Yves Smith on the Fed's Choices
links for 2007-08-22

Chris Mooney: Hurricane Dean Is the Ninth Most Intense Atlantic Hurricane Ever Measured

Chris Mooney writes:

Hurricane Dean: 1 Of 10 Most Intense Atlantic Hurricanes Ever Measured: Early this morning Hurricane Dean... slammed the Yucatan Peninsula around Chetumal as a Category 5 hurricane with winds upwards of 165 miles per hour and a minimum central pressure of 906 millibars.... Its pressure was the ninth lowest ever measured in the Atlantic, and the third lowest at landfall. Indeed, there hasn’t been a full Category 5 landfall in our part of the world since 1992’s Hurricane Andrew. Dean was in all respects a terrifying storm, and we can only hope that the damage will somehow be less than expected as it tears across the peninsula and then, after crossing the Bay of Campeche, moves on to a presumed second Mexican landfall.

No one storm says anything about climate change; but... let’s consider the storm from a climate perspective, bearing in mind the scientific expectation that global warming ought to intensify the average hurricane (by how much remains hotly disputed). How does Dean fit into that ongoing scientific argument? Well, first of all, Dean now takes its rank among the top ten most intense Atlantic hurricanes. If you look at that list you’ll see that six of the strongest (Wilma, Rita, Katrina, Mitch, Dean, and Ivan) have been in the past ten years. That’s not the kind of statistic that’s easy to overlook. According to these data we are getting more super-strong storms in the Atlantic basin than we ever have before.

To be sure, there’s a counterargument here: Data wasn’t as good on hurricane intensity in previous eras as it is today, when our measuring equipment is better than ever. Stronger storms may well have existed in the past, but we were simply incapable of detecting their true strength.

This is a serious objection, although it’s hard to know precisely how serious. Nevertheless, the fact remains that if you look at the official records, Dean now fits in to a staggering hurricane decade. That’s highly suggestive, if not definitive. And this staggering decade has occurred in part because of anomalously warm ocean temperatures in the hurricane-prone regions. Many scientists question whether you can explain these warm anomalies without invoking global warming as at least part of the cause. So once again, even though Dean was not “caused” by global warming, when considered in its Atlantic context the storm is certainly consistent with the argument that there’s something going on out there that’s new — and more than a little scary...