From You Do Need a Weatherman:
In 2004, Florida was pounded with a record four hurricanes in a single season, a disaster that cost 117 lives and destroyed 25,000 homes. In early January, five days of torrential rains in California triggered mudslides that killed at least 10 people. The same storm brought blizzard conditions to North Dakota, where the wind chill dropped to 50 below. And while it was more a geological event than a climatological one, a magnitude-9 earthquake off the north coast of Sumatra generated a tsunami that has, to date, killed some 150,000 people.Christopher C. Burt, the author of the excellent and addictive ”Extreme Weather: A Guide & Record Book,” strives to put all this in context. He reminds us that, eons ago, the earth experienced some mind-boggling temperatures: there were glaciers in Wisconsin, and palm trees littered northern Canada. That’s climate, of course, not weather. Weather happens in the short term, and we humans haven’t been keeping reliable records all that long. ”In the United States,” Burt writes, ”weather records have been maintained by the official weather services since about 1870. In the 50 preceding years, records were kept intermittently by individuals and by some institutions, including the Smithsonian Institution.” The figures we have ”represent only a fraction of human experience with weather,” but may be used as a ”yardstick” to determine climatic trends. By this yardstick, the weather is not becoming more extreme.
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Burt spends but a single page on global warming. ”There is little debate over the fact that over the past 25 years or so global temperatures have risen significantly, and the trend has escalated since 1990.” Why? Well, he points out that many weather stations have been moved from cities to nearby airports, where acres of asphalt radiate more heat. Some weather stations, previously in the countryside, have been absorbed into urban areas, which are warmer in the winter.