After incorrectly identifying the destructive power of Hurricane Katrina as a direct result of global warming, what Al Gore really needed was some bang-up hurricane seasons to back his claims and whip up public frenzy. Unfortunately for Al, that hasn't happened. No hurricane-strength storm made landfall in the US in 2006 and it appears that storm activity is once again going to fall far short of predictions for 2007.
Hurricane season is officially over on November 30, a date which soon approaches. September 2007 had the lowest tropical storm activity since 1977 and both September 2006 and October 2006 brought the lowest storm activity in 30 years. During the past 30 years, only 1977, 1981, and 1983 have had less activity.
The forecast for both years was for a fairly active season and as nature refused to adhere to the forecast and failed to whip up storms that would fulfill the projections, there was lots of backtracking and excuses for the dull season. Everything from wind shear to El Nino and the lack of dust in the atmosphere was blamed for the relative quiet. Only Chris Landsea, in an article in National Geographic explained that hurricane seasons naturally fluctuate and that storms as intense as Katrina have happened many times over in history but we didn't have the technology to track or measure them as we do today.
In the commentary, he and colleagues write that firm conclusions on the link between global warming and hurricane intensity must wait until the historical hurricane record has been reanalyzed with modern methods.
But even then, Landsea said, he expects the increase in intensity to be small.
"Theoretical and numerical models do suggest [hurricanes] will become more intense due to global warming, but by a fairly tiny fraction, about 2 percent for every degree Fahrenheit [0.5 degree Celsius]."
Moreover, much of the reason for the vast destruction of Katrina was the demographics, so many people living in a coastal zone prone to hurricanes and the fact that New Orleans lies below sea level.
"Scores of scientists and engineers had warned of the threat to New Orleans long before climate change was seriously considered, and a Katrina-like storm or worse was (and is) inevitable even in a stable climate."
Anyway, the 2007 season is another bust for Al Gore. Of course, the season isn't quite over with yet, and maybe nature will deign to hand Al a storm whose tales of destruction he can feed to a warming-hungry media and public. But as of today, it seems unlikely.