Study Says U.S. Winds Are Slowing

A new study holds potentially unwelcome news for wind power developers: wind speeds in the United States have dropped 15 to 30 percent over the course of about 30 years. And one possible cause, according to the authors, is climate change. The study, forthcoming in the Journal of Geophysical Research — Atmospheres, finds that “wind speeds generally across the country are declining, more so east of the Mississippi,” according to one of the authors, Eugene Takle, a professor of atmospheric science at Iowa State University. He said that in scattered pockets of the country, wind speeds have risen. The study used two data sets, one spanning the years 1973 to 2000 and the other from 1973 to 2005. The findings may not translate directly into trouble for the wind industry, Mr. Takle noted, since the measurements he used came from anemometer readings at airports — instruments that tend to be roughly 30 feet above the surface. By contrast, wind turbines are 250 to 400 feet tall – and the winds at that height might behave entirely differently, he said...NYTimes