Scott Pruitt, administrator of the Environmental Protection Agency. Credit:Bloomberg "What the American people deserve, I think, is a true, legitimate, peer-reviewed, objective, transparent discussion about CO₂," Pruitt said in an interview with Breitbart's Joel Pollack. But officials are discussing whether the initiative would stretch across numerous federal agencies that rely on such science, according to multiple Trump administration officials, all of whom spoke on condition of anonymity. Energy Secretary Rick Perry, who once described the science behind human-caused climate change as a "contrived phony mess", is also involved in the effort, two officials said. The idea, according to one senior administration official, is "to get other federal agencies involved in this exercise on the state of climate science" to examine "what we know, where there are holes, and what we actually don't know".

US President Donald Trump, centre, speaks during the Unleashing American Energy event at the Department of Energy, as he seeks to reorient the government away from fighting climate change and toward American "energy dominance". Credit:Bloomberg Other agencies could include the Commerce Department's National Oceanic and Atmospheric Administration, the White House's Office of Science and Technology Policy and NASA, according to the official, all of which conduct climate research in some capacity. EPA officials on Friday declined to comment, and Department of Energy could not immediately be reached for comment. One of April's global "March for Science" demonstrations in Berlin. Credit:Getty Images A plethora of scientific assessments over the years have concluded that human activity - such as the burning of fossil fuels - is driving climate change, and it poses grave risks both to the environment and to human health. In its most recent report, the Intergovernmental Panel on Climate Change concluded that it is "extremely likely" that, since the 1950s, humans and their greenhouse gas emissions have been the "dominant cause" of the planet's warming trend.

But that conclusion, shared by the vast majority of experts in the United States and around the world, has done little to stop Pruitt, Perry and other administration officials from raising doubts. Energy Secretary Rick Perry, centre left, accompanied by Budget Director Mick Mulvaney, centre, and Scott Pruitt, right, speaks during a cabinet meeting last month. Credit:AP The idea of a "red team-blue team" exercise stems in part from a Wall Street Journal commentary by New York University professor Steven Koonin. Kelly Levin, a senior associate with the World Resources Institute's major emerging economies objective, wrote in a blog post last month that the kind of adversarial process Pruitt is advocating is better suited for policy debates than for scientific findings. Shenhua told ASIC that its mine on the Liverpool Plains would begin production in 2019. Credit:AP

"Scientific understanding, unlike proposals for what to do about a given problem, is well established through the scientific method," wrote Levin, noting that 97 per cent of peer-reviewed papers on climate change support the idea that humans play a contributing factor. "If skeptics want their voices heard in scientific discourse, they should try to get their findings published in the peer-reviewed literature. They would then be assessed on their merits through peer review." Some members of EPA's scientific rank-and-file, who spoke on condition of anonymity for fear of reprisal, questioned Pruitt's plan. US President Donald Trump speaks at the Department of Energy event on Thursday. Credit:Kevin Dietsch "It's an obvious attempt to cast doubt on climate science under the guise of a common sense-sounding process," said one EPA employee who focuses on climate issues. "But of course, we already have a process for scrutiny of the science - the peer review process is a much more robust assessment of scientific integrity than a childish colour war." The employee called the effort "incredibly insulting".

The efforts to question the existing science on climate change have raised questions both within the government and among industry officials about whether Pruitt intends to try to roll back the EPA's 2009 "endangerment finding", which determined that greenhouse gases posed a risk to public health and created the basis for Obama-era regulations on emissions from power plants, automobiles and other sources. Two people with knowledge of the red team-blue team undertaking - one inside the Trump administration and one lobbyist - said its purpose was not explicitly to help target the agency's 2009 finding that emissions of greenhouse gases linked to climate change constitute pollutants under the Clean Air Act, though that idea is still under discussion among administration officials US President Donald Trump questioned the link between human activity multiple times during the 2016 campaign, though he has not addressed the issue directly since his inauguration. In his most recent remarks, in an interview with Fox News Sunday host Chris Wallace in December, Trump said that "nobody really knows" if climate change is real. After the President announced a month ago that the US would be withdrawing from the 2015 Paris climate agreement, multiple reporters have asked White House officials to clarify the President's views on climate science. But they have declined to do so. Loading

Pruitt's EPA also took down an agency website in late April that was focused on climate change, and highlighted the scientific consensus that it is caused by humans. Washington Post