Bill Nye Speaks Out on Climate Change in Shocking Rant: 'The Planet's on F---ing Fire'

America’s favorite scientist is bluntly warning fans about the seriousness of climate change.

Bill Nye, 63, made a cameo on Sunday’s episode of Last Week Tonight with John Oliver to explain the complexities of carbon pricing and the importance of Rep. Alexandria Ocasio-Cortez‘s Green New Deal.

In the satirical sketch, Nye, who hosted the PBS show Bill Nye the Science Guy for five years in the ’90s, ditches his trademark fun experiments, or what Oliver called “lighthearted demonstrations,” for an unfiltered approach to drive home the increasing risks of global warming.

“By the end of this century, if emissions keep rising, the average temperature on Earth could go up another four to eight degrees. What I’m saying is the planet’s on f—ing fire,” Nye said before engulfing a globe in flames.

“There are a lot of things we could do to put it out — are any of them free? No, of course not. Nothing’s free, you idiots,” he continued.

“Grow the f— up. You’re not children anymore. I didn’t mind explaining photosynthesis to you when you were 12. But you’re adults now, and this is an actual crisis, got it?” Nye concluded.

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Bill Nye | HBO
Bill Nye | HBO

The Green New Deal, which Ocasio-Cortez and Sen. Ed Markey introduced earlier this year, aims to achieve net-zero greenhouse gas emissions, create jobs and secure clean air and water for all.

During his appearance, Nye also tried his hand at explaining “carbon pricing” in laymen’s terms.

“When we release carbon, say, by burning coal or driving an SUV, all of us pay for that in the form of things like fires, floods and crop failures. Putting a fee on carbon creates incentives to emit less carbon, and, more importantly, it also incentivizes the development of low-carbon technology, which is huge, because that’s vital to reducing emissions globally,” he said.

Bill Nye
Bill Nye

“And because for some reason, John, you’re a 42-year-old man who needs his attention sustained by tricks, here’s some f—ing Mentos and a bottle of Diet Coke. Happy now?” Nye jokingly added, before demonstrating the reaction between the carbonated beverage and mints.

Nye previously called out climate change skeptics in season 1 of his Netflix series Bill Nye Saves the World with celebrity guests Karlie Kloss and Zach Braff.