Greta Thunberg, the 16-year-old Swede and face of the youth climate change movement, arrived in New York City on Wednesday after setting sail two weeks on a solar-powered racing yacht from England. A substantial crowd greeted her after she was escorted into New York harbor by 17 sailboats — one for each of the U.N.’s “sustainable development” goals.

“It is insane that a 16-year-old would have to cross the Atlantic Ocean to make a stand,” Thunberg said at a press conference after she arrived around 4:00 p.m. Eastern Time. “The climate and ecological crisis is a global crisis, the biggest crisis that humanity has ever faced, and if we don’t manage to work together and to cooperate and to work together despite our differences, then we will fail.”

She told reporters that fossil fuels should be kept in the ground and that the world needs to “stop its war on nature.”

Thunberg gained international attention just more than a year ago when she called on students around the world to take part in a school walkout to protest climate change, a movement she has dubbed #FridayforFuture.

She said at the press conference that the Guardian newspaper covered that she will join the ongoing school strike at the United Nations headquarters in New York City on Friday:

Thunberg’s team earlier announced that she is taking a “sabbatical” from her high school students to attend a September 21 youth summit at the U.S. and another U.N. climate summit on September 23:

She will then travel in the United States, Canada, and Mexico before attending another U.N. summit in Chile in December.

Thunberg also has said she is not sure how she will return to Sweden when her travels are complete.

Her idea for a carbon-free trans-Atlantic trip has generated controversy after news broke that the sailing team that brought her to the U.S. will be flying back, as will several others who are flying from Europe to take the boat back across the Atlantic.

Thunberg’s team has countered the criticism and has said the flights will be “offset.”

Left-wing media praised Thunberg in coverage of her arrival in New York City and dissed Trump with headlines like these: “Greta Thunberg, Climate Activist, Arrives in NY With a Message for Trump” (New York Times); “A Teen Activist Refused To Take a Gas-Guzzling Plane to U.N. Summit: She Just Arrived by Boat to Cheers” (Washington Post); and “Greta Thunberg tells Trump to ‘listen to the science’ as she arrives in New York (the Guardian).

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