The 2007 Atlantic Hurricane season ends on December 1st with slightly fewer major storms than originally predicted. However, weather forecasters say the number and intensity of the storms each hurricane season is higher than normal, and likely to remain so for years. More from VOA's Bill Rodgers.
Hurricane Dean slamming into Mexico. Dean was one of two Category Five hurricanes in the 2007 Atlantic hurricane season that is now at an end.
Category Five hurricanes are the strongest -- but even lower ranked hurricanes and tropical storms can cause heavy flooding and destruction.
In all, there were 14 named storms during the 2007 season -- five of which were hurricanes. At the beginning of the season in May, scientists had predicted up to 17 named storms -- including three to five major hurricanes.
Gerry Bell is the lead hurricane forecaster at the National Oceanic and Atmospheric Administration's Climate Prediction Center. He says hurricane predictions have been close. "The forecasted range was pretty close to what we observed. But what we're not happy with is that we expected a lot more hurricane intensity and duration of the hurricanes and we just didn't see that," he said.
Factors such as the way winds change as they circulate in the atmosphere, or wind shear, prevented more hurricanes from developing this season. Yet the Atlantic hurricane season remains unusually active.
Bell add, "Since 1995, eight out of the last 12 seasons have been above normal. And this is in complete contrast to what we saw during the previous, inactive hurricane era that lasted from 1971 to 1994. During that 24-year period we only saw three above normal seasons. Now, we've seen eight out of the last 12."
Some scientists blame global warming for this higher hurricane activity. They say warmer ocean temperatures cause more intense hurricanes -- such as the Category Five Katrina that devastated New Orleans and the U.S. Gulf coast in 2005.
But Bell is not so sure. He says, "We really don't know enough about the global warming, or global climate change, or these naturally occurring climate patterns to really quantify how much impact each is having in a given season."
For 2008, forecasters are predicting another active hurricane season because current climate patterns are likely to remain unchanged for perhaps another decade.