The '''anthropogenic global warming theory''' is one of several explanations for the slight warming of the earth's [[atmosphere]] recorded since the middle of the 19th or 20th centuries.
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The theory enjoys broad based political support from Liberals, Greens and the US [[Democratic Party]], and theory supporters frequently assert the existence of a "[[scientific consensus]]" favoring their viewpoint (see [[Politics of global warming]]).
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It should also be noted that President Bush's primary science advisor, Dr. John H. Marburger, supports anthropogenic global warming.<ref>BBC: [http://news.bbc.co.uk/2/hi/science/nature/6994760.stm "Bush aide says warming man-made"]</ref> A number of key Republicans support global warming as well.