End of Hurricane Season

Oct 13, 2010

Q:   Nov. 30 is the end of hurricane season. Why are there so many hurricanes in some years, such as in 2005?

A:  That’s a question that a lot of people are asking, says John Nielsen-Gammon, professor of atmospheric sciences at Texas A&M University who also serves as State Climatologist.  “There were more hurricanes and tropical storms in 2005 than any year in at least 70 years,” he explains.

“A lot of fingers are being pointed at global warming for the rise in severe storms.  There are a lot of studies being done in this area, and global warming appears to be at least a strong contributing factor.  We know that some areas of the oceans are warmer than in years past, and this can contribute to more intense storms.

Q:  What specific areas of water are warmer?

A: The Atlantic Ocean, Nielsen-Gammon says, is scientifically proven to be warmer than normal.  “Large areas of the Atlantic are at least one degree warmer than in years past, and this goes back to 1995,” he points out.  “So we have had a decade of warmer water there, and that’s where hurricanes form.  The long-range outlook tells us that this warming trend could continue another 5 to 20 years.  Since warmer water means stronger storms and hurricanes, it could mean stronger storms in the future.  There were three hurricanes in 2005 that reached category 5 status –the strongest level – but it remains to be seen if that will happen in the years to come.

Weather Whys is a service of the Department of Atmospheric Sciences at Texas A&M University.