Donald Trump's running mate is breaking with the Republican nominee's claim that climate change is not the result of human activity.
Vice presidential nominee Mike Pence said Tuesday "there's no question" that human activity affects both the climate and the environment.
At Monday's presidential debate, Democrat Hillary Clinton challenged Trump's views, saying: "Donald thinks that climate change is a hoax perpetrated by the Chinese. I think it's real." Trump interrupted with "I did not, I do not say that."
But in 2012, Trump tweeted that the "concept of global warming was created by and for the Chinese in order to make U.S. manufacturing non-competitive." He later claimed he was kidding, but he's also repeated the assertion that climate change is a hoax benefiting China. And in 2014, Trump tweeted: "Snowing in Texas and Louisiana, record setting freezing temperatures throughout the country and beyond. Global warming is an expensive hoax!"
Trump's campaign manager, Kellyanne Conway, tried to move discussion away from those comments Tuesday, saying on CNN that Trump believes "that climate change is naturally occurring" but the causes are not man-made.
The world's scientific organizations say the Earth's climate is changing because of the buildup of heat-trapping gases, especially carbon dioxide, from the burning of coal, oil and gas.
Pence, appearing separately on CNN, said, "let's follow the science," but he warned against rushing into environmental restrictions that drive jobs out of the country and put Americans out of work.
"What Donald Trump said was a hoax is that bureaucrats in Washington, D.C., can control the climate of the Earth," Pence said. "There's no question that the activities that take place in this country and in countries around the world have some impact on the environment and some impact on climate."
Conway dismissed Trump's previous tweets on climate change.
She questioned how "we're supposed to understand all of his policies" based on tweets or casual remarks he gave before entering politics – such as expressing support for the Iraq war on the Howard Stern show.
But she emphasized that Trump does not believe climate change is man-made.
"He believes climate change is naturally occurring. We don't know what Hillary Clinton believes because nobody ever asks her," Conway said. She derided Clinton's response in the debate, where she said that climate change is real, as "canned" and "scripted."
Clinton has proposed spending $60-billion to switch from dirty fossil fuels to cleaner energy. She promises to deliver on President Barack Obama's pledge that by 2025 the U.S. will be emitting 30 per cent less heat-trapping gases than in 2005.