Hurricane Season – Are the Storms Getting Severe because of Global Warming?

May 10th, 2006

Hurricane

Hurricane season is just around the corner. There has been concern that global warming may be causing the increase and severity of the hurricane storms. One research project from the University of Virginia reported their view about hurricanes and global warming in the May 10th issue of the journal of Geophysical Research Letters.

The researchers studied the water temperatures as the hurricanes passed through to see if this was the cause of the increase in storms. They found that warmer water temperatures were found in only one half of the storms over the last 25 years. They believe that there are other factors contributing to the increased number of hurricanes.

"It is too simplistic to only implicate sea surface temperatures in the dramatic increase in the number of major hurricanes," said lead author Patrick Michaels, professor of environmental sciences and director of the Virginia Climatology Office at the University of Virginia.

Water temperature plays only part of the equation in a storm developing into a hurricane. The water temperature must cross a threshold of 89 degrees Fahrenheit. Other factors such as the atmosphere take over in creation a hurricane.

"At that point, other factors take over, such as the vertical wind profile, and atmospheric temperature and moisture gradients," Michaels said.

Michaels does not believe that global warming is to blame completely for the increase and severity of the hurricane season in the last few years. Other environmental changes can contribute the changes in the hurricane frequency which may be just a cycle of storms.

"The projected impacts of global warming on Atlantic hurricanes are minor compared with the major changes that we have observed over the past couple of years," Michaels said.

"Some aspects of the tropical environment have evolved much differently than they were expected to under the assumption that only increasing greenhouse gases were involved. This leads me to believe that natural oscillations have also been responsible for what we have seen," Michaels said.

Michaels does warn hurricanes could become more frequent with the effects of global warming.

"In the future we may expect to see more major hurricanes," Michaels said, "but we don't expect the ones that do form to be any stronger than the ones that we have seen in the past."