SAN FRANCISCO (CBS SF) — Thousands of Bay Area students joined a global youth strike on Friday to demand leaders take action on climate change.

San Francisco’s Market Street was filled with hundreds of middle and high school students from around the region who were marching instead of attending classes.

The marchers stretched for more than a block and disrupted traffic on Market Street — a main downtown thoroughfare — under the watchful eye of the San Francisco police.

Marching behind a giant ‘Climate Strike’ banner and carrying signs bearing their schools names, the students began their march at the office of House Speaker Nancy Pelosi and ended at the offices of U.S. Senator Dianne Feinstein before rallying in San Francisco’s Union Square.

“We are in a climate crisis,” said Isha Clarke of Youth Vs Apocalypse, one of the student activist groups that organized the march, at a rally in San Francisco’s Union Square. “There is no room for denial or fear.”

The marchers attached post-it notes on the front of each office’s building with comments including, “Don’t ruin our planet!” and, “Our climate is changing, why aren’t you?”

Feinstein drew attention in a viral video last month where she was seen rejecting a group of youth activists who demanded support of the bill. Her office did not respond to a request for comment on the strike.

“We have 12 years to save this planet – the only planet that we have,” Clarke told the crowd, referring to an October report from the Intergovernmental Panel on Climate Change which said that “rapid and far-reaching transitions’ must be made by 2030 to avoid worst effects of global warming.

The strike is part of the global Youth Climate Strike calling for politicians to take immediate measures to stave off an impending climate disaster.

“When we were trying to organize people and we were telling people to come to the march, the most common thing we heard was, ‘Who is going to listen to us, we’re just students,'” said Olivia Brune, co-organizer of a climate strike march in Alameda’s Crab Cove. “I want to tell people you don’t have to feel powerless, you don’t have to feel like because you’re young you can’t make a difference. We have voice, our voice matters.”

In Berkeley’s MLK Park, the sign held by Andrea Ascher Webber summed up their frustration. “My sign is ‘If you won’t act like adults, we will,” she explained.

That theme, that adults have failed future generations in this cause, was a common one. “Exactly. I mean there are so many educated, brilliant people in the world,” said Alameda march co-organizer Emma Kohler. “They know about the crisis, they’ve largely discovered the science but we aren’t actually doing enough about it. We’re just kind of sitting here, waiting for someone else to solve the problem.”

This is the second time in a year students across the Bay Area and the nation have walked out of class in protest. Last March, it was a nationwide action against gun violence. Kohler sees a parallel in the two marches. “Well I think it’s important for students to feel like they’re being heard,” she said.

So today, those students demanded action on a crisis that may not afford the planet much time, and these students have no time for the status quo. “Act like it,” said Brune. “Act like this is an emergency. Act like this is a crisis, because it is.”

“Scientists have repeatedly told us we need to act on it,” said Hannah Estrada, a San Francisco high school student “No one seems to want to fight for my future. If no one wants to fight for me, I’m going to have to fight for myself.”

Hannah, 15, was one of several youths who gathered Sunday at Art Build in San Francisco to make posters and prepare for the strike.

Jazea Smith, an 11th-grade student at Ruth Asawa School for the Arts in San Francisco, was among the marchers.

“We need action before it’s too late, and it’s almost too late,” Smith said. “The politics and economics and everything else that’s going on right now – there’s no point if our Earth is warming at such accelerated rates that we’ve never seen before.”

Local high school and middle school students from Oakland, San Francisco, Marin County and the Peninsula took part in the protest. The students are calling on both Feinstein and Pelosi to back the Green New Deal, as introduced by U.S. Rep. Alexandria Ocasio Cortez, D-NY.

Youth Climate Strike organizers in the U.S. are calling for Congress to adopt the Green New Deal and declare a national emergency of climate change.

“We, the youth of America, are striking because decades of inaction has left us with just 11 years to change the trajectory of the worst effects of climate change, according to the October 2018 UN IPCC Report,” according to a statement on the group’s website.

“We are striking because our world leaders have yet to acknowledge, prioritize or properly address our climate crisis.”

The site also calls for a halt to fossil fuel infrastructure projects, preserving public lands and wildlife and keeping water supply systems clean.

The strikers are also calling for setting emission standards and benchmarks for reducing greenhouse gases.

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