Facebook | Steven Mnuchin

US Treasury Sec. Mnuchin Calls Greta Thunberg's Climate Advice 'A Joke'

At the World Economic Forum in Davos, Switzerland, a war of words has erupted between 17-year-old Swedish climate activist Greta Thunberg and the Trump administration.

The latest to take a swipe at Thunberg was U.S. Treasury Secretary Steven Mnuchin during a press briefing.

Earlier in the week, Trump delivered a speech in which he both pledged to take part in an initiative to plant one trillion trees, and dismissed the worries of climate activists.

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As reported by Reuters, he specifically called out the "perennial prophets of doom," and referred to climate change activists as "heirs of yesterday's foolish fortune tellers."

In her address, Thunberg said that planting trees would not be enough and responded to Trump with a rebuke for inaction on climate change.

"Our house is still on fire," she said, referring to her remarks a year earlier in Davos. "Your inaction is fuelling the flames....Planting trees is good of course, but it is nowhere near enough of what is needed, and it cannot replace real mitigation and rewilding nature."

Thunberg has increasingly called for more aggressive action on climate change.

Instagram | @gretathunberg

She's been trying to get world leaders to read the 2018 Intergovernmental Panel on Climate Change report, listen to the science, and start making changes.

According to the report, the world must keep emissions of carbon dioxide below 420 gigtons for the best chance to keep global temperatures from rising by 1.5 degrees, an emissions mark the world is on pace to exceed by 2029.

Among her suggestions, one of Thunberg's more extreme measures caught the attention of Secretary Mnuchin: the complete divestment from fossil fuel investment immediately.

"Immediately end all fossil fuel subsidies and immediately and completely divest from fossil fuels," Thunberg urged in her speech. "We don't want these things done by 2050, or 2030 or even 2021 — we want this done now."

At a press briefing, Secretary Mnuchin took aim at Thunberg's speech, saying she was in no position to be giving economic advice.

Twitter | @stevenmnuchin1

"Is she the chief economist? Who is she? I'm confused," he said when asked how Thunberg's measures would affect the U.S. economy, before calling it "a joke."

"After she goes and studies economics in college, she can come back and explain that to us," Mnuchin added.

Online, many suggested that it was unlikely that a college degree would actually make a difference to Mnuchin.

"If you don't have an economics degree like Greta, they'll mock you for not having one. If you DO have one, as I do, they'll claim it's illegitimate," wrote Congresswoman Alexandria Ocasio-Cortez on Twitter. "Haters gonna hate & deniers will deny. They will deny logic, science, and environmental consensus in order to protect oligarchy."

Others added that what expertise Thunberg lacks in economics, Mnuchin lacks in climate science.

Instagram | @gretathunberg

"Mnuchin can tell us about climate change after he goes and studies climate science at college," wrote one person.

"Mnuchin can go to university and study climatology, and only then come back and lecture everyone on the climate," wrote another. "See how that sounds?"

It didn't take long for Thunberg to respond.

"My gap year ends in August, but it doesn't take a college degree in economics to realise that our remaining 1.5 degree carbon budget and ongoing fossil fuel subsidies and investments don't add up," she wrote on Twitter.

"So either you tell us how to achieve this mitigation or explain to future generations and those already affected by the climate emergency why we should abandon our climate commitments," she added.

For his part, Mnuchin has called the Trump administration's stance on climate change "misunderstood."

Facebook | Steven Mnuchin

There is a real misinterpretation of the U.S. policy," Mnuchin said, according to Reuters. "Let me be very clear: President Trump absolutely believes in clean air and clean water and having a clean environment."

However, the Trump administration has rolled back Obama-era environmental protections several times — most recently, the 2015 Waters of the United States rule, a move opposed by the EPA's Science Advisory Board.

h/t: Reuters, CNN, Associated Press