Teenage climate activist Greta Thunberg has sailed into New York Harbour in a zero-carbon emissions vessel, completing her nearly 14-day journey from England to take part in a United Nations climate summit.

The 16-year-old Swedish schoolgirl, who set sail from Plymouth, England, on August 14, was greeted by cheers, chants and singing as her silver sailboat, the Malitzia II, cruised past the Statue of Liberty through choppy waves and rain to drop anchor in Manhattan’s yacht harbour.

“All of this is very overwhelming and the ground is still shaking for me,” a seemingly bashful Thunberg, clad in a dark blue jumpsuit, told a gathering of reporters and activists who greeted her and the crew of the Malitzia II on land.

“It’s insane that a 16-year-old had to cross the Atlantic Ocean to make a stand on the climate crisis. This of course is not something I want everyone to do,” she said.

Thunberg made her trans-Atlantic journey carbon emission-free by travelling on 18.3-metre yacht, which is equipped with solar panels and underwater turbines that produce electricity onboard, along with a large black sail carrying the message: “Unite behind the science.”

The boat has no shower or toilets, and those aboard including Thunberg’s father and crew members ate cold canned food throughout the trip.

Thunberg, who first drew international attention last year when she started missing school on Fridays to protest against political inaction on climate change, said she planned to take part in a demonstration outside the United Nations in New York on Friday.

Manhattan! pic.twitter.com/8SxPYk2WRk

— Greta Thunberg (@GretaThunberg) August 28, 2019

But first, she said, she planned to: “Eat fresh food, not freeze dried, not be wet and to clean myself.” Peppered with questions from reporters about her message for US President Donald Trump, a climate change sceptic, Thunberg suggested she was not interested in butting heads with the Republican.

“My message for him is just listen to the science, but he obviously doesn’t do that. No one has been able to convince him of climate change, the urgency, why should I be able to do that?” she said.

“So I’m just going to focus on spreading awareness.”

In addition to the UN Climate Action Summit in New York, Thunberg intends to attend the COP 25 climate change conference in Santiago, Chile, in December, planning to make her way there without using air travel.

-AAP