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Author Topic: PIOMAS forecast: how reliable?  (Read 2954 times)

Nightvid Cole

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PIOMAS forecast: how reliable?
« on: June 22, 2013, 02:39:40 AM »
PIOMAS initialized on June 1 predicts a very strange spatial distribution of ice in September:

http://www.arcus.org/files/search/sea-ice-outlook/2013/06/pdf/pan-arctic/zhang_lindsay.pdf

with a piece of ice against the Siberian coast failing to melt at all. This hasn't happened since what, 1998?

I am highly skeptical...

TerryM

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Re: PIOMAS forecast: how reliable?
« Reply #1 on: June 22, 2013, 05:09:56 AM »
Their prediction of the NWP not being open through September indicates that they don't expect the CAA to be gobbling ice as it did last year. If they're right about that we won't come close to 2012's record. The problem I'm having with making any prediction this year is the huge uncertainty with regards to the CAA. I think if it acts as it did last year we're looking at a new record, but if the MYI blocks the passages it's back to square one.
Terry

sofouuk

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Re: PIOMAS forecast: how reliable?
« Reply #2 on: June 22, 2013, 07:30:55 AM »
I wouldn't pay too much attention to the ice against the Siberian coast - it's thin, covers a relatively small area, and they don't refer to it in the text. Probably best interpreted to mean there will still be some isolated bits in the east Siberian sea which don't have time to melt? Other than that the final pack looks about right, with a thin strip of thicker ice against Greenland/Canada and not much else. It will be wrong, of course, but it won't be very wrong

ChrisReynolds

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Re: PIOMAS forecast: how reliable?
« Reply #3 on: June 22, 2013, 07:32:59 AM »
It's too early to say how reliable it will be.

The area of ice off Siberia is similar to last year's August low concentration region. I've put that down to the presence of MYI in that region, if such a low concentration region happens again this year then I'll be ditching that explanation.

ChrisReynolds

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Re: PIOMAS forecast: how reliable?
« Reply #4 on: June 22, 2013, 07:42:25 AM »
Just thought, best to put this in context, extent minima (NSIDC):

    2005: 5.57
    2006: 5.92
    2007: 4.30
    2008: 4.73
    2009: 5.39
    2010: 4.93
    2011: 4.63
    2012: 3.61

PIOMAS prediction: 4.3 +/- 0.8M km^2. That's from 3.5 to 5.1. PIOMAS 2012 June prediction was 4.4 +/-0.5.

« Last Edit: June 22, 2013, 07:59:38 AM by ChrisReynolds »