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Author Topic: Latest PIOMAS update (October, mid month update)  (Read 615377 times)

jai mitchell

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Re: Latest PIOMAS update (March)
« Reply #1500 on: March 17, 2017, 05:16:13 PM »
the graphs need to be normalized to current total volume, as a percent of total volume, not absolute numbers.  otherwise they give a false indicator.
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magnamentis

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Re: Latest PIOMAS update (March)
« Reply #1501 on: March 17, 2017, 05:41:59 PM »
the graphs need to be normalized to current total volume, as a percent of total volume, not absolute numbers.  otherwise they give a false indicator.

absolutely, very much self evident but can easily be overseen, 50% of volume exported of 25% of volume left is double the loss or something like that LOL

thanks for hinting
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FishOutofWater

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Re: Latest PIOMAS update (March)
« Reply #1502 on: March 17, 2017, 05:45:30 PM »
Irregularly updated: the monthly Fram export graphs. The low volume numbers of late do not seem to be caused by higher than usual Fram exports.

Since these graphs are based on average monthly thickness and velocity numbers, I have some doubts about their validity. Daily numbers are available now, at some time I intend to uses these.

Just, wow, Wip. Fall 2016 through now shows a very delayed Fram export curve.  However, the Arctic Oscillation has been cyclonic, favoring export. That leads me to conclude, based also on observations of it happening, that ice melted out before it ever got to the Fram. It was exported as fresh water.

Tor Bejnar

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Re: Latest PIOMAS update (March)
« Reply #1503 on: March 17, 2017, 06:15:11 PM »
Remember: during most of the NH autumn and winter, much of the ice heading towards the Fram melted before it got there!
Arctic ice is healthy for children and other living things.

jai mitchell

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Re: Latest PIOMAS update (March)
« Reply #1504 on: March 18, 2017, 06:59:17 PM »
I like the export graphs though, really top notch and worth peer review in my book.  just saying that for a year on year predictive value it would be better to have it graphed as a percent of total current volume.  I believe that this would show this year being slightly higher than previous years.
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Jim Hunt

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Re: Latest PIOMAS update (March)
« Reply #1505 on: March 18, 2017, 08:02:41 PM »
I believe that this would show this year being slightly higher than previous years.

This years numbers should be getting a boost:

http://GreatWhiteCon.info/2017/03/facts-about-the-arctic-in-march-2017/#comment-219974
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magnamentis

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Re: Latest PIOMAS update (March)
« Reply #1506 on: March 19, 2017, 06:39:56 PM »
I like the export graphs though, really top notch and worth peer review in my book.  just saying that for a year on year predictive value it would be better to have it graphed as a percent of total current volume.  I believe that this would show this year being slightly higher than previous years.

significantly higher IMO but i understand that you wanted to stay careful LOL :D ;)
« Last Edit: March 22, 2017, 04:32:15 PM by magnamentis »
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crandles

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Re: Latest PIOMAS update (March)
« Reply #1507 on: March 22, 2017, 04:14:56 PM »
Latest daily volume numbers file while official site is not providing it.

Edit. Sorry should have said nothing new in here, really just making available for PaulS at stoat's site who couldn't get at data from psc site and still seems to be unavailable from there.
« Last Edit: March 23, 2017, 12:34:46 AM by crandles »

Jim Williams

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Re: Latest PIOMAS update (March)
« Reply #1508 on: March 22, 2017, 05:14:18 PM »
Latest daily volume numbers file while official site is not providing it.
Same file cleaned up in Google Sheets and re-exported as CSV.  (It is a .CSV file, but I could not upload that type so I renamed it as txt.)  No idea what I am going to do with it now that I have it, but I figured it would be an easier format for many to deal with.

As an aside, I know it is an artifact of the decimal system and the units of measurement but the way vol under 10 showed up as a new column I had to clean up and then increased in size was striking.

Tigertown

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Re: Latest PIOMAS update (March)
« Reply #1509 on: March 22, 2017, 11:37:46 PM »
Latest daily volume numbers file while official site is not providing it.
The last update is for Feb. 28th in this file, which we have already.


P.S. I would make an educated guess that PIOMAS  is around 20.5k km3 right now and currently dropping.
« Last Edit: March 23, 2017, 12:03:42 AM by Tigertown »

Lord M Vader

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Re: Latest PIOMAS update (March)
« Reply #1510 on: April 04, 2017, 09:34:48 PM »
PIOMAS is updated! Here are the graphs for March:






dosibl

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Re: Latest PIOMAS update (March)
« Reply #1511 on: April 04, 2017, 09:36:25 PM »
They didn't update the thumbnail, I've been staring at it all day!

Average thickness chart looks a little troubling.

RikW

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Re: Latest PIOMAS update (March)
« Reply #1512 on: April 04, 2017, 09:41:32 PM »
They didn't update the thumbnail, I've been staring at it all day!

Average thickness chart looks a little troubling.
Yeah, it look likes it's flattening too early

dosibl

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Re: Latest PIOMAS update (March)
« Reply #1513 on: April 04, 2017, 09:48:28 PM »
The X axis starting before January really throws me off with these graphs, is the graphed data through the middle of March or all of March?

Lord M Vader

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Re: Latest PIOMAS update (March)
« Reply #1514 on: April 04, 2017, 09:55:06 PM »
Interesting that Beaufort Sea depicts some thicker ice than usual. And the thick ice blob that is close to Fram.... It is a miracle if it manages to stay in the Arctic through the melting season.

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Re: Latest PIOMAS update (March)
« Reply #1515 on: April 04, 2017, 10:22:21 PM »
I have updated all of my PIOMAS sea ice volume and thickness plots at http://sites.uci.edu/zlabe/arctic-sea-ice-volumethickness/ through March 2017
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Tigertown

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Re: Latest PIOMAS update (March)
« Reply #1516 on: April 04, 2017, 10:49:51 PM »
Latest daily volume numbers file while official site is not providing it.
The last update is for Feb. 28th in this file, which we have already.


P.S. I would make an educated guess that PIOMAS  is around 20.5k km3 right now and currently dropping.
Who would have thunk it. I was a little too high on my guess.
« Last Edit: April 04, 2017, 11:30:02 PM by Tigertown »

FishOutofWater

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Re: Latest PIOMAS update (March)
« Reply #1517 on: April 04, 2017, 11:24:22 PM »
I have updated all of my PIOMAS sea ice volume and thickness plots at http://sites.uci.edu/zlabe/arctic-sea-ice-volumethickness/ through March 2017

Thanks, Zach. Your first animation of March sea ice decline is disturbing. The thickest ice is piling up on the way out the Fram strait. This is a catastrophe in the making.

The atmosphere is also switching to summer mode as the stratospheric polar vortex goes into it's final warming for the spring and high pressure sets up over the Beaufort for the coming weeks. We're going to see rapid ice loss in the Beaufort as warm high pressure and intense sun heat the atmosphere.

DavidR

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Re: Latest PIOMAS update (March)
« Reply #1518 on: April 04, 2017, 11:29:18 PM »
The X axis starting before January really throws me off with these graphs, is the graphed data through the middle of March or all of March?

The X axis starts at the befginning of January and provides the daily data.  The marked points (Jan, Feb, Mar) are the monthly averages.

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Re: Latest PIOMAS update (March)
« Reply #1519 on: April 04, 2017, 11:40:26 PM »
Really troubling. The energy required for a meltout is at reach of the two or three worst summers in the last ten years, not just 2012. A 2007-like might end it too, the '15 and '16 summers also saw a strong volume decline.
But small details count, early cracks, warm spells, ocean currents... sun or storms? Can amplify the heat or mitigate the feedbacks.
Another gloomy start of the melting season.

crandles

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Re: Latest PIOMAS update (March)
« Reply #1520 on: April 05, 2017, 12:03:04 AM »
Year  Day  Volume K Km3
2017  90  20.398 below previous record by 1.731
2011  90  22.129 below previous record by 1.582
2016  90  22.330
2014  90  22.639
2013  90  22.850
2012  90  22.889
2007  90  23.711 below previous record by 1.149
2015  90  24.040
2010  90  24.053
2009  90  24.613
2008  90  24.698
2006  90  24.860

Last month
2017  59  18.608 1.851
2011  59  20.459

So a fairly marginal narrowing of gap from 1.851 down to 1.731

crandles

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Re: Latest PIOMAS update (March)
« Reply #1521 on: April 05, 2017, 12:10:30 AM »

The X axis starts at the befginning of January and provides the daily data.  The marked points (Jan, Feb, Mar) are the monthly averages.

Looks to me like marked points are mid month values rather than monthly average. April average value would be well below the maximum value during month. (similar for Sept)

Adam Ash

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Re: Latest PIOMAS update (March)
« Reply #1522 on: April 05, 2017, 01:22:48 AM »
Really troubling. The energy required for a meltout is at reach of the two or three worst summers in the last ten years, not just 2012. A 2007-like might end it too, the '15 and '16 summers also saw a strong volume decline.
But small details count, early cracks, warm spells, ocean currents... sun or storms? Can amplify the heat or mitigate the feedbacks.
Another gloomy start of the melting season.

Indeed!  A simple drag and drop of previous years shows the potential for a far-too-close-for comfort minimum.

Tigertown

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Re: Latest PIOMAS update (March)
« Reply #1523 on: April 05, 2017, 01:42:01 AM »
Adam Ash
Indeed!  A simple drag and drop of previous years shows the potential for a far-too-close-for comfort minimum.
That smells like a Blue Ocean Event.

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Re: Latest PIOMAS update (March)
« Reply #1524 on: April 05, 2017, 01:43:20 AM »
Adam Ash
Indeed!  A simple drag and drop of previous years shows the potential for a far-too-close-for comfort minimum.
That smells like a Blue Ocean Event.

The fat singing lady always makes her own damn mind  ;)
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Re: Latest PIOMAS update (March)
« Reply #1525 on: April 05, 2017, 05:00:49 AM »
Adam Ash
Indeed!  A simple drag and drop of previous years shows the potential for a far-too-close-for comfort minimum.
That smells like a Blue Ocean Event.

The fat singing lady always makes her own damn mind  ;)
Indeed.  No prediction of Blue Ocean here until after I see the numbers at the end of May.  Far too much depends on weather and albedo.
This space for Rent.

Adam Ash

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Re: Latest PIOMAS update (March)
« Reply #1526 on: April 05, 2017, 05:36:47 AM »
Sure, but if that was a chart of your domestic finances (or your pulse rate over time) then you would be fillin' yer pants!  I know there are many ways mother nature can swing to avoid big blue, but I respectfully suggest that a little anxiety is in order.  Problem is, of course, that the anxiety of the good folk here will not translate into any meaningful action on GHG emissions.  End result of these musings can only be deepening despair.  On a brighter note, parts of my country have just had individual 100-year rain storms, several days in a row.  As they say, "Nothing to see here, move on!"  Sigh.  Sorry Neven, back to topic...

Adam Ash

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Re: Latest PIOMAS update (March)
« Reply #1527 on: April 05, 2017, 05:56:47 AM »
...and assuming 2017 Max Volume is as of today, then a 2012 melt will see intrepid explorers having to search far and wide for any ice at all, at all, to go with their Scotch.
« Last Edit: April 05, 2017, 10:31:36 AM by Adam Ash »

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Re: Latest PIOMAS update (April)
« Reply #1528 on: April 05, 2017, 06:52:33 AM »
I updated my graphics, see the top post

Attached my year-by-year anomaly graph showing the strong negative anomaly  changed little in March.

Wipneus

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Re: Latest PIOMAS update (April)
« Reply #1529 on: April 05, 2017, 06:54:22 AM »
Gridded thickness updated as well. Here is the animation for March.

oren

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Re: Latest PIOMAS update (April)
« Reply #1530 on: April 05, 2017, 07:01:43 AM »
End-March volume. The thickening Beaufort and CAB couldn't offset the blob heading into the Fram, and the 6-year "plateau" waved goodbye.

Tigertown

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Re: Latest PIOMAS update (April)
« Reply #1531 on: April 05, 2017, 07:18:49 AM »
Export in the near future seems like it is going to not only take a bite out of the volume directly, but will soon start to make way for a lot of km2's of open water ready to absorb energy, and early on in the season at that. Momentum being key.
So, whether predictions are in order or not, the situation certainly calls for grave concern. There may be some serious teleconnection problems coming our way.

seaicesailor

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Re: Latest PIOMAS update (April)
« Reply #1532 on: April 05, 2017, 09:56:44 AM »
Chris Reynolds no longer updates on the regional GICE thickness distributions of PIOMAS but it would be of great interest right now. I might give it a try if I find the time, but no expert on post-processing gridded stuff. If anybody has the guts (and the time...) :-)

Neven

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Re: Latest PIOMAS update (April)
« Reply #1533 on: April 05, 2017, 01:49:16 PM »
I have posted the latest PIOMAS update on the ASIB.

Final part may be of interest:

The volume maximum is going to be reached this month (a bit later than extent because ice is still thickening at more northern latitudes). Below is a table that shows the maximums for the past 10 years, and next to that the potential 2017 maximum if it gains as much volume as those years did between end of March and their respective maximums:



The average of all those potential maximums for 2017 is 20795 km3. Now, the average of total melt for the past 10 years is 18269 km3, which means that at the end of this year's melting season the minimum could be only 2526 km3 (the lowest minimum on record reached in 2012 was 3673 km3). If we take the lowest amount of volume growth since the end of March (2007), and subtract the highest total melt (19693 km3 in 2010) from that potential maximum, the minimum could even go lower than 1 million km3!

But that's just numbers. Even though it shows the theoretically possible, we'll have to wait and see what the weather brings this melting season. Suffice to say that it would take some crazy circumstances for this theoretical extreme to become practice.
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Archimid

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Re: Latest PIOMAS update (April)
« Reply #1534 on: April 05, 2017, 01:54:59 PM »
Whether a blue ocean event is reached or not, our civilization shouldn't have exposed itself to this risk.
I am an energy reservoir seemingly intent on lowering entropy for self preservation.

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Re: Latest PIOMAS update (April)
« Reply #1535 on: April 05, 2017, 02:13:07 PM »
I have posted the latest PIOMAS update on the ASIB.

Final part may be of interest:

Just using the 2017 Max based on 2016......produces a 8.5% drop from the 2016 max.  THAT....is good chunk of ice.

2016 ACTUAL MAX      = 22,717
2017 "Forecast" Max   = 20,790

Difference =  1,927 which is 8.5% of 22,717

 
« Last Edit: April 05, 2017, 08:34:58 PM by Buddy »
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Jim Pettit

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Re: Latest PIOMAS update (April)
« Reply #1536 on: April 05, 2017, 02:20:13 PM »
I've updated all my PIOMAS volume graphs (https://sites.google.com/view/pettitclimategraphs). Of particular interest are these two. The first shows that 2017 is maintaining its large lead over all other years:



And this second shows where 2017 volume might end up if it were to follow the trajectories of the other years in the record. There are no "blue ocean" events on tap, but following 2010's behavior the rest of the way, for instance, would render a minimum of under 1,000 km3. In fact, a repeat of the 07-16 average would keep 2017 below the 2012 record for nearly two full months, and wind up with about 2,300 km3.



Whatever happens: hold onto your hats...

Wipneus

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Re: Latest PIOMAS update (April)
« Reply #1537 on: April 05, 2017, 03:34:54 PM »
The March 31 thickness map, compared with previous years and the thickness-differences.
Clicks for size.

oren

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Re: Latest PIOMAS update (April)
« Reply #1538 on: April 05, 2017, 05:18:13 PM »
I have posted the latest PIOMAS update on the ASIB.

Final part may be of interest:
Neven - thanks for another interesting monthly update (and the hat tip  :) ). Just note the typo - "the minimum could even go lower than 1 million km3" should be 1000 km3 of course.

Neven

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Re: Latest PIOMAS update (April)
« Reply #1539 on: April 05, 2017, 06:08:43 PM »
God, I'm so stupid. Thanks, oren.  :)

And thanks for the graph.
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Jim Pettit

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Re: Latest PIOMAS update (April)
« Reply #1540 on: April 05, 2017, 06:49:32 PM »
Neven - thanks for another interesting monthly update (and the hat tip  :) ). Just note the typo - "the minimum could even go lower than 1 million km3" should be 1000 km3 of course.

1 million km3 is a lot, about enough to cover the entire surface of the planet in nearly two meters (6'5") of ice.

Don't tell Anthony Watts... :)

meddoc

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Re: Latest PIOMAS update (April)
« Reply #1541 on: April 05, 2017, 08:28:03 PM »
Whether a blue ocean event is reached or not, our civilization shouldn't have exposed itself to this risk.

Gee, You are dam' selfish.
What about countless other species; and You are worried about the destructive, killing machine, heat engine called civilization...

slow wing

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Re: Latest PIOMAS update (April)
« Reply #1542 on: April 05, 2017, 11:24:04 PM »
Thanks for the update Wipneus, much appreciated.

Those year-to-year differences maps for 31 March are telling: the ice appears in worse shape this year than in any of the previous years shown, apart from that blob of thick ice poised over Fram Strait.
« Last Edit: April 06, 2017, 12:00:30 AM by slow wing »

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Re: Latest PIOMAS update (April)
« Reply #1543 on: April 06, 2017, 11:21:24 AM »
If one compares the March volume with the linear trend, one could say that volume reduction is about 4 years ahead of schedule. This points more to accelerated slow transition rather than imminent collapse ?
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crandles

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Re: Latest PIOMAS update (April)
« Reply #1544 on: April 06, 2017, 12:15:42 PM »
If one compares the March volume with the linear trend, one could say that volume reduction is about 4 years ahead of schedule. This points more to accelerated slow transition rather than imminent collapse ?

Why not still slow transition but with a one off outlier year? Or ....

Richard Rathbone

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Re: Latest PIOMAS update (April)
« Reply #1545 on: April 06, 2017, 01:22:48 PM »
If one compares the March volume with the linear trend, one could say that volume reduction is about 4 years ahead of schedule. This points more to accelerated slow transition rather than imminent collapse ?

Why not still slow transition but with a one off outlier year? Or ....

Its not even a one-off. The anomaly is now about 1 STD below trend which is low but not spectacularly so. 2007 and 2011 were in a similar place. There were records then and I expect there will be record minimums this year, but 1 STD below trend is no evidence at all of acceleration in trend.

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Re: Latest PIOMAS update (April)
« Reply #1546 on: April 06, 2017, 02:12:56 PM »
I have a simple mind.....I need a simple picture:

1)  Each year we have MORE OCEAN WATER....AND......LESS ICE (8.5% less this yr)
2)  And each year that slightly larger quantity of ocean water is also SLIGHTLY WARMER
3)  So that "extra energy" is attacking a smaller and smaller body of ice

My simple (and not scientifically trained mind) tells me the remaining ice volume will disappear much more quickly than many people suspect.   Things like "storms" have got to be pretty tough to "model".  Remember.....the models 5 years ago said not to worry until 2050 - 2100.

I wouldn't be surprised to see something in the range of 3,000 KM3 this year OR LOWER.. (where that "black dot" is in September).  The only significant MYI is along the coast of the Canadian Archipelago.  Ice is now more and more susceptible to weather, currents, storms....etc.  And "ill timed storm"....and there goes a lot of ice.

I think we will get to THIS YEAR....where I "thought" me might get LAST YEAR.  And that is the only significant ice is north of the Canadian Archipelago going east to the northern Greenland shores..  By 2020 or 2021.....almost entirely BLUE WATER in the Arctic in September.



   

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oren

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Re: Latest PIOMAS update (April)
« Reply #1547 on: April 06, 2017, 02:29:11 PM »
If one compares the March volume with the linear trend, one could say that volume reduction is about 4 years ahead of schedule. This points more to accelerated slow transition rather than imminent collapse ?

Why not still slow transition but with a one off outlier year? Or ....

Its not even a one-off. The anomaly is now about 1 STD below trend which is low but not spectacularly so. 2007 and 2011 were in a similar place. There were records then and I expect there will be record minimums this year, but 1 STD below trend is no evidence at all of acceleration in trend.
Just to be clear, the "slow transition" theory postulated that summer sea ice in the arctic will slowly transition to a seasonally ice-free state instead of a tipping point and immediate collapse - this due to a plateau in winter sea ice after the MYI has largely gone and thanks to almost-constant FDDs.
The plateau held for a few years, but the FDD assumption proved incorrect in reality and the plateau was broken cleanly this year. Will FDDs continue to exhibit such large anomalies, or is this a one-time outlier? Good question. I suspect the FDD deficit is systemic and partly a result of feedback from the enthalpy accumulated in the previous melting season, and therefore that the slow transition claim is invalid.
On the other hand, I agree winter volume is showing a linear trend with no acceleration.

crandles

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Re: Latest PIOMAS update (April)
« Reply #1548 on: April 06, 2017, 03:40:45 PM »
Just to be clear, the "slow transition" theory postulated ... this due to a plateau in winter sea ice after the MYI has largely gone and thanks to almost-constant FDDs.
...  plateau was broken cleanly this year

Not sure I quite agree with that. I thought slow transition allowed for continuing slow decline in FDD due to increasing GHGs and increase heat transport from lower latitudes. This would lead to slow decline in thermodynamic max thickness and therefore maximum volume continues to decline but at a slower rate rather than the fast volume decline when thick MYI was rapidly being replaced by thinner FYI.


This would make the deviation in max volume from expected slow transition trend larger than 1SD which is nothing unusual at all to something larger but I think it is still well within realms of possibility and thus not ruled out.

The off trend decline in max volume is caused by off trend FDD number. So rather than calculating how far off max volume is (awkward with changing trend), perhaps it is more relevant to ask how far off trend is the FDD number?

S.Pansa

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Re: Latest PIOMAS update (April)
« Reply #1549 on: April 06, 2017, 04:37:37 PM »
I liked the idea of a slow transition when I first read it. But is there really any evidence--as of yet---that this slow transition - a slowdown in the steady decline of the winter volume max - is happening?

If we have a look at the PIOMASS figure below, I don't think there is.
From 2007 onwards, nearly every year is dead on or below the linear trend of -2.6 [1.000km³/decade] for the April volume - only exception 2014.
From Nevens blog post I gather that 2017 will most likely come in below 21.000 km³, which would again fall below the trend line (perhaps an outlier like 2007). I am not arguing that there is an acceleration. But neither do I see any slowdown. What am I missing?