ice away from the shore. And of course, the "last of the ice" will be pushed every which way by winds anyway and will not "hang on" anywhere.

[Frivolousz21]

Could be an early minimum.

With that anti cyclone dominating while we lose insolation

[Tigertown]

Could be an early minimum.

With that anti cyclone dominating while we lose insolation

That might just be, but I feel like we can have one more short run of a few hundred thousand. Either way, It will be real interesting to see where the volume settles at.

[Aluminium]

August 23-27.

2019.

[binntho]

August 23-27.

2019.

Thanks as always Aluminium for your great animations!

Looking at this one, it amazes me to see how quickly the Laptev front retreaets from the current winds. If it werent for some dispersion in Beufort and the Chukchi front, I think we would be seeing significantly bigger extent losses.

[Freegrass]

Latest Five Day Forecast
Wind + Temp @ Surface
Large GiF!

[BornFromTheVoid]

Here's today's images. Lots of concentration increases, with ice loss continuing on the Laptev and Kara side of the pack thanks to the winds.
And a bonus animation between the 23rd and 27th, with the change highlighted in last frame as requested!

[peterlvmeng]

The top melting is still strong between north pole and Laptev sea(East Siberian sea)(2020.08.28). The bottom melting is aggressive to melt those region (2020.08.26). The sea water temperature is still high and will not be dramatically cooled down. The surface air temperature is gradually dropping down and close to zero degree. I want to know how strong the bottom melt will be.

[ArcticMelt2]

Could be an early minimum.

It is unlikely, never any lows in August.

https://forum.arctic-sea-ice.net/index.php/topic,3183.0.html

NSIDC extent minimum

[Tor Bejnar]

For years there has been discussion of the "Laptev Bite".  Who would have thought there would ever be a "Greenland Bite"?

[gerontocrat]

I am definitely not a meteo man
However , despite the current vagaries of GFS, I am willing to guess that the a lot of warmth will be brought in from Central & Western Siberia into the Central Arctic Sea in the next few days.

I am also willing to guess that with peristent fairly strong winds the Atlantic Front will be pushed even closer to 85 North, and will include real melt from ocean and air. Will Central Arctic Sea extent and area be this year's real record breaker?

What happens as one looks further over towards the CAA ? Increased concentration? Garlic press?
And the Beaufort? Not a clue.

Effect on overall Arctic extent and area? Not a clue.

[Freegrass]

Latest Five Day Forecast
Wind @ Surface
Wind + Temp @ 850hPa
Wind @ 250hPa
Large GiFS!

[UCMiami]

BornFTV-
Very nice.
With the current winds there is a noticeable shift (subtle) of the whole pack toward the Beaufort with the exception of the Atlantic front above the Fram where it has at least stalled and may actually be trying to restart the export down the Fram. Will be interesting to see if any ice actually enters the Fram with the forecast calling for some strong winds against the NE edge of Greenland.

On an early question about the southern extent of ice in the Greenland Sea being exceptional at this date - isn't this mostly a result of the unusually high level of export in the Fram this year and the thicker quality of ice comprising most of that export. That ice in effect created a buffer for the ice along the Greenland coast delaying its exposure the the open seas. The fact that the ice north of Greenland is exceptionally weak this year belies theories that what has happened on the Asian side (land and sea) is being counterbalanced by unusual strength on the Greenland side.