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FILE - In this April 15, 2012 file photo, a woman is framed in the doorway of a damaged home in Thurman, Iowa, after it was destroyed by a tornado the night before. In 2012 many of the warnings scientists have made about global warming went from dry studies in scientific journals to real-life video played before our eyes. (AP Photo/Nati Harnik, File)

Associated Press
FILE - In this April 15, 2012 file photo, a woman is framed in the doorway of a damaged home in Thurman, Iowa, after it was destroyed by a tornado the night before. In 2012 many of the warnings scientists have made about global warming went from dry studies in scientific journals to real-life video played before our eyes. (AP Photo/Nati Harnik, File)
FILE - In this April 15, 2012 file photo, a woman is framed in the doorway of a damaged home in Thurman, Iowa, after it was destroyed by a tornado the night before. In 2012 many of the warnings scientists have made about global warming went from dry studies in scientific journals to real-life video played before our eyes. (AP Photo/Nati Harnik, File)
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