Scientists Predict More Intense Storm Seasons

Mr. McCarthy, who spoke during a conference call organized by the Center for Health and the Global Environment at Harvard Medical School in Boston, said, "Warmer seas fuel the large storms forming over the Atlantic and Pacific, and greater evaporation generates heavy downpours."

Paul Epstein, associate director at Harvard Medical School's Center for Health and the Global Environment, said more powerful hurricanes?with stronger winds, higher storm surges and heavier downpours?would have an even greater potential for damage, including higher risks to human life and public health, more floods and mudslides, and increased coastal erosion and damage to coastal buildings and infrastructures.

"This is the pattern that we already may be seeing related to the overall increase in extremes," Mr. Epstein said.

Conference-call panelists observed that consequences of global warming appear to include rising sea surface temperatures and higher overall energy fluctuations at the tropical ocean surface.

The panelists said this increased ocean-surface disequilibrium may be creating more intense tropical storms. In the Pacific, they noted, a large ocean-water area two degrees warmer than average spawned 20 typhoons this season.

Among the typhoons, eight hit Japan, and meteorologists there have openly attributed that battering to global warming.

"Global warming is manifested in many ways, some unexpected. Sea level has risen 1.25 inches in the past 10 years as a result of warming of the oceans and glacier melting," added Kevin Trenberth, head of the Climate Analysis Section at National Center for Atmospheric Research in Boulder, Colo.

"The evidence," said Mr. Trenberth, "strongly suggests more intense storms and risk of greater flooding events, so that the North Atlantic hurricane season of 2004 may well be a harbinger of the future."

Matthias Weber, senior vice president and chief property underwriter of the U.S. Direct Americas division of Swiss Re, commented that the insurance industry has already been seeing the signals of changing weather patterns.

"Not since 1886 have four hurricanes hit one state in a single season," noted Mr. Weber.

This year, 22 percent of Floridians were affected and two million claims generated by hurricanes and tropical storms," he said. "In 2005, we expect the demand for catastrophe reinsurance to continue to rise. Over the last 10 years, demand has increased about 10 percent per year."