Updated September 17, 2023 at 3:35 PM ET
Helen Mancini remembers the last major climate march in New York City, when then-teenage activist Greta Thunberg spoke to a crowd of thousands, demanding world leaders take action on global warming.
Mancini was in middle school at the time. She remembers turning to her parents in frustration.
"And I just looked at them and I was like, How could you not dedicate your lives to stopping this?" she said.
But the wave of massive youth climate protests subsided, stymied in part by the pandemic.
Now, four years later, protesters are again gathered in the city, and this time Mancini, now 16, is helping organize it.
This time, protesters are marching with a specific message for President Biden: it's time for the U.S. to move away from oil and gas.
"[This] march is piercingly clear about what needs to be done to actually solve climate," said Jean Su, energy justice director with the Center for Biological Diversity and one of the march organizers. "It's actually seeking the end of fossil fuels."
Protesters are calling on Biden to stop federal approvals of new fossil fuel projects, phase out oil and gas drilling on public lands, and declare climate change a national emergency. They want the U.S. to halt oil and gas exports, and transition to a reliance on renewable energy.
Burning fossil fuels like coal, oil and natural gas remains the primary driver of global warming.
Setting the stage for "Climate Ambition Summit"
Organizers hoped Sunday's march would be the biggest climate protest in the U.S. since the 2019 strike, which brought tens of thousands of people into the streets in Manhattan while millions more marched worldwide.
The march comes after a summer marked by extreme weather events exacerbated by climate change, from historic heat waves in the U.S., Europe and Asia, to the deadly wildfire in Maui and catastrophic flooding from Brazil to China to Libya.
And it comes just days before a "Climate Ambition Summit" hosted by United Nations Secretary-General António Guterres, aimed at pressuring world leaders to commit to more rapid emissions cuts. Guterres has said only countries that present credible new plans – including the phase-out of fossil fuels – will be invited to participate. Biden does not plan to attend.
Scientists say the world needs to limit warming to 1.5 degrees Celsius (2.7 degrees Fahrenheit) above pre-industrial levels to avoid the most catastrophic impacts of climate change. To meet that goal, the U.N. says emissions must fall 43 percent by 2030, compared with 2019 levels, and eventually reach "net-zero" by 2050 – which means contributing no new greenhouse gasses to the atmosphere.
In a report this month, the U.N. found countries are falling far short of meeting their existing climate targets, and warned there is a "rapidly narrowing window" in which to act.
Activists hope the summit will shine a spotlight on the role of fossil fuels, Su said.
"This is a top down – from the U.N. – pressure point, and it's being met with grassroots pressure from the bottom up in the United States," she said.
Challenging Biden as 'climate president'
Organizers say they're especially disappointed Biden hasn't kept a campaign promise to halt new drilling on federal lands. The administration has allowed oil and gas projects to move forward, notably the Willow project, a major oil development in Alaska, and the Mountain Valley Pipeline, which will carry natural gas from West Virginia.
"I think the reality now is that Biden hasn't been the climate president that he had promised," said Alice Hu, senior climate campaigner at New York Communities for Change.
In a statement, the White House defended Biden's climate record, pointing to last year's Inflation Reduction Act, which directs hundreds of billions of dollars toward incentives for renewable energy and other low-carbon technologies.
"President Biden has treated climate change as an emergency – the existential threat of our time – since day one," a White House spokesperson said.
The administration has also designated millions of acres of public lands off-limits to oil and gas development, and recently canceled contentious oil and gas leases in the Arctic National Wildlife Refuge.
But Hu says the administration must do more. She points out the U.S. remains one of the world's largest oil and gas producers. And she argues Biden is at risk of alienating younger voters.
"Does he want to be a candidate that enjoys high youth turnout in key swing states, or does he want to be a candidate that is not enjoying that?" Hu said.
'It's about our future'
Mancini agrees. Now a junior in high school, she's been organizing school strikes with the youth climate group Fridays for Future NYC since her freshman year. But she says she never got as much interest in her work from other students as when news of the Willow project approval went viral on TikTok.
"The Willow Project is something that Biden approved, and a lot of people in my generation know Biden approved it," Mancini said.
"That betrayal was so stark in that moment," said Keanu Arpels-Josiah, 18, also of Fridays for Future NYC.
Arpels-Josiah said he volunteered for the 2020 Biden campaign while still in middle school, because he believed Biden would be a "climate president." Now, he's marching to pressure that president.
In the days before the march, Arpels-Josiah has been busy. He traveled to Washington, D.C., for a rally on the Capitol steps, and met with U.N. officials. Balancing his senior year of high school and climate organizing is a challenge. He's behind on homework and stressed about when it will all get done. But, he said, he doesn't feel like he has a choice.
"I have the ability to take action, and if you have the ability to take action, you have responsibility for everyone who doesn't have that ability to take action," Arpels-Josiah said.
"And also, it's personal," he said. "It's about our future."
NPR’s Michael Copley contributed to this report. contributed to this story
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