On Tuesday, hundreds of top US scientists published an open letter calling on Donald Trump and the rest of the Republican Party to stay in the hard-won global climate change agreement ratified by the US this month.
Emphasizing the scientific consensus behind man-made climate change and the worry that the Earth is approaching “tipping points” after which ocean currents will change and ice sheets will disappear, 375 members of the US National Academy of Sciences called for US politicians — and in particular, the next president — to remain part of the climate pact.
“The political system also has tipping points,” the scientists wrote. “Thus it is of great concern that the Republican nominee for President has advocated US withdrawal from the Paris Accord.”
Trump has repeatedly voiced doubts about climate change. He told the Washington Post that "there’s a change in weather," but also that he is "not a great believer in man-made climate change." Perhaps most famously, he has said that the Chinese invented global warming.
He has also made clear as a presidential candidate that he intends to "cancel" the global accord signed in Paris last December, which President Obama and Hillary Clinton both tout as among their most significant foreign policy achievements.
“This agreement gives foreign bureaucrats control over how much energy we use on our land, in our country. No way,” Trump said in an energy policy speech in North Dakota in May. By July, the Republicans codified the rejection of the Paris agreement in their official party platform.
That's when Ray Weymann, a retired astronomer associated with the Carnegie Institution for Science, began talking with his colleagues in the National Academy of Sciences about penning a letter to denounce the GOP platform.
Weymann recruited Kerry Emanuel, climate scientist at the Massachusetts Institute of Technology; Benjamin Santer, a climate scientist at Lawrence Livermore National Laboratory; and George Field, an astrophysicist at Harvard, to put together the letter, and it soon accumulated hundreds of signatures.
The Trump campaign did not immediately respond to a request for comment on the letter.
The scientists hope that their letter will spur public discussion, and that these issues will get airtime at the first presidential debate next Monday.
"This is an issue that will define us," Santer said at Tuesday's press conference. "It would be paradoxical if the issue was not discussed by the candidates."
Emanuel told BuzzFeed News that if he were to talk to Trump in person, he would try to appeal to his sense of competition with China. "Where there is risk, there is opportunity,” he said. “We should be selling clean energy to China 20 years from now, and not buying from them."