As a result of my post yesterday (A Turning Point for the IPCC…and Humanity?), I became aware of a pending bet between Pat Michaels and Scott Supak (a self described progressive environmentalist) regarding the future course of global temperatures.

After exchanging e-mails with both Pat and Scott, you can consider this post as the official announcement of the bet:

Dr. Michaels is betting on no statistically significant warming (at the 95% confidence level) in the HadCRUTx data for the 25 year period starting in 1997. Scott is betting on at least that much warming.

Scott doesn’t want to bet more than $250 (he says he likes to spread his betting $$ around), so the potential value of the embarrassment to the loser is probably worth much more than $250 will buy in early 2022. 😉

I find this a rather bold bet for Pat to make, because based upon my calculations he could still lose and have the observed warming trend below ALL 90 of the CMIP5 climate model forecasts we have examined for global average surface temperature for the period 1997 through 2021, inclusive. [The model with the least warming of the 90 during 1997-2021 has only +0.048 deg. C/decade warming; current HadCRUT4 observations since 1997 stands at just over +0.04 deg. C/decade; max model warming is +0.400 deg. C/decade.] But maybe Pat has a better method of computing the statistical significance than I do…I’ll let Pat and Scott work that out.

I just noticed that the range of model trends ALSO means that ALL of the 90 models predict that warming will accelerate from the currently observed warming trend since 1997.

I’m also in discussions with Scott over betting on a trend that would be 1 standard deviation below the average model warming, which would be +0.162 deg. C/decade for 1997-2021, compared to the 90-model average of +0.226 deg. C/decade. He laid down the gauntlet, not me. I try not to forecast future temperatures…too much like betting on a roll of the dice.

If Pat wins, Scott will pay $250 to the Organization for Autism Research. If Scott wins, Pat will pay $250 to the Climate Science Legal Defense Fund.