The Dry Future

The WaPo has an article Looking at the current drought and wondering/speculating what will happen if and when such droughts become more common due to global warming.

A lot of the hype for this is keying off a study that claims Texas’ 2011 drought was twenty times more likely because of global warming. This study has been loudly trumpeted around the punditsphere but needs to be taken with several helpings of salt water. The analysis is based on climactic modeling, a notoriously tricky discipline. It wouldn’t take much to make the 20 times go down a lot. Second, the 2011 Texas drought was an extreme event, on the tail of the probability distribution. If you shift the probability distribution just a little bit, the probability of an unlikely even shoots up dramatically. For example, if the likelihood of an event happening was one in a million and your analysis made it one in fifty thousand, that would be “20 times more likely”. But it is still an unlikely event and still at point where small assumptions can dramatically alter the results. Looking at their plots, 2011 was still an outlier. While there’s a great deal of research supporting the idea that global warming will produce a drier world (or at leas a drier USA), it’s sketchy to build policy on it.

More importantly, the warming is inevitable. Even if we accept the current models; even we stopped all greenhouse gas emission today; the planet would continue to warm for another half century. We are long past the point of prevention; we are now at the point of adaptation, something the WaPo article only brushes against.

There is hope in adaptation. The current drought has been more extensive than past droughts that caused food shortages and famine. But drought-resistant crops and better land management have prevented the catastrophe of the Dust Bowl. We have not even begun to tap the potential for adaptation. And it’s a potential we’re going to have to tap if the next century is to be as plentiful as the last.