More Violent Hurricanes?

Add one more environmental disaster to the list of potential dire consequences of the greenhouse effect. A general warming of the earth because of increasing amounts of carbon dioxide and other gases in the atmosphere might not only melt the polar ice caps and drastically alter weather patterns but cause more ferocious storms. Writing in Nature, M.I.T. Meteorologist Kerry Emanuel warned that a warmer climate could result in hurricanes packing up to 50% more destructive power. This could happen, he suggests, within 40 to 80 years, when some scientists think CO2 levels will have doubled and ocean temperatures will have increased by 2 degrees C to 3 degrees C. Because the energy of warm, rising air is the driving force behind hurricanes, a warmer ocean would translate into stronger storms.

"What is very speculative at this point," Emanuel says, "is how the earth's climate will respond." One variable that could offset the rise in CO2 levels, for example, would be a change in cloud cover, which would cut down on the sunlight reaching the surface of the earth. Although it is too early to sound alarms, says Emanuel, his purpose is to make it clear "the consequences of the changes that are occurring are quite severe."