Youth climate activist Greta Thunberg, 16, criticized world leaders and “older generations” Tuesday for their inaction on climate change.

In a speech at the R20 Austrian World Summit in Vienna, Thunberg cited devastating findings from a report released last year by the United Nations Intergovernmental Panel on Climate Change. The report found that the world needs to decrease emissions by 45 percent by 2030, or the atmosphere will rise to 1.5 degrees of warming. This could cause multiple feet of sea level rise and endanger tropical coral reefs.

“It is we children and future generations that are going to suffer the most from these consequences if we fail. It should not be up to us to take responsibility, but since most world leaders are behaving like children, we have no other choice. The older generations have failed us. Our political leaders have failed us,” Thunberg said.

“Our political leaders can’t seem to think beyond the next election, and that must come to an end. This ongoing inaction of people in power and the companies responsible will, in the future, no doubt be remembered as a crime against humanity,” she added.

Thunberg called on the audience to take action and consider how they will be remembered by their grandchildren and future generations.

“If people really knew the full consequences of the climate crisis, they would join us on the streets, striking from their work, moving on from words to action,” Thunberg said. “Because the biosphere doesn’t care about empty words. The biosphere doesn’t care about what we say. It only cares about what we actually do.” Read more

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