Urban Heat Island effect is possible cause of 50+% of all U.S. warming since 1940's. Land-use factors are a major 'forcing' in climate change that IPCC and U.S. politicians won't admit to. They should because their own parking lots, bureaucrat palaces and roads are causing the D.C. warming, not CO2. As can be seen, nearby states are cooling or have little warming over last 10 years versus large warming in D.C. metro area. Corrected image 8/22/09. Temperatures listed on image are degrees/decade trend. (click to enlarge image)
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