Swedish teenage climate activist Greta Thunberg has been named Time magazine's Person of the Year for 2019.
Editor-in-chief Edward Felsenthal made the announcement Wednesday during an appearance on NBC's Today show.
"She became the biggest voice on the biggest issue facing the planet this year, coming from essentially nowhere to lead a worldwide movement," Felsenthal said.
Thunberg is the youngest person to win the award after quickly evolving into one of the world's most prominent climate change activists.
Her Friday protests alone outside the Swedish parliament during school hours at age 15 helped trigger a global movement to fight climate change.
The movement, which became known as "Fridays for Future," prompted millions of people in about 150 countries "to act on behalf of the planet," Felsenthal said.
Felsenthal noted that Thunberg, now 16, "represents a broader generational shift in culture," with more youth advocating for change worldwide, including during demonstrations in places such as Hong Kong, Chile, Sudan and Lebanon.
Thunberg's straightforward speaking style captured the attention of world leaders, resulting in invitations to speak at several high-profile events, including at the United Nations and before the United States Congress.
During her appearance before U.S. lawmakers, Thunberg, who has Asperger syndrome, refused to read prepared remarks. She, instead, submitted the U.N.'s 2018 global warming report to them and declared, "I don't want you to listen to me. I want you to listen to the scientists, and I want you to unite behind the science."
One of her most memorable moments came at the U.N. Climate Change Summit in September, when she berated U.N. Secretary-General Antonio Guterres and other world leaders, declaring they had stolen her "dreams of childhood" with their "empty words."
"We are in the beginning of a mass extinction," she said, "and all you can talk about is money and fairy tales of eternal economic growth. How dare you!"
Those words resonated worldwide, energizing climate change activists and sparking a series of prompting scornful reactions from others.
Thunberg's dedication to fighting climate change also earned her a nomination for the 2019 Nobel Peace Prize.