Monday, April 24, 2006

Atlantic hurricanes and global warming

The power of Atlantic tropical cyclones has risen rather dramatically and the increase is correlated with an increase in the late summer/early fall sea-surface temperature over the North Atlantic. A debate concerns the nature of these increases with some studies attributing them to a natural climate fluctuation, known as the Atlantic Multidecadal Oscillation (AMO), and others suggesting climate change related in part to anthropogenic increases in radiative forcing from greenhouse-gases. Here I apply tests for causality using the global mean near-surface air temperature (GT) and Atlantic sea-surface temperature (SST) records during the Atlantic hurricane season and find that GT is useful in predicting Atlantic SST, but not the other way around. Thus I concluded that GT "causes" SST providing evidence in support of the climate change hypothesis.