WASHINGTON ― Rep. Lamar Smith (R-Texas), a prominent climate change denier who chairs the House Science Committee, announced on Thursday that he is retiring from the House after his term ends next year.

“At the end of this Congress, I will have completed my six-year term as chairman of the Science, Space and Technology Committee,” he wrote in an email to supporters on Thursday afternoon. “I have one new grandchild and a second arriving soon! And I hope to find other ways to stay involved in politics.”

“With over a year remaining in my term, there is still much to do,” he added. “There is legislation to enact, dozens of hearings to hold and hundreds of votes to cast.”

The news, first reported by the Texas Tribune, comes as several other Republican lawmakers have announced recently that they are stepping down, with some facing tough primary challenges in response to the anti-establishment direction being taken by the GOP since President Donald Trump’s election.

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Smith, who was first elected to the House in 1986, is now the 20th Republican in the House to either resign this year or announce that they will not seek re-election in 2018.

Earlier this week, fellow Republican Texas Rep. Jeb Hensarling, who chairs the House Financial Services Committee, also announced his retirement after eight terms in Congress.

Several of the retiring representatives are moderate Republicans in swing districts, potentially facing an uphill battle for re-election, such as Rep. Charlie Dent (R-Pa.), Dave Trott (R-Mich.) and Dave Reichert (R-Wash.)

Smith likely had a safer route to re-election, though according to election data from the Daily Kos, Trump won the predominantly GOP district by just 10 points in 2016, compared to 2012 GOP presidential nominee Mitt Romney’s nearly 22-point margin of victory.

Derrick Crowe, a climate activist turned Democratic challenger to Smith, said that the GOP congressman’s retirement was “great news for the climate.”

In the Senate, two prominent Republicans have also announced their retirements in recent weeks: Sens. Bob Corker (R-Tenn.) and Jeff Flake (R-Ariz.).

Chris D’Angelo contributed reporting.