Hundreds of scientists blast Trump's stance on climate

Nearly 400 global scientists have signed an open letter slamming Republican presidential candidate Donald Trump for vowing to withdraw from the Paris climate accord, warning of dire consequences for the environment if he is elected.

"A 'Parexit' would send a clear signal to the rest of the world: 'The United States does not care about the global problem of human-caused climate change,'" the letter read.

"The consequences of opting out of the global community would be severe and long-lasting -- for our planet's climate and for the international credibility of the United States."

Posted on responsiblescientists.org on Tuesday, the letter is signed by 375 scientists from around the world, including the world-renowned British physicist Stephen Hawking and Nobel laureate Steven Chu, a former US energy secretary under President Barack Obama.

Most of the signatories are from the United States, with many from leading universities such as Harvard, Cambridge and Columbia.

The 2015 talks in Paris were attended by leaders of some 190 countries who agreed climate change is a danger and must be solved.

The accord and its national commitments marked "a small but historic and vital first step towards more enlightened stewardship of Earth's climate system," the letter said.

"Thus it is of great concern that the Republican nominee for president has advocated US withdrawal from the Paris Accord."

"Such a decision would make it far more difficult to develop effective global strategies for mitigating and adapting to climate change," it added.

The United States "can and must be a major player in developing innovative solutions to the problem of reducing emissions of greenhouse gases," the scientists said.

"Walking away from Paris makes it less likely that the US will have a global leadership role, politically, economically, or morally. We cannot afford to cross that tipping point."

When the publisher of the US journal Science asked the presidential candidates about their views on climate change, Trump replied that "there is still much that needs to be investigated in the field of 'climate change.'"

He raised the possibility of funding clean water initiatives, food growth for all and eliminating diseases like malaria instead.

Democratic nominee Hillary Clinton disagreed. "The science is crystal clear," she said. "Climate change is an urgent threat and a defining challenge of our time and its impacts are already being felt at home and around the world."

She also proposed that the United States generate half its electricity from "clean sources" within the next decade, including from a massive boost of solar power.

She would also "reduce American oil consumption by a third through cleaner fuels and more efficient cars, boilers, ships, and trucks."

All four candidates' responses to 20 key science questions can be viewed at http://sciencedebate.org/20answers.