Reference
Khandekar, L. 2003. Comment on WMO statement on extreme weather events. EOS, Transactions, American Geophysical Union 84: 428.
What was done
The author briefly reviews what he learned about extreme weather events in Canada in the course of conducting a study of the subject for the government of Alberta; and he mentions the findings of several other recent studies of the subject.
What was learned
Khandekar says his research led him to conclude that "extreme weather events such as heat waves, rain storms, tornadoes, winter blizzards, etc., are not increasing anywhere in Canada at this time." He additionally notes that a recent special issue of Natural Hazards (Vol. 29, No. 2, June 2003) concludes much the same thing about other parts of the world. In this context, he cites a recent survey article by Robert Balling that concludes "there is no significant increase in overall severe storm activity (hurricanes, thunderstorms/tornadoes, winter blizzards) across the conterminous United States," as well as an article by Stanley Changnon, which concludes that "increasing economic loss due to weather extremes in the conterminous United States is a result of societal change and not global warming."
What it means
Contrary to the recent statement of the World Meteorological Organization on extreme weather events, which that organization suggests are increasing in association with global warming (and for which Khandekar chastises them for not knowing better), there are no significant increasing trends in these phenomena, as may readily be verified by perusing the Journal Reviews we have archived in our Subject Index under the many sub-sections of the general heading Weather Extremes.
Reviewed 26 November 2003