Fridays for Future founder Greta Thunberg spent her 80th consecutive week of striking for climate action leading tens of thousands of demonstrators in a march through Bristol, England and delivering a speech in which she called for continued protests to pressure people in power to ambitiously address the planetary emergency.

"There will be a time when we will look back and ask ourselves what we did right now. How do we want to be remembered?" the 17-year-old Swede asked the crowd. Police said about 20,000 people braved the rain to see Thunberg speak, but multiple British news outlets reported estimates from organizers that the figure was closer to 30,000.

"This is an emergency. People are already suffering and dying from the consequences of the climate and environmental emergency, but it will get worse," Thunberg said. "And still this emergency is being completely ignored by the politicians, the media, and those in power. Basically, nothing is being done to halt this crisis despite all the beautiful words and promises from our elected officials."

School strike week 80. At least 30’000 people in the pouring rain today in Bristol! #fridaysforfuture #schoolstrike4climate #climatestrike pic.twitter.com/Xga0AwpUw5 — Greta Thunberg (@GretaThunberg) February 28, 2020

"I will not stand aside and watch. I will not be silent while the world is on fire. Will you?" Thunberg continued, provoking a roar of cheers. "World leaders are behaving like children, so it falls on us to be the adults in the room."

After more cheers, she added: "It should not be this way. We should not be the ones who will have to lead on this and tell the uncomfortable truth. Once again, they sweep their mess under the rug for us young people—for their children—to clean up for them."

"But we must continue, and we have to be patient and remember that the changes required will not happen overnight, since the politics and solutions needed are still far from sight," said the two-time Nobel Peace Prize nominee. "But if enough people are pushing for change, then change will come—and we are those people, and every single person counts."

Thunberg pointed to protests that recently squashed a planned expansion of the Bristol airport. That success shows that "activism works," she said. "So I'm telling you to act. If you look throughout history, all the great changes have come from the people. And we are being betrayed by those in power. And they are failing us, but we will not back down."

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Demonstrators marched through Bristol's streets following Thunberg's speech. On Thursday, youth organizers in Bristol said that they had "no time for being patronized" in response to local police warning parents about inadequate safety measures at the demonstration due to its expected size. As Common Dreams reported, Bristol Youth Strike 4 Climate tweeted a list of ways they planned to keep attendees safe.

The Guardian reported that 11-year-old Isaac and 15-year-old Maya Swann convinced their mother, Karen Davies, to bring them to the event in Bristol on Friday. Isaac said, "We wanted to see Greta and to join the march." Maya said: "We want to help make a change. She's really brave and inspirational, giving up part of her childhood to spread this message.”

Davies told the newspaper: "I was against them taking time off but last night they came to me and said they felt if I was their age I would be there. They were right. I'd be in the thick of it. I sent an email to the school and they were supportive. I think many schools see it as educational."

Amazing scenes from the #SchoolStrike in Bristol today The new generations coming together to speak truth to power after decades of government and corporate inaction. Photo credits: Mark Tyler #TellTheTruth #FridaysForFuture #ActNow #ClimateChange #EnvironmentalJustice pic.twitter.com/5zMdydnYUr — Extinction Rebellion UK (@XRebellionUK) February 28, 2020

Meanwhile, regional Fridays for Future groups and individual school climate strikers shared updates from protests across the globe on social media:

Climate strikers in Sydney, Australia—who are in their 25th week of protests—noted that earlier this week, oil giant Equinor backed out of controversial plans to drill in the Great Australian Bight. Fridays for Future Sydney tweeted: "This is just one step of many towards true climate justice. We aren't going anywhere."