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P-maker

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Re: The 2020 melting season
« Reply #4650 on: August 08, 2020, 08:06:20 PM »
Freegrass,

Thanks for posting these representative charts.

It's fascinating that during spring - early summer we had a near constant airflow from Bering to Brussels. This was a consistent advection of clean, cold air from the largest ocean on earth ( the Pacific ) to the largest continent ( Eurasia ).

Now, in the late summer - early autumn, we have the complete opposite general flow of air from Brussels to Bering. Nearly all the forecast models have had a tendency for some time to build up a high pressure bridge from northern Europe to the Pacific.

Since this seasonal change of winds have only manifested itself over the past couple of years, it may be too early to give it some kind of large scale monsoon name, but nonetheless, it is about time to figure out if this pattern of seasonal wind change has come to stay for a number of years or not.

Freegrass

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Re: The 2020 melting season
« Reply #4651 on: August 08, 2020, 08:41:26 PM »
Latest Five Day Forecast
Wind @ Surface + Total Precipitable Water
Wind + Temp @ 850hPa
Large GiFS!

I waited an extra hour and a half, but Nullschool still didn't update one file, hence the error at the end...
Now let's pray...

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ArcTickTock

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Re: The 2020 melting season
« Reply #4652 on: August 08, 2020, 09:05:20 PM »
Really I am not surprised at the slow down in extent losses as there was a lot of aggressive preconditioned sea ice this season and much of that melted out quickly and completely in July leaving no easy melt remaining.  Subsequently we have seen aggressive melt and disruption of the Beaufort and Chukchi and disturbing weakness north and east of Peary Land to a degree I cannot recall seeing in prior years.  Almost looks like a channel may form across the Fram and up and east of the Morris-Jesup Plateau towards the pole.  Additionally the situation looks to be un-favourable along the Atlantic front ( if no more melt occurs there it is already not a good year ) or the CAA.

Thus I am surprised by commentary anticipating a continued slowdown in extent losses when it looks much more like losses are about to pick up again.

Freegrass

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Re: The 2020 melting season
« Reply #4653 on: August 08, 2020, 09:06:38 PM »
Freegrass,

Thanks for posting these representative charts.
No problem P-maker. I'm happy I finally found a way to contribute to this forum and the climate debate in a useful way. I really appreciate the kind words.  :)

Too funny PMT!  ;D ;D ;D
But I'm still going down Nares in my canoe though...  ::)
Wondering why nobody is talking about the elephant in the room...

Needs a click.
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uniquorn

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Re: The 2020 melting season
« Reply #4654 on: August 08, 2020, 09:09:56 PM »
A clear(ish) day, so a picture for the record. https://go.nasa.gov/3gH0W8G nth greenland.

Freegrass

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Re: The 2020 melting season
« Reply #4655 on: August 08, 2020, 09:27:17 PM »
A clear(ish) day, so a picture for the record. https://go.nasa.gov/3gH0W8G nth greenland.
When I look at that, and then compare it to the DMI thickness map, I'm really starting to wonder if the DMI isn't a lot better than most people here thought. It's a perfect match in that area.
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I’M IN LOVE WITH A RAGER

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Re: The 2020 melting season
« Reply #4656 on: August 08, 2020, 09:28:27 PM »
Wow that weak spot almost reaches the pole! It looks like there's just rubble along the entire CAA/Greenland northern coastline at this point as well.

E: based on that DMI map, maybe it does reach the pole. I am very interested to see how that channel/region develops over the next few weeks as well as next season. Would be very interesting if this was the beginning of a new feature, similar to the mega crack over the last few years.

glennbuck

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Re: The 2020 melting season
« Reply #4657 on: August 08, 2020, 09:54:50 PM »
JAXA AMSR2 Arctic Sea ice average thickness, this was not available for the 4th of August and it looks like it set a new seasons record low beating 2015,s record low, that was set later in August.

7th August 2020, has dropped below the new record set on the 4th August 2020.
« Last Edit: August 08, 2020, 11:13:53 PM by glennbuck »

uniquorn

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Re: The 2020 melting season
« Reply #4658 on: August 08, 2020, 09:57:49 PM »
Again the actual poof event in a slightly higher resolution (I must admit that on the multicolored Bremen graph it looks even more devastating):
I understand why extent isn’t collapsing but I’m scratching my head trying to figure out why area isn’t dropping like a stone.  Makes no sense looking at Bremen and worldview.
Wipneus regional area, CAB, aug7

glennbuck

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Re: The 2020 melting season
« Reply #4659 on: August 08, 2020, 10:22:45 PM »

Wipneus regional area, CAB, aug7

Is this the same chart uniquorn? They both start around 4.400,000 km^2 but this one is lower, this is CAB from regional area NSIDC data, 7th August. Around 2,700,000 km^2 but yours is around 3,300,000 km^2.
« Last Edit: August 09, 2020, 10:24:47 PM by glennbuck »

igs

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Re: The 2020 melting season
« Reply #4660 on: August 08, 2020, 10:23:02 PM »
Really I am not surprised at the slow down in extent losses as there was a lot of aggressive preconditioned sea ice this season and much of that melted out quickly and completely in July leaving no easy melt remaining.  Subsequently we have seen aggressive melt and disruption of the Beaufort and Chukchi and disturbing weakness north and east of Peary Land to a degree I cannot recall seeing in prior years.  Almost looks like a channel may form across the Fram and up and east of the Morris-Jesup Plateau towards the pole.  Additionally the situation looks to be un-favourable along the Atlantic front ( if no more melt occurs there it is already not a good year ) or the CAA.

Thus I am surprised by commentary anticipating a continued slowdown in extent losses when it looks much more like losses are about to pick up again.

You're most probably on the wrong track and I am surprised that you cannot see what's visible with our naked eyes in addition to the many other parameters that were explained in detail.


We shall see century drops again and i recommend patience. Nature does not follow our "whishful" thinking paterns.

As I posted earler, as soon as a chart doesn't follow a linear curve to oblivion too many jump at each cliff and each slowdown as that would make up for the rest of the season.


I promise you that within 14 days you will have understood and changed your mind.

I personally opted all season for second place around 3.5M km2 extent and stick to it

BornFromTheVoid

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Re: The 2020 melting season
« Reply #4661 on: August 08, 2020, 10:54:59 PM »
When I look at that, and then compare it to the DMI thickness map, I'm really starting to wonder if the DMI isn't a lot better than most people here thought. It's a perfect match in that area.

Might find this of use.
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

Csnavywx

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Re: The 2020 melting season
« Reply #4662 on: August 08, 2020, 11:19:38 PM »
Comparisons to 2011 seeming increasingly valid. 2011 was a sneaky CAB volume destroyer. Though a BOE is still a little ways off, a crippling blow is starting to consistently only be one step away. Combo a low vol spring start with a summer like this one and viola. We came decently close in 2016. The pack was a wreck in Sep that year.

Neven

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Re: The 2020 melting season
« Reply #4663 on: August 08, 2020, 11:23:50 PM »
Really I am not surprised at the slow down in extent losses as there was a lot of aggressive preconditioned sea ice this season and much of that melted out quickly and completely in July leaving no easy melt remaining.  Subsequently we have seen aggressive melt and disruption of the Beaufort and Chukchi and disturbing weakness north and east of Peary Land to a degree I cannot recall seeing in prior years.  Almost looks like a channel may form across the Fram and up and east of the Morris-Jesup Plateau towards the pole.  Additionally the situation looks to be un-favourable along the Atlantic front ( if no more melt occurs there it is already not a good year ) or the CAA.

Thus I am surprised by commentary anticipating a continued slowdown in extent losses when it looks much more like losses are about to pick up again.

You're most probably on the wrong track and I am surprised that you cannot see what's visible with our naked eyes in addition to the many other parameters that were explained in detail.

Re-read the comment, all the way to the end. You are in agreement.
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uniquorn

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Re: The 2020 melting season
« Reply #4664 on: August 08, 2020, 11:35:39 PM »

oren

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Re: The 2020 melting season
« Reply #4665 on: August 08, 2020, 11:45:16 PM »
Both are from the same site by Wipneus and use the same regional demarcation map ("CT"), but one shows NSIDC area data and the other UH AMSR2 3.125km area data.

oren

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Re: The 2020 melting season
« Reply #4666 on: August 08, 2020, 11:53:31 PM »
NSIDC has much coarser resolution but is much more affected by wet ice surface and melt ponds, so during the melting season NSIDC extent > UH extent > UH area > NSIDC area.

oren

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Re: The 2020 melting season
« Reply #4667 on: August 09, 2020, 12:11:53 AM »
glennbuck, I did not say it is always the same constant difference. It depends on ice and weather conditions. A detailed look at both charts (which I recommend that ypu undertake) will reveal differences. For example NSIDC area data says 2016 was lower than 2012 at minimum, while UH says the opposite.
If you have more questions on this please continue in the questions thread.

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Re: The 2020 melting season
« Reply #4668 on: August 09, 2020, 12:15:31 AM »
That is not what he said.  They are different data products that vary in their ability to handle melt ponds and wet ice. 

You can’t bank on some absolute number such as saying “NSIDC area will always be around 600,000 km^2 below the UH AMSR2 3.125km area data.” 

That might be correct today, but it could be different next week. 

Unfortunately, we don’t have a great way to measure the ice. Every method has its limitations. The best we can do is watch and compare and do our best to look at each tool and try to understand what it is telling us.

EDIT: I was typing my response at the same time as Oren. Sorry for being redundant.

uniquorn

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Re: The 2020 melting season
« Reply #4669 on: August 09, 2020, 12:28:53 AM »
Since Friv is not providing band367 images at the moment here is a closer look at an area north of chukchi/beaufort today https://go.nasa.gov/3iocPAY
deep red from band 367 indicating bare ice/water (click for comparison)

HapHazard

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Re: The 2020 melting season
« Reply #4670 on: August 09, 2020, 02:30:32 AM »
I'd love to hear from A-team about now.

miki

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Re: The 2020 melting season
« Reply #4671 on: August 09, 2020, 02:31:55 AM »
I'd love to hear from A-team about now.

I was thinking the same.

igs

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Re: The 2020 melting season
« Reply #4672 on: August 09, 2020, 03:15:14 AM »
Re-read the comment, all the way to the end. You are in agreement.

yep you're right, my bad, sorry

ArcTickTock

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Re: The 2020 melting season
« Reply #4673 on: August 09, 2020, 05:48:03 AM »
Really I am not surprised at the slow down in extent losses as there was a lot of aggressive preconditioned sea ice this season and much of that melted out quickly and completely in July leaving no easy melt remaining.  Subsequently we have seen aggressive melt and disruption of the Beaufort and Chukchi and disturbing weakness north and east of Peary Land to a degree I cannot recall seeing in prior years.  Almost looks like a channel may form across the Fram and up and east of the Morris-Jesup Plateau towards the pole.  Additionally the situation looks to be un-favourable along the Atlantic front ( if no more melt occurs there it is already not a good year ) or the CAA.

Thus I am surprised by commentary anticipating a continued slowdown in extent losses when it looks much more like losses are about to pick up again.

You're most probably on the wrong track and I am surprised that you cannot see what's visible with our naked eyes in addition to the many other parameters that were explained in detail.


We shall see century drops again and i recommend patience. Nature does not follow our "whishful" thinking paterns.

IGS I think you interpreted my comment completely in reverse.  I was saying I expect losses to pick up and was surprised at commentary saying that it would not.

tzupancic

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Re: The 2020 melting season
« Reply #4674 on: August 09, 2020, 06:22:49 AM »
Arctic Sea Ice melt 2020.

I do not agree with the current implication that the recent reduction in arctic sea ice extent decline indicates that the melting of ice in the Arctic Ocean in 2020 is not exceptional. 

To the contrary it appears that the melt in 2020 is unique and unprecedented. I would suggest, rather, that the current ongoing melt is ‘transformational’.


ArcTickTock

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Re: The 2020 melting season
« Reply #4675 on: August 09, 2020, 07:03:25 AM »
Trying out my first image post.  Independence Fjord in northern Greenland looking very broken up.  The red is vegetation.

ArcTickTock

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Re: The 2020 melting season
« Reply #4676 on: August 09, 2020, 07:08:38 AM »
So any wonder at the Milne IS breaking up goes away after seeing this image!  Have seen lots of images of Antarctic ice shelves and they never look like this down south.  That is one very unhappy ice shelf, melt ponds, rifting, garbage really.  BTW, the Milne IS is the upper right corner.

Freegrass

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Re: The 2020 melting season
« Reply #4677 on: August 09, 2020, 07:39:27 AM »
Latest Five Day Forecast
Wind + Temp @ Surface
Large GiF!
Now let's pray...

If the science don't fit our beliefs, we pray to God and cuddle up in our own delusional fantasy where everything makes sense again...

ArcTickTock

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Re: The 2020 melting season
« Reply #4678 on: August 09, 2020, 07:47:51 AM »
There was some curiosity about the sea ice holding out near SZ.  Here is the middle of the ice pack just south and west of October Revolution Island.  This is supposed to be natural colour, interesting...

oren

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Re: The 2020 melting season
« Reply #4679 on: August 09, 2020, 09:25:42 AM »
The Sverdrup Channel between Axel Heiberg on the right and Ellef Ringness and Amund Ringness on the left, in the CAA/PGAS. A few days after initial breakup, some of the ice is quickly transported (check out the very large floe heading south), and a lot of the ice simply seems to disappear in situ. It seems this is what happens when the total accumulated melt reaches the typical thickness achieved during winter.
Top to bottom is around 350 km. Click to animate and enlarge.

Thawing Thunder

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Re: The 2020 melting season
« Reply #4680 on: August 09, 2020, 10:21:06 AM »
a Bremen graph that I do not see often and that they don’t seem to publish often

Reposted that graph because I think it didn't get the attention it deserves. How parallel these lines stay over decades! In an environment that recently mostly produces divergent graphs!!! I think this is very revealing and helpful to understand what's happening in the Arctic. With such a constant indicator it's easier to predict future events. Again, very interesting.
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Jim Hunt

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Re: The 2020 melting season
« Reply #4681 on: August 09, 2020, 11:56:09 AM »
Quote
Fresh this morning from Terra, a rather cloudy view of the devastation near 80N, 150W:

https://GreatWhiteCon.info/2020/08/facts-about-the-arctic-in-august-2020/#Aug-09
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

BornFromTheVoid

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Re: The 2020 melting season
« Reply #4682 on: August 09, 2020, 12:00:04 PM »
Concentration changes between the 7th and 8th, using University of Bremen data
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

Freegrass

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Re: The 2020 melting season
« Reply #4683 on: August 09, 2020, 01:14:47 PM »
Latest Five Day Forecast
Wind @ Surface
Large GiF!
Now let's pray...

If the science don't fit our beliefs, we pray to God and cuddle up in our own delusional fantasy where everything makes sense again...

wdmn

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Re: The 2020 melting season
« Reply #4684 on: August 09, 2020, 01:43:31 PM »
There was some curiosity about the sea ice holding out near SZ.  Here is the middle of the ice pack just south and west of October Revolution Island.  This is supposed to be natural colour, interesting...

Something similar off the coast of Baffin Island. Likely an indication that this ice is the remnants of ridging in the shallow water up against the shore. Lots of sand gets pulled up into/splashed onto the ice during the freezing season.

EDIT: Adding another photo, this one from James Bay earlier in the season (July 13).
« Last Edit: August 09, 2020, 02:54:34 PM by wdmn »

Milwen

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Re: The 2020 melting season
« Reply #4685 on: August 09, 2020, 05:27:59 PM »
Nares export is accelerating. I followed some bigger ice floes there and most of them traveled almost 100km since yesterday. According to Nullschool wind speed forecast, there will be sustained export of ice from Greenland Sea to Laptev for next 3-4 days.

glennbuck

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Re: The 2020 melting season
« Reply #4686 on: August 09, 2020, 05:43:29 PM »
Sea Surface Temperature Anomaly, green circle near Svalbard, 5 C anomaly.

Sea Surface Temperature Anomaly in parts of the Kera Sea 13 C and the Laptev Sea 8 C.

Looking at the Sea Surface Temperatures, around -1.8 C in the middle of the CAB, 8 C near Svalbard and parts of Laptev Sea, Kera Sea 14 C.   Arctic Ocean -1.8 C  to +7 C.

Arctic Ocean near Svalbard, 7 C in green circle marked. 6 C above normal temp.

« Last Edit: August 11, 2020, 12:53:17 PM by glennbuck »

Freegrass

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Re: The 2020 melting season
« Reply #4687 on: August 09, 2020, 07:32:48 PM »
Latest Five Day Forecast
Wind @ Surface + Total Precipitable Water
Large GiF!
Now let's pray...

If the science don't fit our beliefs, we pray to God and cuddle up in our own delusional fantasy where everything makes sense again...

igs

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Re: The 2020 melting season
« Reply #4688 on: August 09, 2020, 07:48:51 PM »
Latest Five Day Forecast
Wind @ Surface + Total Precipitable Water
Large GiF!

Something tells me that we are heading towards multiple century drops with at least one or two multi-century drops.

At least I would have to revise all i learned over years thoroughly if that won't be the case over the next 2-10 days.

I see dire times for the ice ahead, waiting for FRIV and others to find the best words ;)
« Last Edit: August 09, 2020, 08:31:21 PM by igs »

glennbuck

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Re: The 2020 melting season
« Reply #4689 on: August 09, 2020, 08:00:51 PM »

Something tells me that we are heading towards multiple century drops with at least one or two multi-century drops.

At least I would have to revise all i learned over years thoroughly if that won't be the case over the next 2-10 days.

I see dire times for the ice ahead, waiting for FRIV to find the best words ;)

NSIDC daily extent

115,000 km^2 drop today

2020-08-08  5.645  −115

More to come probably.

Pmt111500

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Re: The 2020 melting season
« Reply #4690 on: August 09, 2020, 08:07:41 PM »
Yea, the drop from 20 cm (8inch.) to 0 inch ice may happen pretty much overnight. The buoys had some info on this.

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Re: The 2020 melting season
« Reply #4691 on: August 09, 2020, 08:19:43 PM »
Yea, the drop from 20 cm (8inch.) to 0 inch ice may happen pretty much overnight. The buoys had some info on this.
The serious speed up happens when the flows greater than 100m in size loose structural cohesion and break up.

At that point, lateral melt becomes a major source of loss and additional structural weakness leading to further fracturing.

In short cascading failure which is almost fractal in nature and devastating to the ice.
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Re: The 2020 melting season
« Reply #4692 on: August 09, 2020, 08:26:18 PM »
Seeing a century break in extent, I went to EOSDIS for a peek.

In the first attached image below is a cut-out of the larger link I have at the end of this post.

It's pretty much the Pacific half of the Arctic at 5K resolution, using the VIIRSS SNPP M11-I2-I1 filter.

(Edit: It's there primarily to give you a reference region, as a higher resolution attachment would be unpleasantly large.)

The second is from the Laptev earlier this year, (July 28th), and what most of the ice in the first image will likely look like in a week to 10 days, outside of the bastion in the lower right hand corner.  This is based on my observation of what the Laptev ice looked like on the 20th or there abouts.

Keep also in mind, unlike the 2013/14 ice which was in a not incomparable state, most of this ice is *south* of 80N, and will still be getting over 200w/m2 of insolation for the best part of August.

Worldview link for reference.

https://worldview.earthdata.nasa.gov/?v=-3067821.6709848186,-693739.4210033698,864338.3290151814,1548820.5789966302&p=arctic&t=2020-08-08-T18%3A03%3A57Z&l=Reference_Labels(hidden),Reference_Features(hidden),Coastlines,MODIS_Terra_CorrectedReflectance_Bands721(hidden),MODIS_Terra_CorrectedReflectance_Bands367(hidden),VIIRS_SNPP_CorrectedReflectance_BandsM3-I3-M11(hidden),VIIRS_SNPP_CorrectedReflectance_BandsM11-I2-I1,VIIRS_NOAA20_CorrectedReflectance_BandsM3-I3-M11(hidden),VIIRS_NOAA20_CorrectedReflectance_BandsM11-I2-I1(hidden),MODIS_Aqua_CorrectedReflectance_Bands721(hidden),VIIRS_NOAA20_CorrectedReflectance_TrueColor(hidden),VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor
« Last Edit: August 09, 2020, 08:38:28 PM by jdallen »
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Steven

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Re: The 2020 melting season
« Reply #4693 on: August 09, 2020, 08:29:09 PM »
The image below shows the 5-day median (pixel-wise) of the latest Bremen images.  I think this kind of smoothing helps to reduce cloud interference and other artefacts in the daily Bremen images.   (Another member of this forum, petm, used to post similar images frequently last year, but I haven't seen him on the forum recently.)




And here is the 3-day (rather than 5-day) median:
https://i.imgur.com/ApeHxsu.png

A-Team

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Re: The 2020 melting season
« Reply #4694 on: August 09, 2020, 09:33:10 PM »
This remarkable freeze/melt cycle has been unfortunate but perhaps inevitable, putting us literally in uncharted waters with regards to massive climate change impacts.

It’s easy to forget, as the post-BOE forum properly notes, that once upon a time the Barents, Baltic, Bering, Baffin. Chukchi, and Kara hosted millions of sq km of year-round ice. (And that not so long ago, 1000 m thick ice gouged the Lomonosov ridgetop.) On 08 Aug 2020, 38% of the remaining ice (the Arctic Ocean basin, was open water. Vast areas of tundra are free of reflecting snow as well. We’re already well into BOE in most respects.

What’s going on at the moment is baffling, notably between Greenland and the north pole. It’s clear we don’t really understand the current physical state of the ice. Thus even if surface weather were predictable three days out, where things will end up by mid-October still remains up in the air.

However we do have a good grip on some of the pre-conditioning events that have brought the ice to its current state:

-1- The melt season really began in the previous freeze season, even earlier. Vast areas of surprisingly thin 0.3m ice remained in the Laptev when the Polarstern moored on Oct 4th. That and a slow start to freeze-up are documented by thousands of km of ship thickness transects with no graduating SYI floes thick enough to stand on for Mosaic. (T Krumpen http://dx.doi.org/10.5194/tc-14-2173-2020)

-2- The TransPolar Drift over winter, as accurately imaged in Ascat time series, bore little resemblance to recent years in two key respects: months of very rapid Fram-ward displacement and extensional engagement of ice to the pole and beyond. Often the ice drift is just circumpolar.

-3- The whole icepack does not rotate CW with the TPD but rather participation is demarcated by immense  curvilinear leads, newly visualized in a dockside posting by L Kaleschke and enhanced on the Mosaic forum by directional convolution. These fracture lines, coincidentally or causally, approximately delimit the puzzling openings to the pole above Morris Jesup. A lot of MYI ice between Greenland and the pole was fractured by lead formation.

-4- Missing this year was any significant CW rotational movement of thick ice out of the western CAB. While this ice has never moved further than a half gyre in the last ten years of tracking, commonly a strip of CAB ice moves to inevitable melt in the warmer open seas of the Chukchi (which might be called internal export).

-5- Export out the Fram was robust during the TPD, pushing everything ahead of a 500 km east-west line through the initial position of the PS to oblivion in the Greenland Sea. Behind this line, newly formed Laptev ice filled the growing open water gap to shore. However, since mid-May, export out the Fram, SV-FJL gap, Bering Strait, CAA garlic press and Nares have all been inconsequential (and will remain so, too little time is left).

-6- A record heat wave off Ellesmere in mid July coupled with persistent easterly winds melted vulnerable matrix ice joining floes, enabling churning of offshore ice into residual rubble. The observed movement to the west is not unusual but it was far more narrowly restricted to the CAA coast in past events. The main CAB ice pack, being no longer attached to coastal land or ocean bottom, might be set adrift to elsewhere by persistent winds from the south. We’ve not yet seen that game-changer.

-7- The Pacific-side cyclone centered on July 27th hit like a tornado at 75º/-160º decimating the ice, on Sentinel-1 and WorldView, making clear that error-prone thickness and area/extent whole-ocean numbers don’t capture key issues such as ice mechanical strength, internal pressure or response to stress.

Both the Chukchi and slow-melting Beaufort were pre-conditioned by dispersion for flash lateral and bottom melt after the storm; note insolation today at 75º surprisingly is still 64% the strength the week centered on solstice (4th image below) but has to get through clouds and escape low angle surface reflection.

Are these independent events or somehow consequent to a single master change (such as breakdown trend of equatorial heat gradient as manifested in the jet stream)? Yes to a certain extent but this view has to be distinguished from the slot machine model put forward by Csnavywx in #4662.

That is, the multi-decadal downward trend of ice has created a set-up for which a coincidental confluence of bad weather events over a single freeze/melt cycle sequentially sum to an ice disaster. Even bland weather from here to October may suffice for a seriously below-trend outcome. Regardless of how the season turns out, as @Zlabe notes, fractional BOE has gone on all summer.

The files below expand or animate with a click. File names explain the topic addressed. I thank uniquorn for valuable discussions. Clouds are removed by setting a sequential five day AMR2 stack to 'darken only' in gimp.
« Last Edit: August 11, 2020, 02:03:02 PM by A-Team »

Freegrass

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Re: The 2020 melting season
« Reply #4695 on: August 09, 2020, 10:27:43 PM »
Welcome back A-team. Nice to finally meet you. That was an impressive post where this part stood out to me.

Quote
The main CAB ice pack, being no longer attached to coastal land or ocean bottom, might be set adrift to elsewhere by persistent winds from the south. We’ve not yet seen that game-changer.

I have always wondered if that could actually happen. If it ever did happen, that would definitely be a game changer.

Thank you for this enlightening piece of work!
Now let's pray...

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Niall Dollard

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Re: The 2020 melting season
« Reply #4696 on: August 09, 2020, 10:27:54 PM »
Thanks Neven  & A-team. Those techniques to "smooth" the Bremen images are working out very well and I think compare very well with the vis sat images.

For some reason I thought this year the Bremen images were more plagued with cloud and/or other artefacts.

uniquorn

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Re: The 2020 melting season
« Reply #4697 on: August 09, 2020, 10:48:16 PM »
Would normally post this on the megacrack thread but after A-Teams post it seems appropriate here. Worldview aqua modis of CAA/nthGreenland today https://go.nasa.gov/3fDFsIl
click for full resolution
Still some signs of rotation north of Lincoln Sea

oren

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Re: The 2020 melting season
« Reply #4698 on: August 09, 2020, 11:52:28 PM »
Good to read your analysis A-Team. Sharp and to the point as usual.
It's easy to forget, after the crazy summer we had, how the Fram-ward flow was on steroids this winter.

jdallen

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Re: The 2020 melting season
« Reply #4699 on: August 09, 2020, 11:57:50 PM »
This remarkable freeze/melt cycle has been unfortunate but perhaps inevitable, putting us literally in uncharted waters with regards to massive climate change impacts.
This may be the intro to the Arctic pack's, if not our current civilization's epitaph.
This space for Rent.