STORM WARNING

Global warming brings stormy weather.

The global-warming phenomenon just keeps coming up with one surprise after
another. Researchers have already warned that it will probably create higher
tides, flooding coastal areas. Now, scientists at Woods Hole Oceanographic
Institution predict that warmer ocean temperatures may dramatically increase the
number and severity of hurricanes and typhoons that hit coastal cities in North
America and the Far East.

Hurricanes begin as unstable weather systems in the eastern portion of the
mid-Atlantic Ocean and intensify as they move west toward the Gulf of Mexico.
(Typhoons begin in the eastern Pacific Ocean and move toward the China seas.)
Warm pools of tropical ocean water fuel the escalating storms, creating large
pressure gradients that whip up high winds. The warmer the water, the greater
the likelihood that a storm will intensify to hurricane strength. And if the
greenhouse effect bakes the planet, the band of hot water between the Tropic of
Cancer and the Tropic of Capricorn will heat up further, turning more storms
into more hurricanes of more violent strength.

The characteristic path of hurricanes may change as well. In the north Atlantic,
hurricanes typically hit the West Indies or Florida and then veer north to wreak
havoc along the Carolina coasts. But as the pools of hot water widen
latitudinally due to ocean warming, hurricanes may track further north more
frequently, threatening cities like New York and Washington, DC, which seldom
see the powerful storms.

An increase in hurricanes certainly won't be the only result of global warming.
The phenomenon may melt the polar ice caps as predicted. raising the sea level
at coastal areas, but the change will occur slowly, giving urban planners time
to construct dikes and other structures. "In the short term, there is a much
greater potential for damage from an increasing incidence of hurricanes," says
Woods Hole senior scientist David Aubrey. "They're just hard to defend
against."