In a dramatic reversal of its previous position, the White House this week conceded that emissions of carbon dioxide and other heat-trapping gases were the only likely explanation for global warming. Citing the "best possible scientific information," an administration official, James Mahoney, delivered a report to Congress that essentially reversed the previous White House position set out by George Bush, who had refused to link carbon dioxide emissions to climate change.
Two years ago, when his administration last published a document claiming that global warming over the last few decades had been prompted by human behaviour, Mr Bush dismissed it as something "put out by the bureaucracy".
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Coming just days before the Republican convention opens in New York, it is thought to be another attempt by the administration to show moderate leanings. The report, which also quotes studies that indicate that carbon dioxide stimulates the growth of invasive weeds more than it does crops, is part of a regular series submitted to Congress to monitor global trends.
Mr Bush's former allies in the energy industry criticised the findings. Myron Ebell, of the Competitive Enterprise Institute, told the New York Times it was "another indication that the administration continues to be incoherent in its global warming policies". Environmentalists say the report's conclusions simply highlight the distance between what the Bush administration has done and what good science suggests should be done."
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http://www.guardian.co.uk/international/story/0,3604,1291813,00.html