350.org co-founder Bill McKibben is calling out Canadian Prime Minister Justin Trudeau for cheerleading “one of the greatest climate disasters on the planet.” And he’s got math to back that up.

Trudeau, McKibben writes, “sure is cute, the planet’s only sovereign leader who appears to have recently quit a boy band. And he’s mastered beautifully the politics of inclusion: compassionate to immigrants, insistent on including women at every level of government. Give him great credit where it’s deserved: in lots of ways he’s the anti-Trump, and it’s no wonder Canadians swooned when he took over. But when it comes to the defining issue of our day, climate change, he’s a brother to the old orange guy in Washington.”

Writing in The Guardian, McKibben acknowledges that “Trudeau says all the right things, over and over. But those words are meaningless if you keep digging up more carbon and selling it to people to burn, and that’s exactly what Trudeau is doing.”

McKibben recalls Trudeau’s appearance before fossil executives in Houston earlier this year, earning “ a standing ovation for saying: ‘No country would find 173 billion barrels of oil in the ground and just leave them there.’” The number represents the estimated volume of oil that could be recovered from the Canadian tar sands/oil sands.

“So let’s do some math,” McKibben offers. “If Canada digs up that oil and sells it to people to burn, it will produce, according to the math whizzes at Oil Change International, 30% of the carbon necessary to take us past the 1.5ºC target that Canada helped set in Paris. That is to say, Canada, which represents one half of 1% of the planet’s population, is claiming the right to sell the oil that will use up a third of the earth’s remaining carbon budget.

“Trump is a creep and a danger and unpleasant to look at,” McKibben concludes. “But at least he’s not a stunning hypocrite.”