All In January 15, 2009Posted by honestclimate in Discussions.
Tags: climate change, global warming
From Prometheus, January 14, 2009
It is a bit early in the year to staking out a position in the race for boneheaded move of the year in the climate wars, but NASA GISS has done just that but doubling down on its prediction that 2009 or 2010 will be the warmest on record. One might think that the surprising 2008 global temperatures (i.e., surprising to folks making short-term predictions at least) would motivate some greater appreciation for uncertainty. Not so. Here is what NASA GISS says:
. . . in response to popular demand, we comment on the likelihood of a near-term global temperature record. Specifically, the question has been asked whether the relatively cool 2008 alters the expectation we expressed in last year’s summary that a new global record was likely within the next 2-3 years (now the next 1-2 years). . . Given our expectation of the next El Niño beginning in 2009 or 2010, it still seems likely that a new global temperature record will be set within the next 1-2 years, despite the moderate negative effect of the reduced solar irradiance.
Joe Romm takes the startling position that the fortunes of climate policy may well depend on how temperature evolves over that period:
for better or worse, what happens to temperatures in the next few years may well affect just how much climate action that we are going to take
Joe might ask why it is that short-term behavior of the climate system has political meaning. I have some ideas. Offering predictions of the evolution of global temperatures on timescales of years is foolish, (especially so when you also control the dataset used to evaluate the predictions). Explicitly associating the evoloution of temperatures with political outcomes on such a short timescale is also foolish.
Here are some tips for NASA GISS and advocates for action on carbon dioxide emissions:
1) Maybe we can predict the climate over timescales of one to two years, and maybe we can’t. Such forecasts should be viewed as highly experiemental, and the track record of such forecasts is not so good.
2) Accelerating decarbonization of the global economy makes good sense, regardless of the evolution of global temperatures over the next 1, 2 or 10 years. As my father and I wrote in 2006:
There is no greater danger to support for action on important issues of human impacts on the environment than an overselling of what climate science can provide. If the climate behaves in ways that are unexpected or surprising it will be more than just credibility that is lost. Advocates for action should think carefully when gambling with the unknown predictive abilities of climate models. The human influence on the climate system is real, but the climate may not always cooperate.