The summary of betting on sea ice refers. If you look in my comments, you’ll find any number of well intentioned people advising me that its time to close up the bets before I take a bath. But I haven’t. Anyone wanting to pile in is still welcome (if you can’t be bothered to look up the previous post the bet is simple: will this years Arctic sea ice extent minimum, as measured by the satellites, be less than last year? I say no).
The May 5th version of “Arctic sea ice news and analysis” provides some more fodder. I’ve ripped off a pic from them which I like. To me, it rather suggests no record this year. They somehow convince themselves that it does suggest a min. Hey ho, we’ll find out in a few months. Their section on “Estimating September extent based on past conditions” is cute. I like it; its a nice idea. Totally lacking, of course, is how would this idae have fared if applied last year, or the year before, or…
My personal opinion remains that we simply can’t forecast year-to-year variations with any degree of reliability. The long-term trend is clearly downwards, and there will be a new record sometime. But based purely on the behaviour of the sea-ice extent timeseries I still consider that new record this year is less than 50% likely. I also wonder if people aren’t in some danger of getting a teensy bit carried away publishing these “forecasts” which they don’t really believe. They are speculative prognosticaions, no more.
Andy Revkin (its him again!) covers this. In the comments, Bill Chapman is reported to say “I say the odds favor a new NH record minimum – put my money there.” I’ve replied (#40) but haven’t heard from him… I must give him an email. [update: I did. He declined -W]
[Update: via Gareth I discover this rather useful picture, which puts the present year more into context. It gives me hope for my bet. So, if you’re still interested… -W]