OSU climatologist takes stand on warming | The Columbus Dispatch

Many scientists are reluctant to speak out and fear accusations of bias, said Michael Nelson, an environmental philosopher at Michigan State University.

"They are really worried that their credibility is at stake," he said.
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Nelson weighed arguments in more than 50 papers published by other researchers, and he concluded that scientists should act as advocates.

"As citizens in a democracy, they have an obligation to do it," Nelson said.
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Not everyone believes that Thompson is presenting himself as an advocate. Raymond Bradley, director of the Climate System Research Center at the University of Massachusetts, Amherst, said he thinks that Thompson is merely outlining options.

Bradley also said that climate scientists can offer opinions because they know what they're talking about.

"It would be like going to see a doctor who deals with broken legs because you have a broken leg," Bradley said. "Would you take his advice, or the advice of some guy down the street?"