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Author Topic: CryoSat-2/SMOS Arctic Sea Ice Volume  (Read 1799 times)

Jim Hunt

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CryoSat-2/SMOS Arctic Sea Ice Volume
« on: February 06, 2020, 09:38:43 AM »
I'm not a Python expert, so thanks are due to both Wipneus and Stefan Hendricks for their contribution to the attached source code. Thanks also to Christian for the inspiration.

It converts the gridded merged CryoSat-2/SMOS Arctic sea ice volume data available from the Alfred Wegener Institute into numbers in a CSV file. Here's the data:

ftp://ftpsrv2.awi.de/sea_ice/product/cryosat2_smos/v202/nh/

Here's the AWI manual:

https://spaces.awi.de/display/CS2SMOS/CryoSat-SMOS+Merged+Sea+Ice+Thickness

Here's the source code (rename .txt to .py):
« Last Edit: February 06, 2020, 12:14:01 PM by Jim Hunt »
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Jim Hunt

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Re: CryoSat-2/SMOS Arctic Sea Ice Volume
« Reply #1 on: February 06, 2020, 12:04:55 PM »
Here is a rendering of the program's output created in Excel, together with the raw data in a CSV file.

Note that the most recent 2 weeks of data is "near real time". All the rest is "reanalysed".
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Jim Hunt

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Re: CryoSat-2/SMOS Arctic Sea Ice Volume
« Reply #2 on: February 12, 2020, 10:41:11 AM »
Note that Stefan Hendricks has flagged up an “issue” with the CryoSat-2 NRT data:

https://spaces.awi.de/display/SIRAL/2020/02/11/CryoSat-2+-+missing+NRT+data+in+baseline-D

The NRT Level-1 data to the CryoSat-2 sea ice product is missing several orbits, mostly in the Russian Arctic as can be seen in the figure below.


Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Jim Hunt

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Re: CryoSat-2/SMOS Arctic Sea Ice Volume
« Reply #3 on: February 19, 2020, 11:25:45 AM »
Another week's data, and the "blip" is gradually disappearing. NRT data starts on January 31st in this graph:
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

blumenkraft

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Re: CryoSat-2/SMOS Arctic Sea Ice Volume
« Reply #4 on: February 19, 2020, 11:45:36 AM »
Jim, i think you mentioned it before, but let me ask again, what's the dotted red line? 1SD?

Jim Hunt

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Re: CryoSat-2/SMOS Arctic Sea Ice Volume
« Reply #5 on: February 19, 2020, 06:10:27 PM »
What's the dotted red line?

It's the "uncertainty" numbers from the CS2 NetCDF gridded data. You'd need to ask Stefan precisely what it represents.
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

blumenkraft

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Re: CryoSat-2/SMOS Arctic Sea Ice Volume
« Reply #6 on: February 19, 2020, 06:15:15 PM »
Ah, it makes sense.

Thanks, Jim! :)

Jim Hunt

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Re: CryoSat-2/SMOS Arctic Sea Ice Volume
« Reply #7 on: August 09, 2020, 02:01:03 PM »
N.B. I have discovered another "issue" with the AWI merged CryoSat-2/SMOS data, confirmed by Stefan:

https://GreatWhiteCon.info/2020/07/the-northwest-passage-in-2020/#comment-343435

Quote
It looks as though in 2019 the merged product used CS2 data in the CAA, whereas in 2020 it doesn't?
Reality is merely an illusion, albeit a very persistent one - Albert Einstein