Hurricanes gather energy from warm water at the ocean surface, he says. Cooler water churned up in choppy seas takes the strength out. Even a 1C drop in water temperature can have a significant effect by decreasing the amount of evaporation into the eye of the storm. Previous, less reliable methods of forecasting hurricane strength did not take the ocean-atmosphere exchange into account, according to Dr Emanuel. Hurricane Opal provided a good example of the meteorologists' inability to predict the strength of a storm.
Hurricanes are tropical storms brought about by heavy evaporation of water from the ocean's surface.
In addition to violent winds, the impact of heavy rain, waves and storm tides make hurricanes among the most dangerous kind of natural disasters. The BBC is not responsible for the content of external internet sites.