AS THE season for hurricanes cranks up, so do the arguments about what is causing them. Now a meteorologist claims that the apparent increase in recent years - blamed on global warming - is an illusion.

The supposed rise in hurricane frequency can be explained by better measurement techniques, says Philip Klotzbach of Colorado State University in Fort Collins. Klotzbach analysed the frequency and intensity of hurricanes over the past 20 years. The study that linked hurricanes to global warming used data going back over 35 years, but he argues that satellite records prior to 1984 are unreliable (Geophysical Research Letters, DOI: 10.1029/ 2006GL025881). "Most of this increase is likely due to improved observational technology," he says.

Judith Curry at Georgia Institute of Technology in Atlanta contests this, claiming that Klotzbach has "cherry-picked" his data. "It is completely incorrect to say that the data quality has been better in the last 20 years. In some cases it has degraded," she says. "Due to decadal cycles in the oceans, 20 years is way too short a time period to observe trends."
From issue 2554 of New Scientist magazine, 06 June 2006, page 19
(NewScientist, 06/06/2006)
http://www.newscientist.com/article/mg19025545.700-are-there-really-more-hurricanes.html