Support the Arctic Sea Ice Forum and Blog

Author Topic: Latest PIOMAS Volume update  (Read 1896933 times)

gerontocrat

  • Multi-year ice
  • Posts: 20378
    • View Profile
  • Liked: 5289
  • Likes Given: 69
Re: Latest PIOMAS update (May 2020)
« Reply #3250 on: May 06, 2020, 01:30:41 PM »
PIOMAS Volume as at 1 May 2020**   22,522 km3

And a look at sea ice volume, thickness & area, contrasting the seven seas of the High Arctic with the seven Peripheral Seas.
High Arctic
In April High Arctic sea ice volume barely changed at all, while sea ice area did decline quite sharply from mid-April. The result? Sea Ice thickness increased in April and may well continue to do so until mid-May.
"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)

gerontocrat

  • Multi-year ice
  • Posts: 20378
    • View Profile
  • Liked: 5289
  • Likes Given: 69
Re: Latest PIOMAS update (May 2020)
« Reply #3251 on: May 06, 2020, 01:45:23 PM »
PIOMAS Volume as at 1 May 2020**   22,522 km3 - Continued...

And a look at sea ice volume, thickness & area, contrasting the seven seas of the High Arctic with the seven Peripheral Seas.
Peripheral Arctic Seas
In April Peripheral Arctic sea ice volume declines sharply in Mid-March to early April, flat-lined to  mid-April & then declined sharply again from mid-April.
Sea Ice area of the Peripheral Seas has declined sharply continuously since early March, and at a faster rate than volume decline.

The result? Sea Ice thickness of the remaining ice has increased sharply since early March & is now 2nd highest in this century, having been in the top 3 since mid-March. Less ice but  thicker. What this means for future seq ice loss I really do not know.

Certainly the High Arctic & the Peripheral Seas are two very different beasties.
.
"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)

The Walrus

  • Young ice
  • Posts: 2827
    • View Profile
  • Liked: 149
  • Likes Given: 484
Re: Latest PIOMAS update (May 2020)
« Reply #3252 on: May 06, 2020, 01:56:45 PM »
Am I reading that correctly?  The ice in the peripheral seas is at the thickest it as been since the turn of the century?  Anyone have any insight into this?

gerontocrat

  • Multi-year ice
  • Posts: 20378
    • View Profile
  • Liked: 5289
  • Likes Given: 69
Re: Latest PIOMAS update (May 2020)
« Reply #3253 on: May 06, 2020, 02:44:07 PM »
Am I reading that correctly?  The ice in the peripheral seas is at the thickest it as been since the turn of the century?  Anyone have any insight into this?
Except for 2003 - but 2020 #1 from 22nd March to 14th April, and 2nd or 3rd since then. This year it is due to ssharp area loss (as it was in 2019).
"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)

oren

  • Moderator
  • First-year ice
  • Posts: 9805
    • View Profile
  • Liked: 3584
  • Likes Given: 3922
Re: Latest PIOMAS update (May 2020)
« Reply #3254 on: May 07, 2020, 05:50:26 AM »
Am I reading that correctly?  The ice in the peripheral seas is at the thickest it as been since the turn of the century?  Anyone have any insight into this?
PIOMAS thickness sometimes does funny things. The lower the ice area, often the higher the thickness. This is either an artifact of the model, or a result of the natural distribution of thicknesses in the Arctic ocean. What is the true answer? Hard to know without direct knowledge of the actual ice thickness distribution.
Example: If you have a peripheral sea concentration of 0.2m (30% - newly frozen FYI), 0.5m(30% - peripheral FYI), 1.5m(30% - good FYI or MYI exported from northern waters) and 3m(10% - pressure ridges) ice, average thickness is 0.37m. Now reduce all thicknesses by 0.2m due to melting. Your new concentration is 0.3m(30%), 1.3m(30%) and 2.8m(10%), total of 70%. Average thickness is 0.46m. Cause for celebration? Not quite. Any relation between my distribution and actual reality? None that I am aware of.

oren

  • Moderator
  • First-year ice
  • Posts: 9805
    • View Profile
  • Liked: 3584
  • Likes Given: 3922
Re: Latest PIOMAS update (May 2020)
« Reply #3255 on: May 07, 2020, 06:41:32 AM »
It's a tale of two Arctics. The CAB and Beaufort, as also shown in the diff map posted by Wipneus, are sporting positive anomalies (compared to other low years), while the Siberian side is tracking at lowest levels for the date. In principle, this could bring about an early drop in the Laptev and ESS, while stalling in the CAB and ending the season with high area/extent. Or the CAB could be hit by strong export, while the adjacent seas are decimated. Or early open water in the Inner Basin could cause low albedo and extra energy in the system. Or it could make no difference at all. Stay tuned...

FishOutofWater

  • Nilas ice
  • Posts: 1088
    • View Profile
  • Liked: 696
  • Likes Given: 332
Re: Latest PIOMAS update (May 2020)
« Reply #3256 on: May 07, 2020, 09:07:15 PM »
The somewhat surprising ice thickness and volume distribution in the Arctic seas and high Arctic is the result of the very strong polar vortex this winter which maintained strong cyclonic winds over the polar region. Despite the strong polar vortex, which kept cold air pretty well bottled up through the NH winter, polar region temperatures averaged above normal. That's solid evidence of Arctic warming. It should have been colder than normal with this winter's Arctic oscillation pattern.

The normal summer weather pattern is for Fram ice export to decline so, although an increased percentage of thicker ice is in position for export, don't expect massive export. As has been the case for the past decade, the ice extent in September will be controlled primarily by the weather. Nothing looks exceptional to me at this time except for global oceanic heat content which is at a record high. That heat is taking take its toll on the ice over the decades, but there's no sign yet in the weather & climate models of anything exceptional this summer.

blumenkraft

  • Guest
Re: Latest PIOMAS update (May 2020)
« Reply #3257 on: May 07, 2020, 09:08:33 PM »
Welcome back FOOW! Glad to see you around. :)

Jim Hunt

  • First-year ice
  • Posts: 6268
  • Don't Vote NatC or PopCon, Save Lives!
    • View Profile
    • The Arctic sea ice Great White Con
  • Liked: 893
  • Likes Given: 87
Re: Latest PIOMAS update (May 2020)
« Reply #3258 on: May 08, 2020, 11:46:31 AM »
The ice in the peripheral seas is at the thickest it as been since the turn of the century?  Anyone have any insight into this?

Perhaps?

http://GreatWhiteCon.info/2020/01/wheres-the-thickest-arctic-sea-ice-gone/
"The most revolutionary thing one can do always is to proclaim loudly what is happening" - Rosa Luxemburg

gerontocrat

  • Multi-year ice
  • Posts: 20378
    • View Profile
  • Liked: 5289
  • Likes Given: 69
Re: Latest PIOMAS update (May 2020)
« Reply #3259 on: May 08, 2020, 01:17:47 PM »
The ice in the peripheral seas is at the thickest it as been since the turn of the century?  Anyone have any insight into this?

Perhaps?

http://GreatWhiteCon.info/2020/01/wheres-the-thickest-arctic-sea-ice-gone/
When the melting season starts, thin ice at the edges quickly melts - large area loss and small volume loss. So average thickness of the remaining ice goes up.

This winter saw a (relatively) high maximum - so even more thin ice to quickly melt & increase average thickness of the remaining ice even more?
"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)

grixm

  • Grease ice
  • Posts: 699
    • View Profile
  • Liked: 374
  • Likes Given: 131
Re: Latest PIOMAS update (May 2020)
« Reply #3260 on: May 26, 2020, 10:05:29 PM »
Was there an update for mid-May?

Wipneus

  • Citizen scientist
  • Young ice
  • Posts: 4220
    • View Profile
    • Arctische Pinguin
  • Liked: 1025
  • Likes Given: 0
Re: Latest PIOMAS update (May 2020)
« Reply #3261 on: May 27, 2020, 12:09:54 PM »
Was there an update for mid-May?

No, and by this time not likely will there be one.

Wipneus

  • Citizen scientist
  • Young ice
  • Posts: 4220
    • View Profile
    • Arctische Pinguin
  • Liked: 1025
  • Likes Given: 0
Re: Latest PIOMAS update (June 2020)
« Reply #3262 on: June 03, 2020, 10:28:16 AM »
PIOMAS gridded thickness data has updated to day 152 (~1 June). Calculated volume was 19.6 [1000 km3], 6th lowest on that day of year.

Here is the May animation.

Wipneus

  • Citizen scientist
  • Young ice
  • Posts: 4220
    • View Profile
    • Arctische Pinguin
  • Liked: 1025
  • Likes Given: 0
Re: Latest PIOMAS update (June 2020)
« Reply #3263 on: June 03, 2020, 10:47:47 AM »
The volume and volume-anomaly graphs. Click to size.

Wipneus

  • Citizen scientist
  • Young ice
  • Posts: 4220
    • View Profile
    • Arctische Pinguin
  • Liked: 1025
  • Likes Given: 0
Re: Latest PIOMAS update (June 2020)
« Reply #3264 on: June 03, 2020, 11:03:12 AM »
A large amount of ice crossed the imaginary line in the Fram Straight in the beginning of May.

Wipneus

  • Citizen scientist
  • Young ice
  • Posts: 4220
    • View Profile
    • Arctische Pinguin
  • Liked: 1025
  • Likes Given: 0

Wipneus

  • Citizen scientist
  • Young ice
  • Posts: 4220
    • View Profile
    • Arctische Pinguin
  • Liked: 1025
  • Likes Given: 0
Re: Latest PIOMAS update (June 2020)
« Reply #3266 on: June 03, 2020, 11:10:57 AM »
Thickness map for day 152, compared with previous yeas and their diff's. Click for size.

RikW

  • Frazil ice
  • Posts: 244
    • View Profile
  • Liked: 44
  • Likes Given: 19
Re: Latest PIOMAS update (June 2020)
« Reply #3267 on: June 03, 2020, 01:21:09 PM »
What a difference between 2020 and other years in the beaufort sea. Same with area and extent for beaufort sea.

Curious why that is the case, can it be the fresh water lens, thus higher melting point?

gerontocrat

  • Multi-year ice
  • Posts: 20378
    • View Profile
  • Liked: 5289
  • Likes Given: 69
Re: Latest PIOMAS update (June 2020)
« Reply #3268 on: June 03, 2020, 02:51:06 PM »
I attach volume graphs & tables formatted as for the Jaxa extent data. No drama; 6th lowest volume at the beginning of May, ditto at the end of the month.
« Last Edit: June 03, 2020, 03:24:26 PM by gerontocrat »
"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)

gerontocrat

  • Multi-year ice
  • Posts: 20378
    • View Profile
  • Liked: 5289
  • Likes Given: 69
Re: Latest PIOMAS update (June 2020)
« Reply #3269 on: June 03, 2020, 09:51:18 PM »
The May monthly average for 2020 is 596 km3 above the linear trend (somewhat more than 2 years of the annual linear trend loss of 286 km3.

This above trend volume is most noticeable in the peripheral seas.
"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)

oren

  • Moderator
  • First-year ice
  • Posts: 9805
    • View Profile
  • Liked: 3584
  • Likes Given: 3922
Re: Latest PIOMAS update (June 2020)
« Reply #3270 on: June 04, 2020, 05:35:38 AM »
Interesting volume developments around the Arctic. The ESS continues to set new records, while the Beaufort and CAA appear to be laggards this year, increasing the chances of a higher volume finish in these regions, though this is still far from certain. And will the CAB follow 2014 to join the "high volume" years, or will it make a dive for the "low volume" years? My bet is on the latter, but the Arctic is always full of surprises.
My personal take on these volume anomalies has to do with sharply reduced ice movement out of the Beaufort which also affects the (normally importing) ESS, and a slowdown of export from the CAB to Fram/Barents, preserving the vulnerable positive anomaly near Svalbard.

Phoenix

  • Guest
Re: Latest PIOMAS update (June 2020)
« Reply #3271 on: June 04, 2020, 10:27:58 AM »
Thank you Wip, Gero and Oren for the wonderful volume data and graphics.

As I look at the information and try to explore what it means for projecting the minimum, I am drawn to a feature of the CAB chart where the vast majority of the ice is  going to be at the minimum.

The chart indicates very little annual variation in CAB volume loss from days 165 to 210 with an exception for 2017 in days 165 to 180. (Edit: 2014 is also an exception with low CAB loss during peak season). This period of low variation coincides with a period of low temperature variation as shown in 60+ years of DMI 80N temperatures.

It suggests that the primary opportunity for a year to differentiate itself in CAB volume loss performance is limited and needs to come before or after this 45 day window. With the early season window approaching a close and limited current momentum, it seems the possibilities for 2020 to break new ground is dependent on performance after Aug 1.
« Last Edit: June 04, 2020, 02:44:01 PM by Phoenix »

oren

  • Moderator
  • First-year ice
  • Posts: 9805
    • View Profile
  • Liked: 3584
  • Likes Given: 3922
Re: Latest PIOMAS update (June 2020)
« Reply #3272 on: June 04, 2020, 03:20:31 PM »
Here's another one for you Phoenix

Phoenix

  • Guest
Re: Latest PIOMAS update (June 2020)
« Reply #3273 on: June 04, 2020, 03:47:20 PM »
Here's another one for you Phoenix

Thanks Oren. It would be interesting to understand the volume breakdown by sea at the minimum. Something parallel to Gerontocrat's area data. My gut tells me that CAB ice is generally thicker at the minimum so the 3D percentage in the CAB is even higher than the 2D % in the CAB, which is already quite high.

Perhaps I can deduce this information from looking at old graphs.

I think the CAB volume is leaps and bounds above the rest in importance, but the most refined understanding of course involves understanding the rest. I don't see a chart for Greenland Sea for example and am curious about that.

One thing that I can assure all three of you is that if you put the data out there, there is at least one customer who will study it !!

Aluminium

  • Nilas ice
  • Posts: 1463
    • View Profile
  • Liked: 1140
  • Likes Given: 680
Re: Latest PIOMAS update (June 2020)
« Reply #3274 on: June 06, 2020, 10:46:04 PM »
Regional ice volume. Experimental chart 1.

icefisher

  • New ice
  • Posts: 60
    • View Profile
  • Liked: 6
  • Likes Given: 0
Re: Latest PIOMAS update (June 2020)
« Reply #3275 on: June 06, 2020, 11:04:28 PM »
Great bubble chart Aluminium.  Clear, simple and easy to understand.  Used extensively in business apps. 

Phoenix

  • Guest
Re: Latest PIOMAS update (June 2020)
« Reply #3276 on: June 07, 2020, 02:45:30 AM »
Regional ice volume. Experimental chart 1.

Love innovation. Looks like the solar system with a sun and 9 planets. Run an example for yourself with data at the minimum and 90% of the ice in the CAB. The circles for some of the regions would be too small to see.

The image is useful in demonstrating the dominance of the CAB.

Personally, I would be quite happy with something like gerontocrat's area spreadsheets that are shown in the data thread. Date rows with columns for the seas. If one groups all of the seas which we know will be going to ~ zero at the minimum, it becomes a very small spreadsheet. Something as simple as two columns is useful. One for CAB, one for the rest.
« Last Edit: June 07, 2020, 11:02:49 AM by Phoenix »

grixm

  • Grease ice
  • Posts: 699
    • View Profile
  • Liked: 374
  • Likes Given: 131
Re: Latest PIOMAS update (June 2020)
« Reply #3277 on: June 07, 2020, 07:24:07 AM »
Regional ice volume. Experimental chart 1.

I don't get it, what does the axes and dot sizes mean?

oren

  • Moderator
  • First-year ice
  • Posts: 9805
    • View Profile
  • Liked: 3584
  • Likes Given: 3922
Re: Latest PIOMAS update (June 2020)
« Reply #3278 on: June 07, 2020, 08:00:25 AM »
If I read this correctly, circle size is volume, Y axis is latitude, X axis is longitude.
Nice chart!

psymmo7

  • New ice
  • Posts: 81
    • View Profile
  • Liked: 35
  • Likes Given: 17
Re: Latest PIOMAS update (June 2020)
« Reply #3279 on: June 07, 2020, 10:42:34 AM »
Hi Aluminium,
the bubble chart is a great idea.
It makes it much easier to conceptualise the relative contributions.
Could you please let us have updated versions - let's say weekly.

Aluminium

  • Nilas ice
  • Posts: 1463
    • View Profile
  • Liked: 1140
  • Likes Given: 680
Re: Latest PIOMAS update (June 2020)
« Reply #3280 on: June 07, 2020, 08:15:14 PM »
It would be interesting but, I guess, I will not have weekly updated data.

Experimental chart 2. Is it egg or nut?

oren

  • Moderator
  • First-year ice
  • Posts: 9805
    • View Profile
  • Liked: 3584
  • Likes Given: 3922
Re: Latest PIOMAS update (June 2020)
« Reply #3281 on: June 07, 2020, 08:29:57 PM »
Actually this one is even better.

oren

  • Moderator
  • First-year ice
  • Posts: 9805
    • View Profile
  • Liked: 3584
  • Likes Given: 3922
Re: Latest PIOMAS update (June 2020)
« Reply #3282 on: June 07, 2020, 08:32:21 PM »
Here is another volume chart, in which 2020 is currently at record low. High Arctic seas, excluding the CAB and the CAA. Some of the extra CAB volume is balanced by missing volume in adjacent seas. What does it mean? I am not sure but at the end of the season we will learn some more.

Juan C. García

  • Young ice
  • Posts: 3359
    • View Profile
  • Liked: 1279
  • Likes Given: 1127
Re: Latest PIOMAS update (June 2020)
« Reply #3283 on: June 07, 2020, 08:42:39 PM »
Actually this one is even better.
It is great!
Here is another volume chart, in which 2020 is currently at record low. High Arctic seas, excluding the CAB and the CAA. Some of the extra CAB volume is balanced by missing volume in adjacent seas. What does it mean? I am not sure but at the end of the season we will learn some more.
Also great!

If 2020 continues to lead the lowest on the peripherical High Arctic seas, I think that it will have some influence on September CAB and CAA volume.
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.

Aluminium

  • Nilas ice
  • Posts: 1463
    • View Profile
  • Liked: 1140
  • Likes Given: 680
Re: Latest PIOMAS update (June 2020)
« Reply #3284 on: June 07, 2020, 08:58:34 PM »
Another one. This is a forecast for June 30 based on the melting rate in 2019. June 30 is blue, May 31 is red.

blumenkraft

  • Guest
Re: Latest PIOMAS update (June 2020)
« Reply #3285 on: June 07, 2020, 09:03:36 PM »
IMHO the first version was better. This is a great visualization and it screams to be animated. ;)

Glen Koehler

  • Grease ice
  • Posts: 931
    • View Profile
  • Liked: 738
  • Likes Given: 1413
Re: Latest PIOMAS update (June 2020)
« Reply #3286 on: June 07, 2020, 10:12:21 PM »
Another one. This is a forecast for June 30 based on the melting rate in 2019. June 30 is blue, May 31 is red.
    Both versions are great.  I like the second that shows May 31 vs June 30 best.  Also agree that animation would be a nice addition (and more work no doubt!).  Whether comparative or not, animated or not, having some form of these bubble graphs at monthly intervals (or at mid-month if there is a PIOMAS update) would be an informative benchmark for tracking seasonal progression.  Thanks for introducing these.

    Maybe 5 or 10-year average melt rate instead of 2019?

    WOW - both Kara and Laptev GONE by June 30!
“What is at stake.... Everything, I would say." ~ Julienne Stroeve

Freegrass

  • Young ice
  • Posts: 3825
  • Autodidacticism is a complicated word...
    • View Profile
  • Liked: 951
  • Likes Given: 1251
Re: Latest PIOMAS update (June 2020)
« Reply #3287 on: June 08, 2020, 12:46:24 AM »
Here is another volume chart, in which 2020 is currently at record low. High Arctic seas, excluding the CAB and the CAA. Some of the extra CAB volume is balanced by missing volume in adjacent seas. What does it mean? I am not sure but at the end of the season we will learn some more.
I love that graph Oren! Those are the seas I look at for the melting season. I never look much at the CAA, Baffin, or other southern and peripheral seas. IMHO I don't think they matter much for the energy balance in the Arctic Ocean. Am I wrong about that? Water doesn't flow in that way, does it? It only flows out through the CAA...

I also think the CAB is in much worse shape than the numbers tell us. Time will tell if I'm right about that. I think the CAB will be polynyaficated a lot this season.  ;)
90% of the world is religious, but somehow "love thy neighbour" became "fuck thy neighbours", if they don't agree with your point of view.

WTF happened?

FishOutofWater

  • Nilas ice
  • Posts: 1088
    • View Profile
  • Liked: 696
  • Likes Given: 332
Re: Latest PIOMAS update (June 2020)
« Reply #3288 on: June 08, 2020, 01:20:50 AM »
The volume anomaly pattern is explained by the strong polar vortex and Arctic oscillation this past winter. There was strong cyclonic flow which brought Atlantic water into the Barents and Kara seas while compressing ice in the Beaufort sea and the CAA. Fresh water in the Beaufort gyre has been pushed towards the CAA.

The winter was disturbingly warm considering that the strong polar vortex kept cold air in the Arctic this winter. Don't expect the effects of the Atlantic water entering the European side of the Arctic to have impacts this year. It might, but Atlantic ocean heat can take years to impact the ice because the Atlantic water layer is 300m below the surface in much of the Arctic ocean. The impacts may be seen in following years.

Rod

  • Guest
Re: Latest PIOMAS update (June 2020)
« Reply #3289 on: June 08, 2020, 02:38:13 AM »
Following up on FOW’s comments, below is a map prepared by the University of Washington’s Polar Science Center that shows the locations of the thickness anomalies relative to recent years.

According to the PIOMAS model, 2020 is currently in 6th place.  However, as can be seen from the map, the areas where 2020 has its largest advantage are areas that will struggle to survive this melting season. 

The anomalously thick ice on the Atlantic front will be exported south where it will eventually melt. The anomalously thick ice north of the western CAA will be exported into the Beaufort or Amundsen Gulf where it will likely melt in situ. 

The CAB has a slight positive anomaly, but it seems to be overwhelmed by the negative anomalies in the ESS, Laptev and Kara. 

PIOMAS is a model. But it is a useful one.  The absolute values might not be correct, but the trends are important to watch. 

As people have repeatedly said, it is way too early in the season to make predictions about the ultimate minimum.  But what we can see is that the long term pattern is continuing to head in a very bad direction.
« Last Edit: June 08, 2020, 02:50:43 AM by Rod »

Freegrass

  • Young ice
  • Posts: 3825
  • Autodidacticism is a complicated word...
    • View Profile
  • Liked: 951
  • Likes Given: 1251
Re: Latest PIOMAS update (June 2020)
« Reply #3290 on: June 08, 2020, 03:16:12 AM »
Don't expect the effects of the Atlantic water entering the European side of the Arctic to have impacts this year. It might, but Atlantic ocean heat can take years to impact the ice because the Atlantic water layer is 300m below the surface in much of the Arctic ocean. The impacts may be seen in following years.
What about surface water that gets heated by the sun in the Barents and Kara seas? Doesn't that have a direct impact?
90% of the world is religious, but somehow "love thy neighbour" became "fuck thy neighbours", if they don't agree with your point of view.

WTF happened?

Rod

  • Guest
Re: Latest PIOMAS update (June 2020)
« Reply #3291 on: June 08, 2020, 03:28:10 AM »
I think he is talking about something different Freegrass.

He is discussing oceanography and potential Atlanticfication.  There is no doubt that surface water that gets heated has an important impact.

oren

  • Moderator
  • First-year ice
  • Posts: 9805
    • View Profile
  • Liked: 3584
  • Likes Given: 3922
Re: Latest PIOMAS update (June 2020)
« Reply #3292 on: June 08, 2020, 04:33:36 AM »
Following up on FOW’s comments, below is a map prepared by the University of Washington’s Polar Science Center that shows the locations of the thickness anomalies relative to recent years.

According to the PIOMAS model, 2020 is currently in 6th place.  However, as can be seen from the map, the areas where 2020 has its largest advantage are areas that will struggle to survive this melting season. 

The anomalously thick ice on the Atlantic front will be exported south where it will eventually melt. The anomalously thick ice north of the western CAA will be exported into the Beaufort or Amundsen Gulf where it will likely melt in situ. 

The CAB has a slight positive anomaly, but it seems to be overwhelmed by the negative anomalies in the ESS, Laptev and Kara. 

PIOMAS is a model. But it is a useful one.  The absolute values might not be correct, but the trends are important to watch. 

As people have repeatedly said, it is way too early in the season to make predictions about the ultimate minimum.  But what we can see is that the long term pattern is continuing to head in a very bad direction.
This map is the thing to watch. 2020 is balanced on the razor's edge of weather. Should a big push for export come along, the hugely positive anomaly north of Svalbard will slide down the Fram and to oblivion, leaving the CAB with mediocre volume and open to attack from the Siberian side with nothing to show for it. Otherwise, it could delay melt and protect the flank of the CAB from the Atlantic, while bolstering volume and reducing chances of new records.
The Beaufort volume anomaly is a different story. It will not be easy to get rid of it. Most probably it will move west and eventually melt, but this could delay melt progress towards the CAB in that sector.

Phoenix

  • Guest
Re: Latest PIOMAS update (June 2020)
« Reply #3293 on: June 08, 2020, 05:09:04 AM »
It would be interesting to know if there is anyone has tried to quantify the incremental impact of import / export on the minimum.

Wipneus has a nice chart which aims to quantify what is crossing the line into Fram and we can see that the peak rate in May was ~ 1,000 km3 / mo for very brief periods coinciding with the cyclone at Svalbard. There are also some instances where the rate goes negative.

So, let's say 200 km3 goes over the line in a month. If we want to project how much impact that makes on the minimum, we should probably apply a haircut for the amount that ice would have melted if the export had not occurred. If the exported ice is coming from a region which is expected to melt completely anyway, then it seems the export event is largely irrelevant to the minimum.

It would also be interesting to know how much export varies from over time.

My hunch is that export doesn't vary in amounts which are very material to the outcome. If that were the case, I think we'd see more volatility in the volume data from year to year. That period of the year from days 165 to 210 where CAB results are so consistent should be useful in detecting factors which are capable of big fluctuations.


uniquorn

  • First-year ice
  • Posts: 5117
    • View Profile
  • Liked: 2163
  • Likes Given: 388
Re: Latest PIOMAS update (June 2020)
« Reply #3294 on: June 08, 2020, 06:23:20 PM »
Animation of piomas, jun9 from 2000-2019 with may31 2020 (latest image)
The 4m ice, if it exists, does make 2020 look like a 'rebound' year. We'll see soon enough.
« Last Edit: June 08, 2020, 07:07:27 PM by uniquorn »

FishOutofWater

  • Nilas ice
  • Posts: 1088
    • View Profile
  • Liked: 696
  • Likes Given: 332
Re: Latest PIOMAS update (June 2020)
« Reply #3295 on: June 08, 2020, 07:07:08 PM »
In summer 2007 a strong Arctic dipole caused a large step decline in volume, Phoenix. You need to review professional research papers on sea ice especially ones that discuss 2007, 2010 and 2012.

The Beaufort gyre used to be where thick multiyear sea ice built up. The gyre did not go away, but the weather has warmed rapidly over the Beaufort sea, the Chukchi sea and northern Alaska at some of the highest warming rates on earth. Multiyear ice has declined rapidly because the Beaufort gyre is storing heat from one summer to the next.

That stored heat, combined with much above normal temperatures the past month, bodes ill for the positive ice volume anomaly in that region. If the weather continues to be warm, sunny high pressure that ice will be gone and the whole Arctic will be on thin ice.

This September's sea ice forecast is extremely challenging because the thick ice is near ice killing grounds if the weather favors melting .

Glen Koehler

  • Grease ice
  • Posts: 931
    • View Profile
  • Liked: 738
  • Likes Given: 1413
Re: Latest PIOMAS update (June 2020)
« Reply #3296 on: June 09, 2020, 02:44:37 PM »
    Thanks Uniquorn.  I think the animated 2010-2020 thickness map is the single best tracking tool we have.  I hope you keep doing them.  The timings were perfect for watching repeatedly.
« Last Edit: June 09, 2020, 03:15:39 PM by Glen Koehler »
“What is at stake.... Everything, I would say." ~ Julienne Stroeve

Phoenix

  • Guest
Re: Latest PIOMAS update (June 2020)
« Reply #3297 on: June 09, 2020, 03:18:22 PM »
Ditto on the appreciation for uniquorn's gif and the skills and topical interest which make them possible.





Wipneus

  • Citizen scientist
  • Young ice
  • Posts: 4220
    • View Profile
    • Arctische Pinguin
  • Liked: 1025
  • Likes Given: 0
Re: Latest PIOMAS update (June 2020, mid-monthly update)
« Reply #3298 on: June 18, 2020, 12:15:57 PM »
PIOMAS gridded thickness data was updated to day 167 (15/16th  of June). Calculated volume on that day was 16.734 [1000 km3], 6th lowest for the day.

Here is the animation of this year's "june cliff" in progress.

Wipneus

  • Citizen scientist
  • Young ice
  • Posts: 4220
    • View Profile
    • Arctische Pinguin
  • Liked: 1025
  • Likes Given: 0
Re: Latest PIOMAS update (June 2020, mid-monthly update)
« Reply #3299 on: June 18, 2020, 12:17:35 PM »
Updated volume and volume-anomaly graphs. Click to size.