Did Global Warming Boost Katrina's Fury?

Sept. 14, 2005 — -- If Katrina had struck the Gulf Coast just three decades earlier, the results might have been quite different.

It would have still been fierce, to be sure, but perhaps not quite as deadly as it was in the summer of 2005.

Researchers have found that if Katrina had hit in the early 1970s it would have had less moisture to fuel its powerful storm system, and less rain. That would have meant less water to pummel an outdated system of levees, and possibly, fewer failures.

And the finger of blame points quite clearly at global warming.

Global warming didn't create Katrina. But research indicates it enhanced it.

"Our estimate is that rainfall from Katrina was about 7 percent enhanced by global warming," says Kevin Trenberth, head of the climate analysis section of the National Center for Atmospheric Research in Boulder, Colo.

Trenberth's research is augmented by the work of a number of other scientists who are finding evidence that the greenhouse effect, produced primarily by the burning of fossil fuels, is boosting the power of great storms to an alarming degree. Kerry Emanuel, a leading hurricane expert at the Massachusetts Institute of Technology, believes major storms have increased in intensity and duration by a whopping 50 percent just since the 1970s.

Other research that reaches similar conclusions will be published shortly.

So scientists who have been saying that we won't see much effect from global warming for at least 50 years may be wrong. We may have seen a preview of what's to come when Katrina slammed into the mouth of the Mississippi.