Lighter than normal hurricane season expected, scientists say

Researchers at Colorado State University’s hurricane forecast team say this year’s hurricane season should be less punishing than previously thought. Despite the recent appearance of tropical storms Arthur and Bertha in the Atlantic basin, atmospheric conditions since the start of the season, June 1, suggest a light storm season in 2002.”The fact that we have witnessed two weak early season high latitude named storms does not mean we will have an active hurricane season,” says team leader William Gray. “In fact, due to recent changes in climate signals, we now believe the 2002 Atlantic basic hurricane season will be considerably below the long term average and much below what has been experienced in six of the last seven years.”In late May, the team had predicted 11 named storms, six hurricanes and two major hurricanes for the season. Now, this has been downgraded to nine named storms, four hurricanes and only one major hurricane. The conditions leading up to this revised forecast are unusual, says Gray, coming on rapidly and simultaneously. “The inhibiting changes include a cooling of Atlantic basin sea surface temperatures, a large increase in Atlantic sea surface pressures, and a strengthening of tropical Atlantic easterly trade winds and upper level tropospheric westerly winds,” he explains. Another factor inhibiting Atlantic hurricane activity is a strengthening of “El Nino” in the equatorial Pacific. In 1997, strong El Nino conditions led to a light storm season in the U.S.Human-induced factors, such as global warming, are not factors, Gray adds.He does warn that even on major hurricane can cause massive destruction, however. “For example, 1992’s Hurricane Andrew was the only major storm in a very inactive year but came ashore in south Florida and Louisiana and caused extensive damage.” Hurricane Andrew remains the second-largest loss event for insurers, behind the September 11, 2001 terrorist attacks.