Swedish climate activist Greta Thunberg inveighed against the sowers of “climate chaos” Tuesday at the World Economic Forum in Davos, Switzerland, offering a view of the world that stood in stark contrast to President Trump’s.

In two speeches at the conference, the 17-year-old Thunberg renewed the call to “start listening to the science” on climate change. The world, she said, needs to “treat this crisis with the importance it deserves.”

Thunberg’s remarks echoed her warning in Davos last year, when she told world leaders: “I don’t want your hope. I don’t want you to be hopeful. I want you to panic. I want you to feel the fear I feel every day. And then I want you to act.”

The Swedish teenager’s activism helped inspire a global climate action movement, which earned her Time magazine’s Person of the Year title in December.

“Without treating [climate change] as a real crisis, we cannot solve it,” Thunberg said at the annual conference, which brings together political and economic leaders from around the world.

In a second speech Tuesday afternoon, Thunberg said: “Our house is still on fire. Your inaction is fueling the flames by the hour. And we are telling you to act as if you loved your children above all else."

President Trump made his second appearance at Davos this year. While Thunberg and Trump did not mention each other directly in their speeches, their remarks represented a head-on collision of worldviews.

Trump said he was a “big believer in the environment” but did not single out climate change and lashed out at “alarmists.” He said the United States will participate in a plan to add 1 trillion trees worldwide — a plan that climate activists argued would not even begin to scratch the surface of the problem.

During her afternoon panel, Thunberg said, “Planting trees is good, of course, but it’s nowhere near enough of what is needed."

Her words echoed a common sentiment among climate activists, whose anger at world leaders and big businesses has gained renewed momentum amid the devastating wildfires that have wreaked havoc in Australia in recent weeks.

Thunberg is helping drive that conversation. “Not even catastrophes like these seem to bring any political action. How is this possible?” she tweeted last month, drawing the enmity of Australian Prime Minister Scott Morrison, who has continued to back Australia’s influential coal industry, despite research connecting it to climate change. Scientists say rising temperatures have increased the ferocity of this year’s fire season.

With Morrison absent from the Davos conference, much of the ire among climate activists was centered on Trump.

Ishaan Tharoor, Anne Gearan and Toluse Olorunnipa in Davos contributed to this report.

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