UNITED NATIONS -- The U.N. Climate Action Summit kicked off in New York on Monday, but young environmental activists are already looking beyond the official gathering, a recognition that it will take sustained pressure to spur governments, many of them allied with the fossil fuel industry, to take meaningful action.
As the summit got underway, 16-year-old Swedish activist Greta Thunberg delivered a blunt and emotional speech excoriating world leaders for their inaction.
"You all come to us young people for hope. How dare you," said Thunberg, the most prominent face of the youth climate movement since launching school strikes last year. "You have stolen my dreams and my childhood with your empty words."
She added: "If you choose to fail us, we will never forgive you. We will not let you get away with this."
Those admonitions from Thunberg and other youth activists opened the daylong United Nations summit, featuring leaders from more than 60 countries along with businesses and other organizations. Each will be allowed three minutes to reveal plans to step up emissions reductions.
Organizers hope it will help build momentum to pressure national leaders indifferent to climate change, including those from the United States, Brazil and Australia -- world powers that will be noticeably absent from the summit stage.
But the young activists who have held massive rallies worldwide, demanding action instead of words in the fight against global warming, will probably be disappointed by what comes from this summit. They are already planning more protests for this Friday, for a meeting they expect to fall far short of their demands.
Niklas Hoehne, a partner at the German think tank NewClimate Institute, expects some announcements that will grow the ranks of small and medium-sized countries committing to move to renewable energy and zero emissions.
"But I don't expect a major breakthrough," he said. "It's an important political moment, but it will not do the trick."
U.N. Secretary-General Antonio Guterres urged world leaders to come not with "fancy speeches," but with concrete plans to cut more planet-heating pollution than their countries agreed to in the landmark 2015 Paris agreement.