JAXA AMSR-E Sea Ice Extent -15% or greater – click to enlarge
I submitted the WUWT ARCUS sea ice forecast today, based on votes received in our poll.
Here is what I submitted via email, and asked for an acknowledgment:
PAN-ARCTIC OUTLOOK – WUWT (acronym for WattsUpWithThat.com)
- Extent Projection: 5.5 million square kilometers
- Methods/Techniques: web poll of readers
- Rationale: Composite of projections by readers, projection bracket with the highest response is the one submitted.
- Executive Summary: Website devoted to climate and weather polled its readers for the best estimate of 2011 sea ice extent minimum by choosing bracketed values from a web poll which can be seen at: http://wattsupwiththat.com/2011/05/19/sea-ice-news-call-for-arctic-sea-ice-forecasts-plus-forecast-poll/15.64% chose 5.5 million km2 or greater, with 13.09% choosing 5.0 to 5.1 million sq km2 as the second highest vote.
- Estimate of Forecast Skill: none
Outlook submission deadline: Tuesday, 31 May 2011. All Outlooks should be sent to: Helen Wiggins, ARCUS Email: helen@arcus.org
submitted by Anthony Watts
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My choice for my own personal vote was 4.9 to 5.0 million square kilometers.
Tim Folkerts – “A weighted average could be done.. 5.17 for the weighted average”
Bravo sir! I was about to do the same calculation. I think this is a better reflection of the result of the poll.
If we compare to, for example, tamino’s forecast of 4.63 +/- 0.9, then it lies well in the upper quartile of tamino’s forecast [assuming a uniform distribution], or above one standard deviation of his forecast [assuming a normal distribution with error bars given for a 90% confidence interval].
To make the above paragraph a bit clearer, I think tamino’s forecast implies an 84% probability of less than 5.17 million km^2 and roughly 95% probability of less than 5.5 million km^2.
So there’s a real divergence of opinion here, to be tested by this season’s data.
That said, Mr Watts has submitted the figure of “5.5”, rather than “greater than 5.5”, so he’s not simply taken the mode result either.
With the fast early pace for reduction of Sea Ice currently underway, we could easily beat the low of 2007 although I would guess we will finish very slightly ahead of that record low. With his prediction of a modest increase for 2011 in Arctic ice at the lowest point on record, I fear Joe Bastardi will miss the mark this year.