The White House has removed the scientist who oversees the National Climate Assessment, the federal government’s definitive report on climate change, The New York Times and The Washington Post reported Monday.

Michael Kuperberg, a climate scientist and executive director of the U.S. Global Change Research Program (USGCRP), was reportedly told Friday that he would no longer lead that organization.

Kuperberg, who has led USGCRP since July 2015, had been expected to stay on through the publication of the Fifth National Climate Assessment. The congressionally mandated, in-depth federal assessments are due every four years. The last report came out in 2018.

“Mike called me on Saturday and said he was just notified that he was let go, that his detail was over and that he should go back to the Department of Energy,” Donald Wuebbles, a climate scientist at the University of Illinois and co-author of the fourth climate assessment, told the Post.

Kuperberg was “shocked” by his ouster, Wuebbles told the Post.

“He was extremely dedicated,” Wuebbles said. “He did a very good job of figuring out how to walk that political line. He had no idea it was coming.”

The White House did not immediately respond to HuffPost’s request for comment.

David Legates, a deputy assistant secretary at the National Oceanic and Atmospheric Administration, is expected to replace Kuperberg, the Times and the Post reported.

Legates has falsely claimed, among other things, that increased levels of carbon dioxide in the atmosphere are good for the planet and dismissed his critics in the scientific community as “a bunch of thugs.” 

Kuperberg’s removal and the expected appointment of Legates appear to mark the latest efforts by the White House to kneecap U.S progress on climate science, which have included reversing Obama-era clean energy policies.

The Trump administration tried to bury the Fourth National Climate Assessment by releasing it the day after Thanksgiving in 2018.

That report concluded that global temperatures are “rising more rapidly than anything modern civilization has experienced” and that “this warming trend can only be explained by human activities, especially emissions of greenhouse gases into the atmosphere.”

But Trump and his allies dismissed the report’s findings.

“I don’t believe it,” Trump said at the time.

Last month, E&E News reported that the Trump administration was delaying work on the Fifth National Climate Assessment.

• This article originally appeared on HuffPost.