Al Gore’s post-electoral career as an environmental Cassandra has made him the butt of jokes for years in right-wing circles. (Mary Altaffer/AP)

In an alternate universe, Al Gore might have won the 2000 presidential election and made the United States the face of global efforts to stop Earth from warming further.

In the universe we inhabit, Gore lost. He went on to make a career out of advocating for environmental changes as an influential but relatively powerless private citizen.

Eighteen years later, climate projections are as dire as they’ve ever been, and the 45th U.S. president is a man who thinks a particularly cold winter in a single country is evidence against decades of recorded global warming.

“We are treating the atmosphere as an open sewer,” Gore told Trevor Noah on “The Daily Show” on Wednesday night, as he promoted his latest documentary series on the planet’s looming catastrophes. “That’s why the temperatures are going up, the water cycle’s being disrupted, and the fires! Look at the fires in California.”

He meant the Camp Fire this month, which The Washington Post’s Cleve R. Wootson reported was the most destructive in California’s history, killing dozens of people and destroying thousands of homes.

Noah tried to cut the gloom with gallows humors.

He cited a contrary opinion from “a very famous scientist who lives in the White House,” reading verbatim from President Trump’s recent interview with The Post, in which the president said he disbelieved his own administration’s report predicting that climate change will have catastrophic economic costs.

“A lot of people like myself — we have very high levels of intelligence, but we’re not necessarily such believers,” Trump had said.

He also called the oceans “very small” and said the air and water quality in the United States are “at a record clean.”

The audience laughed as Noah repeated the lines.

So did Gore — for a second.

Then, he said: “It’s really significant, Trevor, that Donald Trump is now the face of climate denial."

Gore’s post-electoral career as an environmental Cassandra has made him the butt of jokes for years in right-wing circles, which very much included Trump.

“Where is Al Gore now!” Trump said, retweeting a WordPress blogger in 2014. “Coolest Summer On Record In The US.”

Despite the odd cool summer or bad winter here or there, much of the world is seeing unprecedented heat waves. Spiking temperatures have helped kill off more than half the world’s wildlife since the mid-20th century, Alex Horton wrote in The Post.

Polar bears could go extinct by the mid-21st century as the ice caps decay, according to The Post’s Eli Rosenberg — something Gore has been warning about for years.

When Trump took office, Gore still thought he could make the president a convert, despite his past dismissal of an overwhelming body of scientific evidence.

“He tried for months to persuade President Trump to take climate change seriously — and thought there was a possibility he could come around,” as Amy B Wang wrote.

Gore’s hopes collapsed last year, when Trump pulled the United States from a global environmental pact known as the Paris accord.

By the beginning of 2018, Lindsey Bever reported for The Post, Trump’s obvious hostility to the pleas of climate advocates prompted scientists to nudge the famous Doomsday Clock two minutes closer to apocalypse.

“He is the principal global face of climate denial,” Gore repeated on Noah’s show. “And there are those who are still giving him their loyalty and trust, and I get that, believe me. But the vast majority of Americans, not to mention all around the world, are really kind of — they’ve had it with the constant craziness.”

Ever on the optimistic side of Armageddon, Gore hoped that voters would act where Trump has not — that one day the U.S. president might be an environmental champion.

Or that, too, might happen only in an alternate reality. As Kristine Phillips wrote for The Post, some researchers in our universe fear it’s already too late to prevent the biggest mass extinction event in 66 million years.

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