Time magazine on Wednesday announced that teen climate activist Greta Thunberg is its 2019 Person of the Year. Time said Thunberg won the award "for sounding the alarm about humanity's predatory relationship with the only home we have, for bringing to a fragmented world a voice that transcends backgrounds and borders, for showing us all what it might look like when a new generation leads."

The 16-year-old Thunberg first made headlines last year with her solitary strike against climate change outside Sweden's parliament. Since then, she's inspired millions of supporters to rally in more than 150 countries.

In September, she scolded world leaders at the United Nations for failing to address climate change.

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"We are in the beginning of a mass extinction, and all you can talk about is the money and fairy tales of eternal economic growth," she said, as she fought back tears. "How dare you! For more than 30 years the science has been crystal clear. How dare you continue to look away and come here saying that you're doing enough when the politics and solutions needed are still nowhere in sight."

Thunberg, who was attending U.N. climate talks in Madrid on Wednesday, reacted to the news on Twitter.

Wow, this is unbelievable! I share this great honour with everyone in the #FridaysForFuture movement and climate activists everywhere. #climatestrike https://t.co/2t2JyA6AnM pic.twitter.com/u4JUD4cgCz — Greta Thunberg (@GretaThunberg) December 11, 2019

When asked by "CBS This Morning" in September how she found the confidence to speak so clearly, Thunberg said that "I just know what is right and I want to do what is right. I want to make sure I have done anything, everything in my power to stop this crisis from happening, to prevent it."

"I have Asperger's, I'm on the autism spectrum, so I don't really care about social codes that way," she added.

Greta Thunberg scolds world leaders at U.N.

In some cases, she said, her neurodiversity gives her an advantage. It "makes you different and makes you think differently," she said. "Especially in a big crisis like this one, we need to think outside the box, we need to think outside our current system, we need people who think outside the box and who aren't like everyone else."

Climate change activist Greta Thunberg attends the High-Level event on Climate Emergency during the U.N. Climate Change Conference (COP25) in Madrid, Spain December 11, 2019. SUSANA VERA / Reuters

This year's Time Entertainer of the Year goes to Lizzo. The "Good as Hell" singer often incorporates themes of confidence and self-love into her music.

The U.S. women's national soccer team clinched Time's Sports Figure of the Year.

Time earlier released a list of Person of the Year finalists, which included Thunberg, President Donald Trump, House Speaker Nancy Pelosi, the anonymous whistleblower, Rudy Giuliani, soccer star Megan Rapinoe, New Zealand Prime Minister Jacinda Ardern, Facebook CEO Mark Zuckerberg the Hong Kong protesters.

Last year, slain Washington Post journalist Jamal Khashoggi and other journalists that Time magazine called "the guardians" were named Person of the Year.