Bull. Am. Meteorol. Soc. doi:10.1175/BAMS-89-3-347 (2008)

Credit: NASA

A new modeling technique devised by atmospheric scientist Kerry Emanuel of the Massachusetts Institute of Technology and colleagues indicates that if the planet continues to warm, hurricane frequency will go down globally, although storms are projected to become more intense in some locations.

Climate models are complex beasts and are not geared to predict something as small as the birth of a hurricane, so Emanuel's team took a creative approach by seeding large, low-resolution climate models with the detailed physics of hurricanes. This 'mash-up' allowed them to run thousands of synthetic storms within the models, enough to make credible estimates of hurricane activity. The technique proved accurate when tested on climate data during 1986–2006, and when used to project future trends, it estimated an overall decrease in global storm activity between now and the period 2181–2200.

The projected increases in storm power are, surprisingly, more modest than the increases witnessed in the past 25 years, suggesting either that the recent changes are not largely driven by global warming or that the climate models suffer some systematic deficiency. Though Emanuel warns the results are preliminary, he says the uncertainties should fade away as global models improve.