Matthew Wielicki, a geochemist who frequently critiques climate science on social media, now leads the reconstituted U.S. Global Change Research Program—the federal office responsible for producing the congressionally mandated National Climate Assessment, a comprehensive report released every four years that shapes how Americans understand the risks climate change poses to infrastructure, lives, and the economy.
The Trump administration gutted the program last year, then brought it back under Wielicki's direction. He calls himself a "professor in exile" and has stated publicly that "a significant portion of the climate science literature is nothing more than stamp collecting." He's also suggested that climate scientists are faking data to make the world appear hotter. The White House declined to make him available for an interview but issued a statement claiming the program had "been used as a vehicle for political agendas instead of sound science."
The Mandate at Stake
The U.S. Global Change Research Program was created 36 years ago by a law signed under former President George H.W. Bush. It coordinates federal climate research across more than a dozen agencies and helps shape environmental rules, legislation, and infrastructure projects. The National Climate Assessment draws on hundreds of peer-reviewed studies to detail land productivity, flooding risks, water resources, fisheries, and ecosystems across the country.
Previous versions of the assessment have warned Americans about rising temperatures, increased flooding, and deadly wildfires. Shortly after the program was created, one of its early successes was revealing how a depleted ozone layer harmed Americans—a finding that led to regulations addressing the issue.
But the Trump administration's approach signals a sharp departure. White House Budget Director Russ Vought has long viewed the program as a source of "climate alarmism" that requires White House control, as he wrote in the Project 2025 conservative policy handbook organized by the Heritage Foundation. Wielicki said he'd like to speak about his work but only if the White House allows.
A Preview of What's Coming
The administration has already published one climate report, organized by Energy Secretary Chris Wright last year, that offers clues to the direction of the new assessment. That report was written by researchers who downplayed climate change effects and relied on work by scientists who other researchers criticized as misleading and riddled with errors. Those same scientists have been invited to participate in the National Climate Assessment process.
Wright's hand-picked researchers proposed a new National Climate Assessment that would emphasize the positive aspects of climate change, according to documents obtained by POLITICO from court filings in a lawsuit over the report. They cautioned that the most recent version "holds immense power" because it is "frequently cited in climate litigation" and used to justify regulations as well as lawsuits against fossil fuel companies.
Judith Curry, one of the scientists selected by Wright to author the DOE report, said the last version of the assessment "was all but useless" because it relied too heavily on extreme emissions scenarios. She said the forthcoming report would avoid that and expected it would expand on the DOE report's work. Curry said she would "provide high-level advice" to help craft the next version.
Wright told POLITICO in May that he expected to release a broader climate science product in the spring or winter. "We want to have public engagement, debates on this," he said. "Much more to come."
The Integrity Question
Michael Kuperberg, who served as executive director of the program during Trump's first term, expressed deep concern about the current direction. "It's not hard to find a small group of people who will give an inaccurate assessment of research," he said. The version the current Trump administration is assembling won't represent the larger field of science, but will degrade public trust in government research, he warned.
"The real risk here is the loss of integrity of the federal government," Kuperberg said. "If you cherry-pick a group of people that will say the sun's not going to rise tomorrow, how do you believe the next group of people?"
Wielicki's appointment and the administration's stated intentions raise questions about whether the National Climate Assessment will continue to serve as a credible, science-based policy tool or become something narrower—a document shaped by ideological preferences rather than the peer-reviewed research that has long defined the program's work.
Recent deadly heat waves in Europe killed more than 2,000 people. Climate data shows that Europe is the fastest-warming continent. Wielicki recently questioned this reality on X, asking whether it was "odd" that the region with the highest concentration of climate activists and policies was also warming the fastest.
The National Climate Assessment released during Trump's first administration was later dismissed by the former president, who said he did not "believe" the report was accurate. That report, as well as all previous versions, were deleted after Trump's second term began.
Why This Matters:
The National Climate Assessment shapes how federal agencies, Congress, and courts understand climate risks—informing decisions about everything from infrastructure spending to environmental regulations to disaster preparedness. When a program designed to synthesize peer-reviewed science is instead led by someone who publicly dismisses climate research and works alongside scientists who've been criticized for misrepresenting data, the integrity of that guidance erodes. Communities relying on accurate climate projections to plan flood defenses, water systems, or emergency response lose access to credible federal analysis. The shift also signals that scientific findings inconvenient to fossil fuel interests may be filtered out of official government reports—a departure from the program's original mission and a potential blow to democratic decision-making based on shared facts.