Hurricane season officially began in the Atlantic region on Friday, June 1, and the hurricane experts at Colorado State University, led by professor William Gray, are once again forecasting an active season. As VOA's Greg Flakus reports from Fort Collins, Colorado, they also see more danger from hurricanes in the years to come.

William Gray

The hurricane research facility here near the front range of the Rocky Mountains is a long way from the coastal areas most likely to be affected by hurricanes, but it is here that William Gray and his associates do their analysis, using data from both the Atlantic and Pacific oceans. They predicted an active season last year, but it turned out to be an unusually quiet season, with no hurricanes landing on the US coastline.

But researcher Phil Klotzbach says the warming of Pacific waters, known as the el nino effect, undermined the forecast. This year, he says, that is not likely to happen.

Philip Klotzbach

"The el nino that we had last year, which likely caused the season to come to an early end and caused a pretty inactive season, is diminished," he said. "We basically, right now, have neutral conditions and they have actually turned towards la nina or cool water conditions in the tropical Pacific. That generally relates to less vertical wind shear in the tropical Atlantic."

The hurricane forecast team at Colorado State is predicting 17 named tropical storms in the Atlantic between now and the end of hurricane season, November 30. The researchers expect nine of these storms to become hurricanes, with five of those becoming intense hurricanes, with winds of 177 kilometers-per-hour or more.

The report states a 74 percent chance that at least one major hurricane will make landfall on the U.S. coastline. There is a 49 percent chance that a strong hurricane will hit the Gulf of Mexico coast and an above-average chance that a major hurricane will strike Caribbean islands.

Professor Gray says this increased activity is part of an overall increase in storms that began in 1995 after around two decades of relative quiet. He says the years ahead will likely be quite rough for people in the hurricane-prone areas.

"People ask how long this active period will last. Well, nobody knows for sure, but, if the future is like the past, this active period will probably keep going another ten,15, 20 years or so," he said.

Gray says his estimates are based on past storm activity and factors such as salinity of ocean waters that cause variations in temperature. He dismisses the notion that hurricanes will grow stronger as a result of global warming caused by human activity.

"I do not believe at all that the build up of human-induced greenhouse gases, like CO2 or methane, are causing storms to be more frequent or more intense," he said. "The evidence is just not there."

Other scientists disagree on that point, but Gray and his team say they will stick to their methods, based on reliable data and historic weather patterns. They will continue to monitor the oceans in the weeks ahead and release an updated report sometime in August.