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Because of the El Nino and La Nina effects, and all those other factors, figuring out what might happen to hurricanes in a warmer world is, well, complicated. "Anything that does happen will likely cause only small changes," says Gray. "And no one can say which way these changes will go." If global warming favors more El Nino and fewer La Nina events, for instance, then the distribution of hurricanes will undoubtedly shift. But while there will be more typhoons in the Pacific and fewer hurricanes in the Atlantic, the total number of major storms is likely to remain the same. Worldwide, scientists think, there will probably continue to be about 80 such events in any given year.

How strong will those storms be? That's harder to estimate, in part because a very big storm is in some ways its own worst enemy. "A hurricane has a noticeable cooling effect on the ocean," explains atmospheric scientist Kevin Trenberth of the National Center for Atmospheric Research (NCAR). Indeed, at a certain stage of its life cycle, a storm of a given size will stir up enough cold water to put a halt to its growth. At that point, scientists say, it has come into equilibrium. Maintaining that balance is especially hard, because if a hurricane stirs up too much cold water, it will weaken and die. This suicidal tendency no doubt helps account for the fact that Category 5 hurricanes are so rare. Indeed, only two have hit the U.S. during this century, among them the 1969 hurricane named Camille.

How was it that Camille managed to grow so powerful? One reason, says Emanuel, is the path that Camille chose. She (in those days all hurricanes were of the feminine persuasion) faithfully followed the meanderings of the "loop current," a tributary of the Gulf Stream. It wasn't that the loop current was any warmer than the surrounding water at the surface, notes Emanuel, but its warmth went much deeper. Result: Camille's winds stirred up warm water as opposed to cold, and thus retained their strength.

Suppose, for the sake of argument, that global warming does cause the intensity of hurricanes to increase to supercane proportions. How stable would such megastorms be? A hurricane packing 200-m.p.h. winds would be significantly more powerful than Camille, whose top sustained winds were in the 180-m.p.h. range. Such a supercane would be capable, certainly, of taking a catastrophic toll, but its winds would also presumably penetrate to greater depths. Long before making landfall, a supercane might stir up a lethal dose of chilly water. More intense storms, in other words, could prove to be exceedingly fragile entities.

Of course, there are other ways in which global warming might boost the power of hurricanes. It's possible, for instance, that in a warmer world hurricanes might tank up with a lot more rain, which would greatly increase the damage caused by flooding. In addition, storm surges could be expected to become a lot more lethal if, as many anticipate, global sea levels rise.

But as NCAR's Roger Pielke Jr. observes, it's really not necessary to concoct ways to make hurricanes any more threatening than they already are. With or without global warming, there are going to be some whoppers in our future, and unlike Floyd, many of these will prove to be megadisasters. For the days when a big hurricane could make landfall in sparsely populated places are fast disappearing, Pielke notes, and that alone is cause enough for worry.