President Trump announced his decision to withdraw from the Paris climate agreement on June 1, after saying he would "cancel" the deal while on the campaign trail. (Reuters)

Former vice president Al Gore said he tried for months to persuade President Trump to take climate change seriously — and thought there was a possibility he could come around, until Trump announced he would pull the United States out of the Paris agreement in June.

“I thought, actually, there was a chance he might come to his senses,” Gore told late-night television host and comedian Bill Maher. “But I was wrong.”

Gore made an appearance Friday on HBO’s “Real Time with Bill Maher” to promote his second documentary about the threat of climate change, “An Inconvenient Sequel: Truth to Power.” His PowerPoint-heavy first film, “An Inconvenient Truth,” became a surprise hit when it came out in 2006 and is one of the highest-grossing documentaries in history.

The movies have bookended Gore’s efforts over the past decade to educate the public about climate change, an endeavor that has taken on heightened urgency in the Trump era, as the new administration seems bent on fighting a slew of environmental regulations.

Gore told Maher that, yes, he had visited Trump Tower in December at the invitation of Ivanka Trump to talk to Trump, then president-elect, about climate change — and that the “conversation continued after he went into the White House.” Though his efforts would prove to be fruitless, Gore said he was heartened by at least one development that followed Trump withdrawing from the Paris agreement.

“When he made his speech pulling out of Paris, I really was concerned that some other countries might use that as an excuse to pull out themselves,” Gore told Maher. “But the very next day, the entire rest of the world redoubled their commitment to the Paris agreement, as if to say, ‘We’ll show you, Mr. Trump.’ ”

Gore also addressed the idea of “tipping points” that had been introduced in “An Inconvenient Truth,” primarily whether Earth’s population had crossed a point of no return when it came to being able to reverse rising sea levels and other effects of human-caused climate change.

“The scientists still tell us no, we have not gotten to that point,” Gore told Maher. “We can still avoid the most catastrophic consequences if we start acting boldly now. And we have begun to start. But some tipping points have, unfortunately, been passed.”

The recent breaking off of a massive iceberg from Antarctica’s Larsen C ice shelf was one such tipping point, Gore said, adding that he took the news hard.

“But we still have the ability to control that pace of disappearance and sea-level rise, and we still have the ability to stop other ice sheets behind it from crossing. Now there’s some other tipping points that are kind of uncertain. We’re taking huge, dangerous risks now that we should not be taking.”

It was here that Maher couldn’t help but slip in a joke at Gore’s expense.

“So when the sea levels rise, obviously we could lose, like, Venice. We could lose Florida,” Maher said. He paused, then delivered the zinger. “And who would know better about losing Florida?”

Gore gave him a mildly reproving look as the audience groaned. The former Democratic presidential candidate famously lost the 2000 election to Republican George W. Bush after a too-close-to-call race in Florida triggered a tense recount in the state.

“Actually, I think I carried Florida,” Gore said, with a shrug and just a hint of a smile. “But that’s another — … we won’t go there.”

Gore moved the conversation swiftly back to climate change and refuted popular talking points against climate-change action. He also told Maher that promises to bring back coal-mining jobs were a disservice to former coal workers, who instead should get priority for jobs in renewable energy industries.

“We have an obligation to those miners,” Gore said. “They and their predecessors did help to build this country. They ought to be getting the training they need and getting the opportunities that are opening up.”

As The Washington Post’s Michael O’Sullivan wrote in his review of “An Inconvenient Sequel,” Gore in his second film remains equally dogged about his climate-change platform but this time “with a tone that feels, at times, midway between a sense of resignation and despair. Those emotions might not be entirely foreign to Gore himself, who speaks, in the film, of his frustration and his struggle to remain hopeful in the face of political inertia (or outright backpedaling).”

He addressed those political factors again on Friday, acknowledging that the United States needed to fix its democracy first before it could fix climate change. Gore briefly told Maher that he felt it was time to move from an electoral college to a popular-vote system for president, and that “lobbyists and fat-cat contributors hacked our democracy before Putin hacked our democracy.”

Finally, Gore asserted that Mars could not be a “backup planet” for the human population.”

“I’m all for exploring Mars. That’s an exciting prospect,” Gore told Maher. “But like you I’m against the illusion that we’ve got a backup planet. We couldn’t even evacuate New Orleans when Hurricane Katrina hit.”

Al Gore's second film in series of climate change documentaries follows the former vice president across the world exploring the impact of a warming planet. (Paramount Pictures)

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