Geophys. Res. Lett. 34, L08702 (2007)

Credit: NASA

An increase in the intensity of Atlantic hurricanes over the past decade has been attributed to climate change. Now, a new study suggests that global warming could induce atmospheric changes that will tear apart Atlantic hurricanes during this century.

Using 18 of the latest global climate models, Gabriel Vecchi at the National Oceanic and Atmospheric Administration in Princeton, New Jersey and Brian J. Soden from the University of Miami in Florida predicted the number and intensity of tropical Atlantic storms for early and late twenty-first century. Wind shear, caused by differences in the speed or direction of wind with altitude, is likely to strengthen in the region, they found. This effect is linked to weakening of the Pacific Walker circulation, a wind system that influences global climate and slows during El Niño events when fewer hurricanes form.

The study represents the first evidence that changes in wind shear could be large enough to counteract the increase in hurricane activity associated with higher sea surface temperatures. In the tropical Atlantic and East Pacific, the effect of wind shear on hurricanes could overpower that of ocean warming. Most other areas, however, will experience more frequent and intense storms.