Global Warming NOT Featured in New Hurricane Study

The latest Science magazine features a paper linking increasing sea-surface temperatures to global increases in the most severe hurricanes, but it does NOT mention global warming as the cause. Think the newspapers won't?

Over the last few decades, hurricane climate experts have largely eschewed linkages between global warming and increases in the number or strength of hurricanes. That is, until late last summer, when a series of highly publicized papers claimed otherwise. The papers pointed out that sea-surface temperatures (SSTs), the essential fuel of hurricanes, have been increasing in the primary hurricane-development regions pretty much globally since 1970 (the start of global satellite hurricane track and intensity records). Over that time, hurricane intensities have also been on the rise. And since global warming causes SSTs to rise, that must be the cause of the recent spate of strong hurricanes.

The problem with this logic is that hurricanes require a very specific environment to flourish. High SSTs are a necessary but not sufficient condition to spin up strong storms. It is also important that there be very little change in the winds with height; that near surface winds blow in such a manner to cause moist air to gather near the storm's center; and that temperatures decline rapidly with height to promote a very unstable atmosphere, among other factors. One criticism of the studies from last summer is that the focus was almost entirely on SSTs only. In order properly to link hurricane trends to SSTs (and global warming), you need to discount trends in these other, critical variables.

A major hurricane is a very unique event — a lot of disparate factors must become organized in just the right way to allow a major storm to develop. While high SSTs are one critical ingredient, they alone are insufficient to generate a whopper storm. SSTs have been increasing since 1970, as have major hurricanes, but the connection is not nearly as simple as some authors are suggesting. And careful scrutiny of ALL of the available data shows the connection to global warming is less than tenuous. Details.