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"Speaking in the swing state of Iowa days before the presidential election, Hansen accused a senior administration official of trying to block him from discussing the dangerous effects of global warming. In the University of Iowa speech, Hansen recounted how NASA Administrator Sean O'Keefe told him in a 2003 meeting that he shouldn't talk "about dangerous anthropogenic interference" -- humans' influence on the atmosphere -- "because we do not know enough or have enough evidence for what would constitute dangerous anthropogenic interference."
But Hansen said that scientists know enough to conclude we have reached this danger point and that their efforts to get the word out are being blocked by the administration. "In my more than three decades in government, I have never seen anything approaching the degree to which information flow from scientists to the public has been screened and controlled as it has now," Hansen said. He added that although the administration wants to wait 10 years to evaluate climate change, "delay of another decade, I argue, is a colossal risk."
Senior administration officials deny Hansen's charges: O'Keefe spokesman Glenn Mahone said the administrator doesn't "recall ever having the conversation" on climate change that Hansen described, adding that O'Keefe "has encouraged open dialogue and open conversation about those issues."
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The ongoing sparring match between Hansen and his superiors underscores a broader tension between President Bush's top policy advisers and many senior U.S. scientists, who have loudly blasted the administration's approach to environmental questions in recent months. Nearly 50 Nobel laureates endorsed Sen. John F. Kerry (D-Mass.) for president; this year the Union of Concerned Scientists has collected more than 6,000 scientists' signatures on a letter questioning how the president applies research to policymaking. After the barrage of criticism, John H. Marburger III, Bush's top science adviser, told Science magazine that if the researchers continue their protests, they might alienate influential lawmakers who set federal science budgets."
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http://www.washingtonpost.com/wp-dyn/articles/A19162-2005Jan18.html