Happer, who served as director of energy research at the Department of Energy in the early 1990s under President George H.W. Bush, has championed the notion that we humans should increase rather than curb carbon dioxide emissions.

As The Washington Post reported Friday, Happer testified before the Senate in 2015 that the “benefits that more CO2 brings from increased agricultural yields and modest warming far outweigh any harm.”

Happer has also argued that today’s warming “seems to be due mostly to natural causes, not to increasing levels of carbon dioxide,” that children are being “force-fed propaganda masquerading as science” and has compared the “demonization of carbon dioxide” to the suffering Jewish people endured during the Holocaust.

“Carbon dioxide is actually a benefit to the world, and so were the Jews,” he told Andrew Ross Sorkin on CNBC’s “Squawk Box” in 2014.

E&E News was among the first to report on Friday’s meeting at Trump Tower. Although it remains unclear whether Trump is considering Happer for an administration position, the climate skeptic would be a fitting pick given the Republican’s previous choices.

Trump himself has dismissed climate change as “bullshit” and a Chinese “hoax.” He has also promised to pull the U.S. out of last year’s historic Paris climate agreement, in which nearly 200 countries pledged to reduce carbon emissions in an effort to keep global temperatures from reaching 2 degrees Celsius above what they were in pre-industrial times.

Last week, Natural Resources Defense Council President Rhea Suh called on Americans to fight back against what she described as the Trump administration’s and the Republican Party’s “war” on health and the environment.

“Already we’ve seen a set of cabinet nominees dominated by fossil fuel advocates, billionaires and bankers; a president-elect who says ‘nobody really knows’ what’s happening to our climate; and a full-on witch hunt for the experts who know the truth,” she said in a statement. “This is not normal.”