Someone Open the Window, it's Getting Warm in Here

Nick Kristof uses Hurricane Katrina as a springboard for a climate change discussion today.

Kristof acknowledges that it is unknown whether global warming contributed to Katrina’s existence or ferocity, but observes that there are indications that climate change will produce more Category 5 storms.

Accordingly, he says, “[n]ow that we've all seen what a Katrina can do - and Katrina was only Category 4 when it hit Louisiana - it would be crazy for President Bush to continue to refuse to develop a national policy on greenhouse gases.”

As an aside, let me first say, Mr. Kristof, that I won't be holding my breath that President Bush will do something because it would be "crazy" not to (See FEMA, failure to appoint competent people to).

But I digress, sort of. The real matter of interest is this interplay between hurricanes and climate change.

The eggheads at realclimate.org frame the relevant question:

Due to [the] semi-random nature of weather, it is wrong to blame any one event such as Katrina specifically on global warming - and of course it is just as indefensible to blame Katrina on a long-term natural cycle in the climate.

Yet this is not the right way to frame the question. As we have also pointed out in previous posts, we can indeed draw some important conclusions about the links between hurricane activity and global warming in a statistical sense.

The situation is analogous to rolling loaded dice: one could, if one was so inclined, construct a set of dice where sixes occur twice as often as normal. But if you were to roll a six using these dice, you could not blame it specifically on the fact that the dice had been loaded. Half of the sixes would have occurred anyway, even with normal dice. Loading the dice simply doubled the odds. In the same manner, while we cannot draw firm conclusions about one single hurricane, we can draw some conclusions about hurricanes more generally. In particular, the available scientific evidence indicates that it is likely that global warming will make - and possibly already is making - those hurricanes that form more destructive than they otherwise would have been.

It's a fascinating blog, if extremely technical. Head on over if you want to have the bejesus scared out of you in that cold, clinical way that only hardcore scientists can manage.