Bad Blow

Hurricanes and global warming

Hurricane Katrina's "real name is global warming," the environmentalist Ross Gelbspan wrote in The Boston Globe in 2005. Gelbspan's comment reflected the speculations of several climatologists who believe global warming is making hurricanes more frequent and fiercer.

The World Meteorological Organization isn't so sure. In December the group issued a consensus statement by 125 of the globe's leading hurricane researchers that says a link between manmade global warming and more hurricanes has yet to be demonstrated. "Though there is evidence both for and against the existence of a detectable anthropogenic signal in the tropical cyclone climate record to date," the statement says, "no firm conclusion can be made on this point."

What about the claim that hurricanes are becoming stronger? "This is a hotly debated area for which we can provide no definitive conclusion," the researchers say. They do note that higher sea surface temperatures fuel hurricane winds, and that climate models project hurricane wind speeds will increase 3 percent to 5 percent for every 1 degree Celsius increase in temperature.

If it cannot be said for certain that hurricanes are becoming more numerous and powerful, why did coastal areas experience so much damage in 2004 and 2005? The researchers blame it on the fact that a lot more people are living and working in more buildings near the Atlantic and Gulf coasts.