Washington (CNN) William Happer, a Princeton atomic physicist and prominent skeptic questioning whether humans are causing rapid climate change, is joining the National Security Council as senior director for emerging technologies, according to NSC officials.

Happer, 79, is an emeritus professor of physics at Princeton who served in the Department of Energy under President George H.W. Bush in the early 1990s. He did not respond to CNN's requests for comment.

His public stance on climate change is in opposition to near universally accepted science.

He told CNN in April 2017 that carbon dioxide is not the toxic "pollutant" it's made out to be and "the temperature is not rising nearly as fast as the alarmist computer models predicted." He compared the Paris climate agreement, signed in 2015 by the US under President Barack Obama and 194 nations, to British Prime Minister Neville Chamberlain's appeasement of Hitler in the 1930s and said it was "silly" and "should be canceled."

President Donald Trump announced in 2017 that the US was withdrawing from the agreement, which aims to address and attempt to mitigate the consequences of greenhouse-gas emissions.

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