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Author Topic: Latest PIOMAS update (July 2020)  (Read 1191062 times)

viddaloo

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Re: Latest PIOMAS update (December)
« Reply #450 on: December 08, 2014, 07:44:53 AM »
I don't think removing the last half of the ice is any more bold than removing the first half that was lost from 1979 to 2014. Did anyone in 1979 think that would happen? No. At that time they were talking about a new ice age, and any talk of massive ice–loss was just preposterous.

However, I'm glad that you and Mr Math comment on it. Humans make mistakes, and last time I checked the mirror, I looked very much like one of them humans. That means I can make mistakes. If I have in any way made mathematical mistakes by calculating the average volume, I would like you to point it out. If your objection is about the trendline, then please suggest a different sort of trendline that you believe is more plausible, plus the reasoning behind this.

Mine is
Code: [Select]

trendlines: {
   0: {
        type: 'polynomial',
        degree: 2,       
        visibleInLegend: false,
        color: 'green',
   },
}
[]

Peter Ellis

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Re: Latest PIOMAS update (December)
« Reply #451 on: December 08, 2014, 09:48:12 AM »
I don't know why many of you assume such things. IMO none of you have explained this sufficiently. In 2013 you had 365 days. Each of those days had their total ice volume figure. Add day 1 + day 2 ... + day 365 into a year total and divide by 365. Et voila!

Yes, but you are then projecting that forward, and you need to be clear in your own mind (and in your posts) about what that projection entails. When you predict that (say) 2020 will be 3.5x10^6 km^3 lower than 2015, how is that actually playing out in terms of day to day volume? 

Do you think that every individual day will be 3.5x10^6 km^3 lower than the corresponding day 5 years previously (i.e. March 1st 2020 is 3.5x10^6 lower than April 1st 2015, September 1st 2020 is 3.5x10^6 lower than September 1st 2015, etc.)? 

Or will the losses be concentrated more in summer or winter?

If you start to think in genuine physical terms you'll see the problem - you predict that 2031 will be ~14x10^6 lower than today.  But the current rate of decline is based on curves that are getting lower all year (and summer declining faster than winter).  If you lower everything across the board by 14x10^6, you go negative in summer!  At some point these losses are going to start flattening out because of this effect.

viddaloo

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Re: Latest PIOMAS update (December)
« Reply #452 on: December 08, 2014, 11:30:09 AM »
Peter, I guess this — and the collapse graph — should more appropriately be discussed over at the Annual Average Thread. As I've said I'm happy to discuss it, but I think right now it takes up too much space in this PIOMAS update thread, so better to discuss it in an on–topic thread for yearly averages.

I'll answer you there later today after some other — real world — business  ;D
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crandles

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Re: Latest PIOMAS update (December)
« Reply #453 on: December 08, 2014, 03:00:39 PM »
Did anyone in 1979 think that would happen? No. At that time they were talking about a new ice age, and any talk of massive ice–loss was just preposterous.

Not so for scientists re expecting global cooling. Though perhaps the media liked it as a scare story.

http://journals.ametsoc.org/doi/abs/10.1175/2008BAMS2370.1

Quote
An enduring popular myth suggests that in the 1970s the climate science community was predicting “global cooling” and an “imminent” ice age, an observation frequently used by those who would undermine what climate scientists say today about the prospect of global warming. A review of the literature suggests that, on the contrary, greenhouse warming even then dominated scientists' thinking as being one of the most important forces shaping Earth's climate on human time scales.






Neven

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Re: Latest PIOMAS update (November)
« Reply #454 on: December 16, 2014, 12:19:14 AM »
Here are thickness maps for October 2013 and 2014 as well as their difference.


I just posted a blog post over on the ASIB with some new CryoSat maps:



I know there have always been some discrepancies between PIOMAS and CryoSat, but the 2014-2013 difference between both graphs is quite pronounced, with CryoSat showing a lot less thick ice (red) this winter compared to last year's map. Whereas with PIOMAS it's the other way round.

Am I misinterpreting the maps? Did the CryoSat people accidentally swap the maps for 2013 and 2014?
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viddaloo

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Re: Latest PIOMAS update (November)
« Reply #455 on: December 16, 2014, 12:24:05 AM »
Am I misinterpreting the maps? Did the CryoSat people accidentally swap the maps for 2013 and 2014?

No idea what happened there, Neven, but they don't seem to be swapped, at least: You clearly see the big extra ice area between Svalbard and Josef's land on the 2014 map, which is correct (and was not there last year).
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Neven

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Re: Latest PIOMAS update (November)
« Reply #456 on: December 16, 2014, 12:28:44 AM »
Am I misinterpreting the maps? Did the CryoSat people accidentally swap the maps for 2013 and 2014?

No idea what happened there, Neven, but they don't seem to be swapped, at least: You clearly see the big extra ice area between Svalbard and Josef's land on the 2014 map, which is correct (and was not there last year).

Yes, indeed, that's the yellow on the CryoSat map. It's mostly the red that is causing the frown.
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viddaloo

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Re: Latest PIOMAS update (December)
« Reply #457 on: December 16, 2014, 12:41:50 AM »
Quote from: BBC
The spacecraft observed 7,500 cu km of ice cover in October when the Arctic traditionally starts its post-summer freeze-up.

This was only slightly down on 2013 when 8,800 cu km were recorded.

That's interesting, as PIOMAS never has October near 8,800 (not even on October 30th) in 2013, while PIOMAS' October 2014 crosses 7,500 already on the 9th (and ends at 9,700 on the 30th):

Code: [Select]
2013 274 5.79 2014 7.15
2013 275 5.82 2014 7.19
2013 276 5.84 2014 7.23
2013 277 5.86 2014 7.28
2013 278 5.92 2014 7.33
2013 279 5.99 2014 7.38
2013 280 6.08 2014 7.43
2013 281 6.15 2014 7.49
2013 282 6.24 2014 7.55
2013 283 6.33 2014 7.61
2013 284 6.42 2014 7.69
2013 285 6.52 2014 7.77
2013 286 6.63 2014 7.85
2013 287 6.75 2014 7.94
2013 288 6.88 2014 8.02
2013 289 7 2014 8.09
2013 290 7.09 2014 8.17
2013 291 7.16 2014 8.28
2013 292 7.27 2014 8.38
2013 293 7.36 2014 8.48
2013 294 7.46 2014 8.6
2013 295 7.57 2014 8.69
2013 296 7.66 2014 8.78
2013 297 7.74 2014 8.85
2013 298 7.84 2014 8.95
2013 299 7.96 2014 9.03
2013 300 8.06 2014 9.11
2013 301 8.16 2014 9.22
2013 302 8.29 2014 9.36
2013 303 8.44 2014 9.52
2013 304 8.59 2014 9.7
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Neven

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Re: Latest PIOMAS update (December)
« Reply #458 on: December 16, 2014, 01:16:51 AM »
I forgot the details, but I believe there are differences in total area that is counted by either PIOMAS or CryoSat. It's explained somewhere on the blog. So that shouldn't necessarily ring any bells.
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viddaloo

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Re: Latest PIOMAS update (December)
« Reply #459 on: December 16, 2014, 01:28:50 AM »
Looking at the numbers in my previous comment, it is more likely that the egg is on BBC's face, and that their summary should read:

Quote from: Fictional competent BBC reporter
The spacecraft observed 8,800 cu km of ice cover in October when the Arctic traditionally starts its post-summer freeze-up.

This was only slightly up from 2013 when 7,500 cu km were recorded.
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Neven

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Re: Latest PIOMAS update (December)
« Reply #460 on: December 16, 2014, 01:35:35 AM »
Looking at the numbers in my previous comment, it is more likely that the egg is on BBC's face, and that their summary should read:

Quote from: Fictional competent BBC reporter
The spacecraft observed 8,800 cu km of ice cover in October when the Arctic traditionally starts its post-summer freeze-up.

This was only slightly up from 2013 when 7,500 cu km were recorded.

But that still doesn't explain the graphs.

I guess we'll have to wait for wipneus and see what he thinks.
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crandles

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Re: Latest PIOMAS update (December)
« Reply #461 on: December 16, 2014, 01:46:47 AM »
I forgot the details, but I believe there are differences in total area that is counted by either PIOMAS or CryoSat. It's explained somewhere on the blog. So that shouldn't necessarily ring any bells.

I wouldn't have thought area would make any difference for Oct/Nov. It might nearer maximum ice volume.

PIOMAS (line & circles) v Cryosat2 (triangles)

Have we had any update on this graph?


https://earth.esa.int/web/guest/missions/esa-operational-eo-missions/cryosat/news/-/article/cryosat-extends-its-reach-on-the-arctic
Quote
Measurements made during October and November show that the volume of Arctic sea ice now stands at about 10,200 cubic km - a small drop compared to last year's 10,900 cubic km
.


Wipneus

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Re: Latest PIOMAS update (December)
« Reply #463 on: December 16, 2014, 10:49:14 AM »

But that still doesn't explain the graphs.

I guess we'll have to wait for wipneus and see what he thinks.

My first thought was that I never quite trusted the CS2 2013 October data. If I remember correctly half of the time the CS2 was shutdown and the operators were trying to rescue the satellite. I don't know how they filled in that permanently lost data.

If that is not the case, it is a strong reminder of the uncertainty in the data. Neither PIOMAS of Cryosat seems to be in a position to have the benefit of the doubt when there is a mismatch.

https://forum.arctic-sea-ice.net/index.php/topic,8.msg15924.html#msg15924

Neven

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Re: Latest PIOMAS update (December)
« Reply #464 on: December 16, 2014, 12:03:56 PM »
Here's the post I did last year, and back then the graphs looked like this (they changed the legend's colour scheme):

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Steven

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Re: Latest PIOMAS update (December)
« Reply #465 on: December 16, 2014, 09:34:49 PM »
I forgot the details, but I believe there are differences in total area that is counted by either PIOMAS or CryoSat. It's explained somewhere on the blog. So that shouldn't necessarily ring any bells.

Here is the domain over which the sea ice volume is usually calculated in the context of CryoSat  (and also for the earlier ICESat satellite).  It excludes regions like Kara, Barents, Greenland Sea, and Canadian Archipelago:



I used Chris Reynolds' regional volume data to estimate the PIOMAS volume inside and outside this domain respectively.

October PIOMAS volume:

Code: [Select]

year    volume_inside (km^3)   volume_outside (km^3)
2010    5657                   541
2011    5220                   499
2012    4578                   423
2013    6349                   604
2014    7192                   966


November PIOMAS volume:

Code: [Select]

year    volume_inside (km^3)   volume_outside (km^3)
2010    7916                   1564
2011    7745                   1505     
2012    7036                   1180
2013    8430                   1645
2014    9306                   2174

ChrisReynolds

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Re: Latest PIOMAS update (December)
« Reply #466 on: December 16, 2014, 09:53:43 PM »
Thanks Steven,

diablobanquisa

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Re: Latest PIOMAS update (December)
« Reply #467 on: December 17, 2014, 01:34:06 AM »
Cryosat-2 October-November data:
2010  8283 km3    (Laxon et al. 2013)
2011  6838 km3    (Laxon et al. 2013)
2012     ??              (Not published)
2013  10900 km3  (ESA 2014)
2014  10200 km3  (ESA 2014)

Cryosat-2 October data:
2010   ??            (Not published)
2011 5300 km3 (BBC 2014)
2012 5400 km3 (BBC 2014) (6000 km3 ??  ESA and BBC 2013)
2013 8800 km3 (BBC 2014) (9000 km3 ??  ESA and BBC 2013)
2014 7500 km3 (BBC 2014)

ESA 2013:
Quote
In October 2013, CryoSat measured about 9000 cubic km of sea ice – a notable increase compared to 6000 cubic km in October 2012

ESA 2014:
Quote
Measurements made during October and November show that the volume of Arctic sea ice now stands at about 10 200 cubic km – a small drop compared to last year’s 10 900 cubic km.

BBC 2014:
Quote
The spacecraft observed 7,500 cu km of ice cover in October when the Arctic traditionally starts its post-summer freeze-up. This was only slightly down on 2013 when 8,800 cu km were recorded. The deep lows in this short series were 5,300 and 5,400 cubic km in 2011 and 2012, respectively.

BBC 2013:
Quote
In the three years following its launch, the spacecraft saw a steady decline in autumn ice volume, with a record low of 6,000 cubic km being recorded in late October 2012. But after a sharply colder summer this year, the autumn volume number has gone up. Measurements taken in the same three weeks in October found the floes to contain just shy of 9,000 cu km.


Laxon et al. 2013:  http://psc.apl.washington.edu/zhang/Pubs/Laxon_etal2013_icevol_grl50193.pdf (look at Table 1)


A little chaotic...  :o
« Last Edit: December 17, 2014, 02:03:04 AM by diablobanquisa »

Neven

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Re: Latest PIOMAS update (December)
« Reply #468 on: December 17, 2014, 10:00:10 AM »
Cryosat-2 October-November data:
2010  8283 km3    (Laxon et al. 2013)
2011  6838 km3    (Laxon et al. 2013)
2012     ??              (Not published)
2013  10900 km3  (ESA 2014)
2014  10200 km3  (ESA 2014)

Cryosat-2 October data:
2010   ??            (Not published)
2011 5300 km3 (BBC 2014)
2012 5400 km3 (BBC 2014) (6000 km3 ??  ESA and BBC 2013)
2013 8800 km3 (BBC 2014) (9000 km3 ??  ESA and BBC 2013)
2014 7500 km3 (BBC 2014)

ESA 2013:
Quote
In October 2013, CryoSat measured about 9000 cubic km of sea ice – a notable increase compared to 6000 cubic km in October 2012

ESA 2014:
Quote
Measurements made during October and November show that the volume of Arctic sea ice now stands at about 10 200 cubic km – a small drop compared to last year’s 10 900 cubic km.

BBC 2014:
Quote
The spacecraft observed 7,500 cu km of ice cover in October when the Arctic traditionally starts its post-summer freeze-up. This was only slightly down on 2013 when 8,800 cu km were recorded. The deep lows in this short series were 5,300 and 5,400 cubic km in 2011 and 2012, respectively.

BBC 2013:
Quote
In the three years following its launch, the spacecraft saw a steady decline in autumn ice volume, with a record low of 6,000 cubic km being recorded in late October 2012. But after a sharply colder summer this year, the autumn volume number has gone up. Measurements taken in the same three weeks in October found the floes to contain just shy of 9,000 cu km.


Laxon et al. 2013:  http://psc.apl.washington.edu/zhang/Pubs/Laxon_etal2013_icevol_grl50193.pdf (look at Table 1)


A little chaotic...  :o

You can say that again. Every year different maps with different legends as well.

I'm tempted to say that CryoSat is perhaps not delivering what was hoped for.
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Peter Ellis

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Re: Latest PIOMAS update (December)
« Reply #469 on: December 17, 2014, 10:36:55 AM »
Most of those seem consistent with each other, the only one that's very different is the second quote which explicitly refers to October AND NOVEMBER, so it's not talking about the actual lowest point.

Table 1 in the Laxton document covers Oct/Nov AND is looking only at the ICESat domain to compare things to the previous satellite, so there's no reason to expect it to be simply comparable to the other figures.

diablobanquisa

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Re: Latest PIOMAS update (December)
« Reply #470 on: December 17, 2014, 01:18:58 PM »
Hi Peter,
-Which is the lowest year (October)? 2012? (BBC 2013) Or 2011? (BBC 2014)
-Which is the lowest October value? 6000 km3? (BBC 2013 and ESA 2013) Or 5300 km3? (BBC 2014)

I'd like to see a complete and consistent time series from 2010 to 2014. And I don't mind if it uses  'October', 'October/November' or 'October and November' data. I'm just asking for the same metric every year.
(Of course, if I could choose I'd prefer a consistent with Icesat metric )


« Last Edit: December 17, 2014, 01:33:55 PM by diablobanquisa »

ChrisReynolds

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Re: Latest PIOMAS update (December)
« Reply #471 on: December 17, 2014, 06:42:43 PM »
Hi Peter,
-Which is the lowest year (October)? 2012? (BBC 2013) Or 2011? (BBC 2014)
-Which is the lowest October value? 6000 km3? (BBC 2013 and ESA 2013) Or 5300 km3? (BBC 2014)

I'd like to see a complete and consistent time series from 2010 to 2014. And I don't mind if it uses  'October', 'October/November' or 'October and November' data. I'm just asking for the same metric every year.
(Of course, if I could choose I'd prefer a consistent with Icesat metric )

I agree. You shouldn't have to stop yourself and ask if the latest data is according to a different measure than the previous. And it would seem reasonable to allow easy comparison for the IceSat domain to be used for public data release.

I still consider that the best long term proxy for volume is PIOMAS, I will keep on using that in preference to IceSat.

viddaloo

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Re: Latest PIOMAS update (December)
« Reply #472 on: December 17, 2014, 07:05:52 PM »
Cryosat seems to be the only direct measurement of sea ice volume, so for sea ice volume purposes, I'd go for Cryosat, rather than PIOMAS or Icesat.
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ChrisReynolds

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Re: Latest PIOMAS update (December)
« Reply #473 on: December 17, 2014, 08:17:32 PM »
Cryosat seems to be the only direct measurement of sea ice volume, so for sea ice volume purposes, I'd go for Cryosat, rather than PIOMAS or Icesat.

ICESat ran back in the early 2000s, it used a LIDAR to measure sea ice free board. Ron Kwok at JPL had a series of papers looking at the results. It was a direct measurement of sea ice thickness. ICESat results were used in the calibration of PIOMAS.
http://scholar.google.co.uk/scholar?hl=en&q=kwok+icesat&btnG=&as_sdt=1%2C5&as_sdtp=

viddaloo

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Re: Latest PIOMAS update (December)
« Reply #474 on: December 17, 2014, 11:50:23 PM »
Radio EcoShock on the recent hacks against the NOAA computer systems: ES_141217_LoFi.mp3 (min. 14 onwards, if you are short on time)
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crandles

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Re: Latest PIOMAS update (December)
« Reply #475 on: December 18, 2014, 02:11:04 PM »
For Cryosat vs PIOMAS difference see Artic report card thread:

Quote from: Arctic report Card
Recent studies of the impact of snow layer properties on CryoSat-2 freeboard retrieval conclude that radar backscatter from the snow layer may lead to a bias in sea ice freeboard if it is not included in the retrieval process (Ricker et al. 2014, Kwok et al. 2014). Current sea-ice thickness data products from CryoSat-2 are, therefore, based on the assumption that the impact of the snow layer on radar freeboard is constant from year to year and snow depth can be sufficiently approximated by long-term observation values.
Perhaps ESA is suffering from the 'radar backscatter from the snow layer' issue?
« Last Edit: December 18, 2014, 04:31:20 PM by crandles »

ChrisReynolds

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Re: Latest PIOMAS update (December)
« Reply #476 on: December 18, 2014, 07:12:23 PM »
Thanks Crandles,

I've said before that this is a major reason to view Cryosat with caution.

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Re: Latest PIOMAS update (January)
« Reply #477 on: January 06, 2015, 01:02:25 PM »
The daily PIOMAS data is still not in, but gridded data is. From it we can estimate that in December the volume was 1654 km3 more than in 2013.  In November the difference was 1859 km3.

Here are thickness maps for December 2013 and 2014 as well as their difference.

Wipneus

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Re: Latest PIOMAS update (January)
« Reply #478 on: January 06, 2015, 01:04:13 PM »
And difference in growth from November to December, red means more thickening/less thinning.

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Re: Latest PIOMAS update (January)
« Reply #479 on: January 06, 2015, 05:38:17 PM »
I dumbed down the excellent graphic above to 3 color classes and took percent of pixels as an approximation to sq km of area, below.

Four papers at AGU mentioned PIOMAS in their abstract. None of these provided an ePoster:

C43B-0397 Estimation of Sea Ice Thickness through Maximum Covariance Analysis
https://agu.confex.com/agu/fm14/meetingapp.cgi#Paper/26406

C53A-0292 Arctic Ocean Sea Ice Thickness, Bathymetry, and Water Properties from Submarine Data
https://agu.confex.com/agu/fm14/meetingapp.cgi#Paper/18799

B41E-0103 Changing Seasonality of Tundra Vegetation and Associated Climatic Variables
https://agu.confex.com/agu/fm14/meetingapp.cgi#Paper/9002

C11A-0354 MIZMAS Forecast of Sea Ice Thickness and Drift in the Beaufort Sea Marginal Ice Zone
https://agu.confex.com/agu/fm14/meetingapp.cgi#Paper/31003

Eleven Arctic abstracts were accompanied by an ePoster: see screenshot below for titles.

https://agu.confex.com/data/handout/agu/fm14/Paper_26223_handout_790_0.pdf
https://agu.confex.com/data/handout/agu/fm14/Paper_3556_handout_319_0.pdf
https://agu.confex.com/data/handout/agu/fm14/Paper_7358_handout_773_0.pdf
https://agu.confex.com/data/handout/agu/fm14/Paper_10720_handout_301_0.pdf
https://agu.confex.com/data/handout/agu/fm14/Paper_16731_handout_1975_0.pdf
https://agu.confex.com/data/handout/agu/fm14/Paper_20721_handout_1782_0.pdf
https://agu.confex.com/data/handout/agu/fm14/Paper_21258_handout_1771_0.pdf
https://agu.confex.com/data/handout/agu/fm14/Paper_27927_handout_923_0.pdf
https://agu.confex.com/data/handout/agu/fm14/Paper_30369_handout_2045_0.pdf
https://agu.confex.com/data/handout/agu/fm14/Paper_30841_handout_1409_0.pdf
https://agu.confex.com/data/handout/agu/fm14/Paper_8127_handout_1971_0.pdf

Steven

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Re: Latest PIOMAS update (January)
« Reply #480 on: January 08, 2015, 11:26:02 PM »
Daily PIOMAS data for December 2014 now available:
http://psc.apl.uw.edu/research/projects/arctic-sea-ice-volume-anomaly



Currently 8th lowest on record.

Daily PIOMAS volume for December 31st, ranked:

1. 2012. 13.92 k km^3
2. 2010. 14.66
3. 2011. 15.01
4. 2013. 15.78
5. 2009. 15.95
6. 2007. 16.39
7. 2006. 16.55
8. 2014. 16.84   
9. 2008. 16.89
10. 2005. 17.72
...

Neven

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Re: Latest PIOMAS update (January)
« Reply #481 on: January 09, 2015, 12:22:51 AM »
Thanks, Steven. I'll have a blog post up on the ASIB tomorrow evening.
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Wipneus

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Re: Latest PIOMAS update (January)
« Reply #482 on: January 09, 2015, 06:00:55 AM »
Updated, graphs are in the top post.

(gridded data was already updated earlier this week, graphs above)

viddaloo

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Re: Latest PIOMAS update (January)
« Reply #483 on: January 10, 2015, 12:00:24 PM »
Updated collapse estimate. (chart faq)

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Gray-Wolf

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Re: Latest PIOMAS update (January)
« Reply #484 on: January 10, 2015, 12:26:53 PM »
So it appears the resumption in Fram exports has impacted, a little, the ranking and so I would expect this to be further 'impacted' in Jan's figure as the losses through Fram continue but also the 'normal gains' of Bering at this time of year fail to materialise?

This may be the second year in a row where we entered refreeze carrying a better load of ice only to see this decline ( in relative terms?) through Jan/Feb/March?
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ko.yaa.nis.katsi (from the Hopi language), n. 1. crazy life. 2. life in turmoil. 3. life disintegrating. 4. life out of balance. 5. a state of life that calls for another way of living.
 
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crandles

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Re: Latest PIOMAS update (January)
« Reply #485 on: January 10, 2015, 01:21:57 PM »
So it appears the resumption in Fram exports has impacted, a little, the ranking ...

Didn't the ranking change from 7th lowest at end of November to 8th lowest at end of December? ;)

Yes I would think most people would expect falls in ranking over the winter like 2014 and not necessarily due to Fram exports. I would suggest factors in order of importance:

1. The thicker the ice, the more slowly it grows thicker.
2. Fram export - speed and thickness seems high at least at present.
3. Low area in Bering - this might keep the volume down particularly in the near term and perhaps by continuing to keep extent down but maybe with less ice it can grow volume rapidly over late Jan Feb & Mar.

Gray-Wolf

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Re: Latest PIOMAS update (January)
« Reply #486 on: January 10, 2015, 08:05:26 PM »
Oopsie! my bad!!!
KOYAANISQATSI

ko.yaa.nis.katsi (from the Hopi language), n. 1. crazy life. 2. life in turmoil. 3. life disintegrating. 4. life out of balance. 5. a state of life that calls for another way of living.
 
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Re: Latest PIOMAS update (January)
« Reply #487 on: January 11, 2015, 06:55:15 AM »
So it appears the resumption in Fram exports has impacted, a little, the ranking and so I would expect this to be further 'impacted' in Jan's figure as the losses through Fram continue but also the 'normal gains' of Bering at this time of year fail to materialise?
Sea Surface temperatures in the Bering Sea have been at record warmth for the past 6 months according to NOAA, with  Jul - Nov all rated warmest and December rated second warmest.  I  doubt that we will see much ice at all there in the coming months. 
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viddaloo

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Re: Latest PIOMAS update (January)
« Reply #488 on: January 11, 2015, 10:10:19 AM »
With half the decade gone, only 4 months contribute to the collapse, while 8 months do their best to resist and compensate:



January packs 10% more volume in the 2010s than in the late 1900s.
February packs 14% more volume in the 2010s than in the late 1900s.
March packs 18% more volume in the 2010s than in the late 1900s.
April has 75% lower net refreeze volume in the 2010s than in the late 1900s.
May melts 92% more volume in the 2010s than in the late 1900s.
June melts 37% more volume in the 2010s than in the late 1900s.
July melts 14% less volume in the 2010s than in the late 1900s.
August melts 20% less volume in the 2010s than in the late 1900s.
September has 36% lower net refreeze volume in the 2010s than in the late 1900s.
October packs 17% more volume in the 2010s than in the late 1900s.
November packs 25% more volume in the 2010s than in the late 1900s.
December packs 12% more volume in the 2010s than in the late 1900s.
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Neven

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Re: Latest PIOMAS update (January)
« Reply #489 on: January 11, 2015, 11:04:09 AM »
Blog post is up on ASIB: PIOMAS update January 2015.
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crandles

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Re: Latest PIOMAS update (January)
« Reply #490 on: February 06, 2015, 12:13:16 AM »
Latest update 5th Feb 2015:

2015  31  20.229 very nearly 2500 km^3 more than record low
2014  31  18.935
2013  31  17.733 record low
2012  31  18.432
2011  31  17.938
2010  31  19.222
2009  31  20.397 higher than 2015
2008  31  20.210
2007  31  19.584
2006  31  20.834 higher than 2015

So 8th lowest since turn of century.

For comparison at 31 Dec record low is 31/12/12 13.921
31/12/14 was 16.845 2924 km^3 above record low.

So the gap above the record low has grown slightly from 2924 to 2996 km^3.
« Last Edit: February 06, 2015, 12:18:23 AM by crandles »

viddaloo

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Re: Latest PIOMAS update (February)
« Reply #491 on: February 06, 2015, 07:23:05 AM »
Code: [Select]
2015   1  16.927
2015   2  16.991
2015   3  17.065
2015   4  17.154
2015   5  17.247
2015   6  17.365
2015   7  17.472
2015   8  17.572
2015   9  17.655
2015  10  17.749
2015  11  17.854
2015  12  17.980
2015  13  18.113
2015  14  18.240
2015  15  18.360
2015  16  18.478
2015  17  18.593
2015  18  18.722
2015  19  18.839
2015  20  18.971
2015  21  19.095
2015  22  19.216
2015  23  19.331
2015  24  19.434
2015  25  19.540
2015  26  19.639
2015  27  19.756
2015  28  19.872
2015  29  19.981
2015  30  20.111
2015  31  20.229
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Wipneus

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Re: Latest PIOMAS update (February)
« Reply #492 on: February 06, 2015, 08:06:27 AM »
Updated, graphs are in the top post.

(gridded data updated also, I will post the graphs later)
« Last Edit: March 11, 2015, 06:44:31 PM by Wipneus »

Wipneus

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Re: Latest PIOMAS update (February)
« Reply #493 on: February 06, 2015, 10:28:49 AM »
Here are thickness maps for January 2014 and 2015 as well as their difference.

(total January volume is about 1000 km3 bigger than in 2014)

Wipneus

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Re: Latest PIOMAS update (February)
« Reply #494 on: February 06, 2015, 10:35:33 AM »
And difference in growth from December to January,  red means more thickening/less thinning.

(total growth was about 3.4 [1000 km3], slightly less than the 3.6 [1000 km3] a year ago)

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Re: Latest PIOMAS update (February)
« Reply #495 on: February 07, 2015, 07:21:19 AM »
It's all way too thin, especially considering the hot cyclones blowing up along the eastern seaboard dragging heat and moisture into the Greenland, Norwegian and Barents.

I'm pessimistic.
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Jim Hunt

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Re: Latest PIOMAS update (February)
« Reply #496 on: February 07, 2015, 11:27:55 AM »
It's all way too thin

Not forgetting that CryoSat 2 reckoned the ice was thinner in Oct/Nov 2014 than in 2013.

Quote
Measurements made during October and November show that the volume of Arctic sea ice now stands at about 10 200 cubic km – a small drop compared to last year’s 10 900 cubic km

(Click the image to see a 1.5 Mb animation)
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Neven

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Re: Latest PIOMAS update (February)
« Reply #497 on: February 07, 2015, 12:23:19 PM »
PIOMAS February 2015 over on the ASIB.
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Jim Hunt

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Re: Latest PIOMAS update (February)
« Reply #498 on: February 07, 2015, 12:26:03 PM »
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Neven

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Re: Latest PIOMAS update (February)
« Reply #499 on: February 07, 2015, 01:30:52 PM »
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