The 16-year-old Swedish climate activist Greta Thunberg has been named Time’s youngest “person of the year.”

The media franchise says on its website that Thunberg is being honored for work that transcends backgrounds and borders.

Thunberg was in Madrid on Wednesday to address negotiators at the U.N.'s COP25 climate talks.

Thunberg has become the face of the youth climate movement.

She has drawn large crowds with her appearances at protests and conferences over the past year and a half.

Some have welcomed her activism, including her speeches challenging world leaders to do more to stop global warming. But others have criticized her sometimes combative tone.

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