claim: A paper by Ross McKitrick, an economics professor at the  University of Guelph, and Patrick Michaels, an environmental studies  professor at the University of Virginia, concludes that half of the  global warming trend from 1980 to 2002 is caused by Urban Heat Island.
evidence: McIntyre agreed, and made contact with University of Guelph economics professor Ross McKitrick, a senior fellow of the Fraser Institute which opposed the Kyoto treaty, and co-author of Taken By Storm : The Troubled Science, Policy and Politics of Global Warming.