LISBON: Climate activist Greta Thunberg arrived Tuesday by catamaran in the port of Lisbon after a three-week voyage across the Atlantic Ocean from the United States.

The Swedish teen sailed to the Portuguese capital before heading to neighboring Spain to attend the U.N. Climate Change Conference taking place in Madrid.

Her arrival coincided with a new scientific report saying there is mounting evidence that the world is getting ever hotter.

Thunberg hitched a renewable-energy ride from the United States, joining an Australian family on their 48-foot (15-meter) yacht.

The white catamaran carrying Thunberg sailed slowly up the River Tagus under blue skies and a stiff breeze. Thunberg's father, Svante, was also on the boat as it approached the Lisbon quayside.

Chile’s Environment Minister Carolina Schmidt, saluted Thunberg's role speaking out about the threat of climate change.

"She has been a leader that has been able to move and open hearts for many young people and many people all over the world," Schmidt said at the summit in Madrid.

"We need that tremendous force in order to increase climate action," she said.

Thunberg was due to be met in Lisbon by local dignitaries and other activists. Her representatives said they could not confirm when she would travel onward to the Spanish capital, 600 kilometers (370 miles) to the east.

She wanted a low-carbon form of transport to get to the climate meeting, which was switched at short notice to Spain from Chile due to unrest there.

The yacht, named La Vagabonde, leaves little or no carbon footprint when its sails are up, using solar panels and hydro-generators for electricity.

Meanwhile, a report by the U.N. weather agency released on the sidelines of the climate talks found that the current decade is likely to set a new 10-year temperature record.

Preliminary temperature measurements show the years from 2015 to 2019 and from 2010 to 2019 “are, respectively, almost certain to be the warmest five-year period and decade on record,” the World Meteorological Organization said.

“Since the 1980s, each successive decade has been warmer than the last,” the agency said.

While full-year figures aren’t released until next March, 2019 is also expected to be the second or third warmest year since measurements began, with 2016 still holding the all-time temperature record, it said.

This year was hotter than average in most parts of the world, including the Arctic. “In contrast a large area of North America has been colder than the recent average,” the U.N. said.

The World Meteorological Organization’s annual report, which brings together data from numerous national weather agencies and research organizations, also highlighted the impacts of climate change including declining sea ice and rising sea levels, which reached their highest level this year since high-precision measurements began in 1993.