Good article by Chris Mooney, who has written book apparent link between hurricane/tropical cyclone intensity and global warming. Uses current Hurricane Dean as starting point, and includes:
To be sure, there’s a counterargument here: Data wasn’t as good on hurricane intensity in previous eras as it is today, when our measuring equipment is better than ever. Stronger storms may well have existed in the past, but we were simply incapable of detecting their true strength.
This is a serious objection, although it’s hard to know precisely how serious. Nevertheless, the fact remains that if you look at the official records, Dean now fits in to a staggering hurricane decade. That’s highly suggestive, if not definitive. And this staggering decade has occurred in part because of anomalously warm ocean temperatures in the hurricane-prone regions. Many scientists question whether you can explain these warm anomalies without invoking global warming as at least part of the cause.
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according to my ongoing “Storm Pundit” count of mega-hurricanes, Dean is the 10th Category 4 or 5 tropical cyclone observed globally this year. [Mooney lists the storms]
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by my own count, there were 19 of these intense storms in 2006, 22 in 2005, and 23 in 2004. Hurricane specialist Jeff Masters says the long term average is 17 — in which case all of these years would be above it and we might indeed be looking at a trend.
Hurricane Dean: 1 Of 10 Most Intense Atlantic Hurricanes Ever Measured