As Sen. Bernie Sanders stood with activists striking for climate in Iowa on Friday morning, the act of solidarity was repaid in kind later in the day as key leaders of the youth-led movement in the U.S. officially endorsed the Vermont senator's 2020 presidential bid.

"Historically, movements have had young people at the forefront and the climate movement is no exception," Hirsi said. "Bernie has been there since day one fighting alongside all the young people across the country." —Isra Hirsi, US Youth Climate StrikeAs youth members of the Sunrise Movement targeted Democrats who have refused to endorse the Green New Deal with sit-ins nationwide on Friday, Sanders joined climate strikers near the Capitol Building in Des Moines to bolster their demand for bold action on the crisis that is impacting people around the world, including rural regions in the United States.

"You're seeing planting seasons decline, and harvests decline, because farmers cannot grow crops when their fields are underwater or when they have drought," Sanders told the crowd of young people and allies.

"We're looking not only in Iowa, not only in the Midwest, not only in America—we're looking all over the world about a serious crisis in food production," Sanders said. "That's the bad news. But here is the good news. If we have the courage to take on the fossil fuel industry and other special interests, if we have the courage to pass a Green New Deal, we can create up to 20 million good-paying jobs transforming our energy system."

Along with local youth climate leaders, Sanders addressed the need for a broad and bold vision to address the emergency and applauded those around the globe rising to demand action.

"Young people all over the world, not just here in Iowa or in the United States, but all over the world are telling their leaders, 'Hey, we want a planet that we can grow up in and have kids in that is healthy and inhabitable,'" Sanders said at the Des Moines event. "When that global movement spreads, maybe, just maybe, we can tell world leaders all over the planet that instead of spending $1.8 trillion a year on weapons of destruction designed to kill each other, maybe we can pool our resources and combat our common enemy which is climate change."

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I'm proud to stand with young people in Iowa and around the world today in their climate strikes. This is about the future of the planet and we won't accept a middle ground approach. We need a Green New Deal. https://t.co/BsX9K7NHx2 — Bernie Sanders (@BernieSanders) December 6, 2019

Later on Friday, several leaders of the U.S. Youth Climate Strike group—namely co-founder and partnerships director Isra Hirsi, executive director Felíquan Charlemagne, political director Daylon Prochaska, and creative director Pujan Patel—all stepped forward to officially endorse Sanders for president.

"Historically, movements have had young people at the forefront and the climate movement is no exception," Hirsi said. "Bernie has been there since day one fighting alongside all the young people across the country."

Sanders' plan for a Green New Deal, added Charlemagne, "is the only plan that addresses the climate crisis to the scale it needs to be addressed. It is the only plan that sets our goals to 2030. It is the only plan that has such a consideration of climate migrants, the only plan that has such a consideration of climate justice. It's the only plan that can save our planet."

Sanders' Green New Deal has been heralded by climate experts as the gold standard among those currently running for president. With a goal of reaching 100 percent renewable energy for electricity and transportation by no later than 2030, his campaign says the proposal aims to ensure "justice for frontline communities" and vows to build on the organizing and demands set forth by climate justice movement that gives priority to young people, workers, indigenous people, and communities of color.

"When Bernie talks about this being a global crisis where we need to come together as one planet, this is what he means," Pujan said. "A grassroots movement where the working class stands up and tells the government that we have a say and that we deserve to survive."

Meanwhile, Sunrise activists who have championed Sanders and other lawmakers leading the charge in Congress, but said those standing in the way—whether President Donald Trump, other Republicans, or Democrats still downplaying the need for urgent action—can no longer be tolerated.

"We need a Green New Deal. All these other watered down ideas are a waste of time," said Wally Mazon, 25, a Sunrise organizer in Iowa. "When my people from the LGBTQ community are under attack, when people can't get healthcare, when people can't vote, I can no longer live in a world of apathy on the part of our government. The Green New Deal is about fighting for the world we should be living in, but was stolen from us by a handful of greedy people."

According to Sunrise statement early Friday afternoon, sit-ins were underway at the offices of Rep. Axne in Iowa, Gov. Charlie Baker in Massachusetts, Rep. Chris Pappas in New Hampshire, and the Asheville City Council in North Carolina, with more to come throughout the day. Young people also die-ins and banner drops in major cities including Chicago, San Francisco, and Houston.

The view from the state house where hundreds of young people have gathered in support of those risking arrest. @sunriseboston @sunrisemvmt pic.twitter.com/YAPvfF3kiK— Varshini Prakash (@VarshPrakash) December 6, 2019 "We must take drastic action right now if we are to save our planet. The massive change we need will not happen overnight. Rather, we must mobilize like never before to make it happen." - @nainagradin from @sunriseannarbor on why she's striking todayhttps://t.co/3JsKg2k6UO — Sunrise Movement (@sunrisemvmt) December 6, 2019 Hundreds of young people in Springfield today demanding that Rep. Richard Neal stop protecting the fossil fuel industry and support the Green New Deal #GND #YouthClimateStrike pic.twitter.com/a4qPEa2Cas — logan malik (@logandmalik) December 6, 2019

With the United Nations climate talks at the COP 25 conference taking place in Madrid, Spain this week and next, there were massive Fridays for Future protests across Europe and elsewhere. In Madrid itself, an estimated half million people rallied in the streets.

In a tweet on Friday, Sunrise's executive director Varshini Prakash, said, "Big Oil wants us to believe we're too young, that we can't win, that we're powerless. Because for every person disillusioned, despairing and in denial that's another dollar in their pockets. We won't give that to them. We are rising. The young people will win a Green New Deal."