Saturday, February 11, 2012

Climate betting update - back to where we started, and I'm not worried

Several weeks ago I received my annual friendly email from David Evans, my betting partner/opponent over future temperature increases, with the 2011 temp data from GISS.  Bet details are here, summary is that I've bet $9,000 and David $6,000 for a series of decade-plus bets over whether temps will increase somewhat near the IPCC projected rate or at a much lower rate.

David mentioned that the five-year average we're betting on is, for 2009, back to where we started in 2007, which would be very bad for my side of the bet, but he also politely added that we've had some La Ninas to affect things.  I'm not too worried for my pocketbook - the five year average for 2009 overlaps too much with 2007 to expect a lot of movement.  The five year average for 2012, which we won't know until 2015, will be the first that has no overlap.  First bets pay out or are voided in 2020, so as David says, this betting will take a while.

One way to look at it is to assume a counterfactual that the bet started in 1989 and ended in 2009 - fair from my viewpoint of expecting past rises to continue/accelerate, but not what David expects.  My calculation is that I win all three of the low end bets, void one of the high end bets, lose the other two high end bets, and come out ahead $1000.

Not much other activity from me on the climate betting front, and I haven't heard much from others either besides William's sea ice, unless I've missed it.  I've been thinking that sea level rise might be less noisy than temps, allowing shorter bet periods and maybe using three year averages.  Maybe will look into that later.

Last year's betting update here.