When the House Science Committee meets Wednesday for another hearing on climate science, members will be hearing from a familiar set of voices and—likely—a well-trod path of arguments.
The hearing is on “assumptions, policy implications, and the scientific method,” and chairman Lamar Smith said the goal was to weigh in on “the importance of scientists adhering to the scientific method when they promulgate their theories or make hypotheses on climate change.”
It’s a topic that Smith has raised repeatedly; he has used his committee post to question the scientific consensus on climate change and raise accusations that government scientists have manipulated data to back an environmental agenda. And Wednesday’s hearing will bring back a trio of scientists well-known for raising their climate doubt on the Hill.
John Christy, director of the Earth System Science Center of the University of Alabama in Huntsville, has testified as a majority witness three times since Republicans took control of the committee in 2011, according to a review of the committee’s past climate hearings. Christy testified last year that “demonstrably deficient model projections are being used to make policy,” presenting his own research that he said cast doubt on human-caused climate change.
Judith Curry, who resigned from the School of Earth and Atmospheric Sciences at the Georgia Institute of Technology in January, has appeared twice before Wednesday’s hearing. In her most recent appearance before the committee in 2015, Curry highlighted “growing evidence that climate models are running too ‘hot,’” and questioned the role of humans in climate change.
The third majority witness, University of Colorado professor Roger Pielke Jr., has also testified before the committee twice before, and was called twice as a minority witness when Democrats controlled the committee. Although Pielke has said that humans are contributing to climate change, he has said there’s little evidence that links extreme storms to climate change.
Not only have all three made repeat appearances before the Science Committee, they’ve all become frequent guests for Republicans looking to introduce debate about climate change in hearings. For example, a climate hearing led by Sen. Ted Cruz in the Senate Commerce Committee in 2015 featured Curry and Christy; Pielke has appeared multiple times before the Senate Environment and Public Works Committee. The three were also among a list of scientists probed by Democratic lawmakers in 2015 for their links to the fossil-fuel industry.
Democrats invited Michael Mann, the Pennsylvania State University climatologist famous for the “hockey-stick graph” showing rising global temperatures.
Critics say that by rotating through a roster of climate doubters, Republicans are trying to create a feedback loop that prevents any action on climate change. David Titley, a professor of practice in the department of meteorology at Penn State, wrote in The Washington Post that “the strategic effect of participating at these hearings has been to sustain the perception of false equivalence, a perception only exaggerated by the majority’s ability to select a grossly disproportionate number of witnesses far removed from mainstream science.”
A committee aide said, “We were looking for people who had written or spoken before about the intersection between science and how science was being done … and how that relates to policy.” Smith said in an interview that this was a new topic for the panel.
Pielke said in an interview that “if you’re an expert that Congress deems relevant to what they’re doing, you have an obligation to participate,” but added that he sometimes wasn’t sure why Republicans would call him. Pielke has written in support of the findings of the United Nations’ Intergovernmental Panel on Climate Change and has backed a carbon tax, and said his main concern is getting political concerns out of scientific discussions.
“A lot of the internal politics of climate change are people calling names,” said Pielke. “We should show some tolerance to diversity of views, to people like Curry or Christy whose views are legitimate, instead of excoriating them, which hopefully the hearing won’t turn into. If we recognize that they’re part of a community, we could get to the difficult questions we need to answer.”
In an email, Curry said she was returning to the committee to “get climate research back on track and out of the gutter of political sniping at your opponents.”
Political sniping, however, has become somewhat commonplace on what was once a relatively sleepy committee. Smith has moved several bills meant to bring more transparency to government science but that Democrats say would effectively halt scientific work (two such bills will see floor votes this week). Republicans have also used subpoena authority to go after state attorneys general and scientists from the Environmental Protection Agency, NASA, and the National Oceanic and Atmospheric Administration, leading to concerns from the Left that Republicans are trying to chill the scientific process.
Democratic Rep. Paul Tonko said that while the committee debates the backing of climate change, “my whole concern is that we don’t reject science, that we embrace it and build a better world.”
But GOP Rep. Dana Rohrabacher said that, even with some repeat witnesses, it was important to show “legitimate arguments on both sides of the issue of global warming.” In an interview, Rohrabacher said that the witnesses were “experts who keep up on the news” and could offer something new even if they have testified before.
“The public is now going to see and hear on C-SPAN and through reporting two sides on a very important issue,” he said. “Otherwise they only get one side, because out in the media world rarely will the scientists who think global warming is fraudulent ever get quoted.”