evidence: The study, which looked at just the United States, said that the turbines would cause more warming in the short term this century than the carbon dioxide America spews into the atmosphere would. [...] Wind advocates emphasized that the Harvard study doesn’t show turbines causing global warming, just local heating. [...] "The climate effect of burning fossil fuels is cumulative," Caldeira said in an email. "The longer you run a coal plant, the worse the climate change gets. In contrast, the climate effect of wind turbines is what it is. You build the wind turbine. Climate is affected. But as long as you run the wind turbine, the climate change doesn’t get any worse. So in the long run, as far as the climate is concerned, wind turbines are obviously better than fossil fuels."