Ten years after the Oscar-winning documentary "An Inconvenient Truth," Al Gore is concerned that a potential Donald Trump presidency could roll back progress in the fight against climate change.
"He has said some things on the climate crisis that I think should concern everyone,'' the former vice president told Anne Thompson in an exclusive interview on TODAY Monday.
"I'm not Pollyanna-ish, but I do think that there is still some basis for hope."
In "An Inconvenient Truth,'' Gore used charts and graphs to make the connection between increasing carbon emissions and the changing climate. To mark the 10th anniversary of the film's release on Tuesday, Paramount is offering free downloads of it on Amazon, XFINITY on demand, iTunes and other digital retailers.
RELATED: Al Gore takes on global change in ‘The Future’
Trump has called climate change a hoax created by China.
"President [Jimmy] Carter said that he hopes [Trump] will be malleable, so I don't know,'' Gore said before laughing.
Gore called the tone of the presidential campaign in which Trump is the presumptive Republican nominee "unusual."
"I'm one of the millions who sometimes just does a double take: 'Whoa, what was that?''' Gore said.
While numerous prominent Republicans have denied that climate change is real, Gore believes the fight against climate change cuts across party lines.
"I'm proud to have some Tea Party allies,'' he said. "What's being called the Green Tea Party."
RELATED: Al Gore to Melissa McCarthy: 'You make me laugh'
Gore, who won a Nobel Peace Prize in 2007, still gets attacked for predictions in the film.
"It's not unusual to see attacks on a messenger by people who don't like the message,'' Gore said. "I don't own a private plane. My house runs on 100 percent renewable energy. I do walk the talk."
While he has praised Democratic candidates Bernie Sanders and Hillary Clinton for addressing climate change, he has not specifically endorsed either one for the presidential nomination. He said he plans on backing whomever secures the Democratic nomination.
Follow TODAY.com writer Scott Stump on Twitter.