As Hurricane Ivan and its powerful winds churned through the Gulf of Mexico, scientists told Congress today that global warming could produce stronger and more destructive hurricanes in the future.
Global warming will increase the temperature of ocean water that fuels hurricanes, leading to stronger winds, heavier rains and larger storm surges, the researchers told the Senate Commerce Committee.
However, the increase in ocean temperatures is unlikely to boost the average number of Atlantic hurricanes that form each year, they said.
Hurricane Ivan forced millions of people to evacuate a 400-mile (645 km) stretch of the US Gulf Coast.
The storm is classified as a Category 4 hurricane with maximum sustained winds of 135 mph (215 km/h) and has been blamed for 68 deaths and extensive damage in the Caribbean.
Ivan will be the third major storm to batter the US Gulf region during the past month. It is expected to make landfall early tomorrow morning.
The Republican-led panel heard testimony from several scientists who said emissions known as greenhouse gases were gradually raising the earth's temperature and would contribute to more extreme weather including flooding, drought and changing storm patterns.
"Warmer water temperatures will promote more intense tropical storms, but not necessarily make the frequency of those storms greater," said Mr Dan Cayan, a research meteorologist at the University of California in San Diego.
"An increase of even a degree or so in the right environment would cause intensities to increase," he said.
Some members of Congress, scientists and environmental groups contend that global warming is upsetting environmental balances by altering fragile weather patterns in the world.