After sailing on a catamaran for three weeks from New York City, teen climate activist Greta Thunberg arrived in Lisbon, Portugal, on Tuesday, AP reports.
Why it matters: Her trip comes as a new scientific report says there is more evidence than ever that the world is getting warmer, per AP. Thunberg opted to take an emission-free catamaran to travel back and forth between the U.S. and Europe ahead of significant climate summits.
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