Climate researchers at Purdue University and the Massachusetts Institute of Technology separately reported new evidence yesterday supporting the idea that global warming is causing stronger hurricanes. That claim is the subject of a long-running scientific dispute. And while the new research supports one side, neither the authors nor other climate experts say it is conclusive.
In one new paper, to appear in a coming issue of Geophysical Research Letters, Matthew Huber of the Purdue department of earth and atmospheric sciences and Ryan L. Sriver, a graduate student there, calculate the total damage that could be caused by storms worldwide, using data normally applied to reconciling weather forecast models with observed weather events. The Purdue scientists found that their results matched earlier work by Kerry A. Emanuel, a hurricane expert at M.I.T. Dr. Emanuel has argued that global warming, specifically the warming of the tropical oceans, is already increasing the power expended by hurricanes. The approach used by the Purdue researchers, concentrating on what is called reanalysis data, has never been tried for this purpose before, Dr. Huber said in an interview, adding, "We were surprised that it did as well as it did."
In a statement accompanying the release of the study, Dr. Huber said the results were important because the overall measure of cyclone activity, whether through more intense storms or more frequent storms, had doubled with a one-quarter-degree increase in average global temperature.
In the other new study, Dr. Emanuel and Michael E. Mann, a meteorologist at Pennsylvania State University, compared records of global sea surface temperatures with those of the tropical Atlantic and said the recent strengthening of hurricanes was attributable largely to the rise in ocean surface temperature.
EDIT
http://www.nytimes.com/2006/05/31/science/31climate.html?_r=2&oref=slogin&oref=slogin