Yesterday, the US House of Representatives Committee on Oversight and Government Reform held a hearing on “Allegations of Political interference with the Work of Government Climate Change Scientists.” As committee chair Henry Waxman noted in his opening statement, the committee had been investigating this matter for several months, and had good reason to be concerned:

According to the documents we reviewed, Administration officials sought to edit an EPA report (1) to add “balance” by emphasizing the “beneficial effects” of climate change, (2) to delete a discussion of the human health and environmental effects of climate change, (3) to strike any discussion of atmospheric concentrations of carbon because carbon levels are not a “good indicator of climate change,” and (4) to remove the statement that “changes observed over the last several decades are likely mostly the result of human activities.” Some of the most questionable edits were urged by Phillip Cooney, the former oil industry lobbyist who was the chief of staff of the White House Council on Environmental Quality.

If you’ve been following the news coverage of the Bush administration’s thorny relationship with science, you’re probably already aware of those incidents, as well as the problems that scientists working for NASA and NOAA experienced when trying to speak with the public and the media about climate change science. One new piece of alarming evidence that just came out yesterday, though, was a report called Atmosphere of Pressure from the Union of Concerned Scientists and Government Accountability Project.

Dr. Francesca Grifo of UCS was one of the witnesses testifying at the hearing, and she described the report’s findings (PDF of written testimony here). UCS mailed surveys to more than 1,600 climate scientists at seven federal agencies and received 279 responses; analysis of those responses found that:

Nearly half of all respondents (46 percent of all respondents to the question) perceived or personally experienced pressure to eliminate the words “climate change,” “global warming,” or other similar terms from a variety of communications.

Two in five (43 percent) perceived or personally experienced changes or edits during review that changed the meaning of scientific findings.

More than one-third (37 percent) perceived or personally experienced statements by officials at their agencies that misrepresented scientists’ findings.

Nearly two in five (38 percent) perceived or personally experienced new or unusual administrative requirements that impair climate-related work.

Nearly half (46 percent) perceived or personally experienced new or unusual administrative requirements that impair climate-related work.

One-quarter (25 percent) perceived or personally experienced situations in which scientists have actively objected to, resigned from, or removed themselves from a project because of pressure to change scientific findings.

Asked to quantify the number of incidents of interference of all types, 150 scientists (58 percent) said they had personally experienced one or more such incidents within the past five years, for a total of at least 435 incidents of political interference.

Also, 67% of respondents said that today’s environment for federal government climate research is worse compared with five years ago, and 45% said that their job satisfaction has decreased over the past few years. Both of these numbers were higher among NASA scientists – 79% and 61%, respectively.

During the hearing, Representative Darrell Issa seemed to be trying to discredit the UCS report, suggesting that UCS had cherry-picked those who’d be surveyed and had failed to subject its work to peer review. Grifo responded that they had used several sources to compile as comprehensive a list of scientists and had asked several scientific peers for feedback – and then Issa cut her off before she could finish responding to his attacks on their methodology.

Grifo emphasized that the important thing wasn’t whether the sample of respondents was representative, but the fact that there were at least 435 incidents of political interference with federal climate scientists.

Perhaps the most quotable line of the hearing came from Rick Piltz, who spent 10 years working for the government agency program office dealing with climate science and resigned in protest after he concluded that the politicization of climate science communication by the Bush administration was undermining the credibility and integrity of his program. (PDF of his testimony here.) In response to a question by Representative Sarbanes, Piltz noted that those seeking to discredit or downplay the widely accepted climate science have “a predatory relationship to the uncertainty language” that is an accepted part of science.