A top government climate scientist told Congress today that political appointees without scientific backgrounds are corrupting the scientific process and confusing the public by censoring scientists and improperly editing their research on global warming.

“I believe that the nature of these edits is a good part of the reason for why there is a substantial gap between the understanding of global warming by the relevant scientific community and the knowledge of the public and policymakers,” said James Hansen, director of NASA’s Goddard Institute for Space Studies. “There has been so much doubt cast on our understanding that they think it’s still completely up in the air.”

Also sitting at the witness table were two former Bush administration political appointees — Phillip Cooney and George Deutsch — who have found themselves at the center of separate recent climate science controversies.

In January 2006, Hansen complained that NASA officials, including Deutsch, were insisting that his lectures, media interviews and papers be approved in advance by public affairs staff at NASA headquarters. Deutsch, a former intern for George W. Bush’s re-election campaign, had no scientific training.

‘Forcing Scientists to Parrot Propaganda’

“Why are public affairs offices staffed by political appointees?” asked Hansen, who said he testified today as a private citizen. “Their job should be to help scientists present results in a language that the public can understand. They should not be forcing scientists to parrot propaganda.”

Deutsch testified that high-ranking NASA officials were unhappy with Hansen after seeing a report on ABC’s “Good Morning America” by correspondent Bill Blakemore in December 2005. Blakemore, citing information from Hansen, reported that 2005 was tied to become the hottest year on record.

“Senior NASA officials conveyed to me that they were unaware of the release of this information being coordinated with headquarters or peer review,” Deutsch said. “The same senior NASA officials were, to say the least, upset by this procedural breach.”

Following news reports in which Hansen claimed he was censored, Deutsch resigned from NASA and the agency issued a new communications policy that emphasized openness among scientists and the news media.

Republicans Say Message Still Getting Out

Rep. Darrell Issa, R-Calif., pointed out that Hansen — who is in Al Gore’s documentary “An Inconvenient Truth” — is one of the most frequently quoted scientists on the topic of global warming.

“You’re one of the most easily Google-able human beings on the face of the earth,” Issa said. “The message is getting out, wouldn’t you say?”

Hansen acknowledged the message is getting attention but insisted the public is still confused about the level of scientific understanding on global warming.

Cooney resigned from his post at the White House Council on Environmental Quality in 2005 after The New York Times revealed the former oil industry lobbyist had edited government climate reports to downplay links between human greenhouse gas emissions and global warming.

Cooney also has no scientific training but testified today that he relied on information from the National Academy of Sciences and other sources.

“The comments and recommendations that I offered in reviewing executive branch policy documents on climate change were consistent with the views and exploration of scientific knowledge that many others in all three branches of our government were undertaking,” he told the committee. “I offered my comments in good-faith reliance on what I understood to be authoritative and current use of the state of scientific knowledge, and for no other purpose.”

The hearing was the latest of several to explore government censorship of climate scientists at NASA and the National Oceanic and Atmospheric Administration, or NOAA. It’s an issue that has received more attention from Democrats in Congress who accuse the Bush administration of clouding the accepted scientific consensus regarding climate change. Today’s hearing was held by House Oversight and Government Reform Committee Chairman Henry Waxman, D-Calif.