Arctic Sea ice volume tracker
There's a conflict in the comments with another model. G. Karst asks:
"And yet the US Navy, who actually went out and performed measurements, reports a 25% increase in Arctic ice volume since May 2008. Oh well, when empirical evidence contradicts models, Brett recommends modeled results. It could be that he is privy to information the rest of us, are not."
This is quoting a Watts Up with That? article, Arctic Ice Volume Has Increased 25% Since May, 2008 The model discussed in this article is the PIPS2.0 sea ice forecast model.
In the discussion section of the above article, poster "Tom P." says:
Steve,
Your approach does not agree with the calculations from the the team actually producing these maps. The Navy PIPS team derive a loss in the May ice volume from 2007 to 2008 of 22%.
http://www.nrl.navy.mil/content_images/09_Ocean_Posey.pdf
Your figures give a corresponding loss of around 13%. You might want to contact the PIPS team to see how they derive their volume estimates and hence understand how best to use this data.
I grabbed this table out of the above PDF. Spacing formatting wasn't transferred, but it isn't hard to figure out what it's showing. The maximum volume and the month it occurred are on the left, and the minimum volume and the month it occurred are on the right.
Total Central Arctic Ice Volume × 109 m3
Maximum Minimum
Year Month Value Month Value
2000 May 0.90 Sep 0.59
2001 May 0.93 Sep 0.69
2002 May 0.99 Sep 0.75
2003 Apr 0.95 Sep 0.58
2004 May 0.91 Sep 0.58
2005 Apr 0.93 Sep 0.62
2006 May 0.85 Sep 0.52
2007 May 0.86 Sep 0.49
2008 Mar 0.67 Sep 0.38
There are obvious declining trends here. But the Watts Up with That? article was about May 2008 to present, not 2000-2008. Is that significant? The author of the WUTW piece noted the same thing.
But further down, "R. Gates" says:
"An excellent presentation, and if the PIPS 2.0 data had any validity or accuracy I would almost believe it. Unfortunately, PIPS 2.0 was quite inaccurate with low fidelity and is no longer used by the Navy for any serious applications, and especially not to navigate their way through the Arctic."
and also says
"In general though, a nicely done effort, but I think your data is suspect, and I think you should realize that the modeling done by PIOMAS [the model quoted in the Accuweather article] is much closer to the more updated PIPS 3.0, as they both use CICE from Los Alamos, and thus, I would tend to stick to the projections of PIOMAS and the volume loss anomlay they project for the arctic over software that the Navy abandoned many years ago in PIPS 2.0"
Ouch. R. Gates answers some of the author's questions further down politely, but he and Tom P. together pretty much trashed this WUTW production. Though at the end there is a very interesting comeback from "KD Knoebel". I'll be interested to see if R. Gates responds. Because I want to know what's actually happening, even though I think I know what is most likely to be happening.
As for the funniest comment, this was, from "Tom in Florida":
"It’s never been about length, always about thickness."
Gave me a grin.
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After writing the above, I noticed that Joe Romm has done a much better job:
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