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Author Topic: Sea Ice Thickness from CryoSat-2  (Read 6185 times)

Vergent

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Sea Ice Thickness from CryoSat-2
« on: August 05, 2013, 02:37:05 AM »
Well, this came out almost a month ago, no one on this forum spotted it(including me). Well beter late than never.

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CDAQFjAA&url=http%3A%2F%2Fwww.arcus.org%2Ffiles%2Fsearch%2Fsea-ice-outlook%2F2013%2F07%2Fpdf%2Fregional%2Fkaleschke_rickert.pdf&ei=M-f-UeyFGe_EiwLo6YCQBQ&usg=AFQjCNGFvdprpuMH8fHMx5gdnXGRlFT45A&sig2=n-eg6abRF_qLcBja2an58g

Here is a link to the pdf download.



2013



2012



2013-2012



Thickness distribution and mean thickness. It seems that PIOMAS failed to track the continued thickness and volume loss. Well, input starved models can go walkabout.

Quote
The trend of mean ice thickness is about -7 cm/yr.

-0.00007 km X 13,700,674 km^2 = -959 km^3

Vergent
« Last Edit: August 05, 2013, 04:24:14 AM by Vergent »

Jim Hunt

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Re: Sea Ice Thickness from CryoSat-2
« Reply #1 on: August 05, 2013, 03:41:46 AM »
Well, this came out almost a month ago, no one on this forum spotted it(including me).

It didn't go completely unremarked Vergent. See for example:

http://forum.arctic-sea-ice.net/index.php/topic,382.msg10329.html#msg10329

and

http://forum.arctic-sea-ice.net/index.php/topic,92.msg10445.html#msg10445
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Vergent

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Re: Sea Ice Thickness from CryoSat-2
« Reply #2 on: August 05, 2013, 04:23:30 AM »
Jim,

I did a forum search for "cryosat" Those two did not show up. One because it does not mention Cryosat, the other because of the hyphen. The concentration map, the concentration distribution graphic, and report itself have not been discussed or linked to that I was aware of.

Vergent

ChrisReynolds

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Re: Sea Ice Thickness from CryoSat-2
« Reply #3 on: August 05, 2013, 07:54:05 AM »
It seems that PIOMAS failed to track the continued thickness and volume loss. Well, input starved models can go walkabout.


Er, no PIOMAS didn't.


PIOMAS showed the decline in thickness profile in 2013.

March - volume contributions to thickness from various thickness bands of ice (bands in metres on lowest row).



EDIT - replaced May difference with March difference map.
« Last Edit: August 05, 2013, 08:04:37 AM by ChrisReynolds »

Vergent

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Re: Sea Ice Thickness from CryoSat-2
« Reply #4 on: August 05, 2013, 04:42:50 PM »
Chris,



In both thickness and volume PIOMAS showed a spring 2013 recovery to 2012 levels. While your data shows a decline in the median ice thickness, I think you will find that the mean did not decline(otherwise the PIOMAS reported volume would have declined, it did not). This is because PIOMAS overestimates thin ice thickness.

V

ChrisReynolds

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Re: Sea Ice Thickness from CryoSat-2
« Reply #5 on: August 05, 2013, 05:58:37 PM »
Yes, the total volume, and average thickness were at 2012 levels. But the gridded data shows that there was a marginal shift in the thickness profile downwards.

As it's turned out the weather has intervened and we haven't got to see the impact of that.  :(

crandles

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Re: Sea Ice Thickness from CryoSat-2
« Reply #6 on: August 06, 2013, 02:33:54 PM »
Yes, the total volume, and average thickness were at 2012 levels. But the gridded data shows that there was a marginal shift in the thickness profile downwards.

Surely there was a shift from both thin and thick categories towards more ice 0.6 to 1.8m thick?

TeaPotty

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Re: Sea Ice Thickness from CryoSat-2
« Reply #7 on: August 06, 2013, 04:10:23 PM »
Hey, I'm just an amateur scientist reading and learning from the terrific discussions here.

How reliable are these Navy maps?




ChrisReynolds

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Re: Sea Ice Thickness from CryoSat-2
« Reply #8 on: August 06, 2013, 06:34:11 PM »
Yes, the total volume, and average thickness were at 2012 levels. But the gridded data shows that there was a marginal shift in the thickness profile downwards.

Surely there was a shift from both thin and thick categories towards more ice 0.6 to 1.8m thick?

Aren't you describing the same thing? The data are visible up thread for people to make their own decision.

We don't seem to have heard from you for a while, good to 'see' you again.

ChrisReynolds

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Re: Sea Ice Thickness from CryoSat-2
« Reply #9 on: August 06, 2013, 06:36:40 PM »
Tea Potty,

Many of us have doubts about thickness, it often seems to be overstated which may be because the model is biased towards shipping safety. For myself it seems in the right ball-park right now. Over winter it was in line with PIOMAS and theory showing the new ice grown after last years record melt being around 2m thick.