The Island of Doubt

Should scientists place bets on how well they can predict the future? I'm not talking about inter-lab wagers on the outcome of some arcane experiment. Such games are commonplace, and usually involve ersatz currencies such as beers or domestic services. But what about real money on something as consequential as a computer model of climate trends? Is that consistent with the professional detachment that's supposed to accompany honest research?

The Real Climateers argue that there are cases in which such bets can help explain the science, or at least, the degree of confidence that scientists hold in their work. The attention given a recent set of climate predictions published in none other than Nature is, they say, just such a case.

The Nature study, by Keenlyside et al. involved a set of decade-long temperature averages that suggest the 2005-2015 interval will experience "a slight cooling relative to 1994-2004 conditions." This, of course, got lots of play in climate denial circles, most outlets of which completely missed the central point that Keenlyside and his co-authors in no way challenge the anthropogenic global warming consensus. In fact, their calculations, which focused on the on the Northern Atlantic region, showed a resumption of relatively rapid warming by the 2020s.

I wrote about how easy it is to corrupt the findings of such a study a couple of weeks ago, and Joe Romm did a marvelous job of picking apart just what it was that Keenlyside et al were trying to do.

Neither I nor Joe are in a position to take issue with the paper's science. We both noted, however, that this isn't the first time reputable scientists have predicted cooling in the near future. Smith et al in Science last year call for a very brief period of non-warming ending in 2009, for example.

The Real Climate gang are better poised to judge the science, and they found the Keenlyside predictions wanting for a variety of reasons, including the failure of the new study's hindcasting to accurately replicate actual temperature trends in the 1970s and 1990s. So sure are RC guys that Keenlyside's group is wrong that they are willing to put their money where there mouths are:

If the average temperature 2000-2010 (their first forecast) really turns out to be lower or equal to the average temperature 1994-2004, we will pay them 2500 euros. If it turns out to be warmer, they pay us 2500 euros. This bet will be decided by the end of 2010.

Over at Andy Revkin's NY Times' Dot Earth blog, numerous comments to his post on the wager pointed out various problems with this sort of thing. But others welcomed the development. And there is some precedent. James Annan made a similar bet with a pair of Russians in 2005. And our own William "Stoat" Connelly has even put up $100 that the RC bet won't be accepted.

The RC gang argue that debating the science isn't enough. So successful have the pseudoskeptics been at exaggerating the uncertainty of climate modeling that far too many news consumers just don't have any idea just how confident most climatologists are about the consensus. So what we need is a gimmick that people understand. And a consequential bet just might do the trick:

Why did we propose a bet on this forecast? Mainly because we were concerned by the global media coverage which made it appear as if a coming pause in global warming was almost a given fact, rather than an experimental forecast. This could backfire against the whole climate science community if the forecast turns out to be wrong.... If different groups of scientists have a public bet running on this, this will signal to the public that this forecast is not a widely supported consensus of the climate science community, in contrast to the IPCC reports (about which we are in complete agreement with Keenlyside and his colleagues)....

By ignoring the AGW consensus and the advice climatologists are giving society on the need to radically reduce fossil-fuel emissions, we are, in effect, gambling on the future. We're saying that we are prepared to bet the fate of civilization on the entire climatology community being wrong. It's hard to put a specific value on that bet, but it's pretty large.

If we win, we've saved a few hundred billion dollars we might have spend on renewable and clean energy. If we lose, our losses will be unprecedented and near incalculable. That doesn't seem too wise to me.

By comparison, the RC gang are prepared to put their scientific reputations on the line that the climate science community knows what its talking about.

I know who I'm betting on.