The backdrop: The Friday for Future protests began in 2018 when Swedish teen climate activist Greta Thunberg went on strike from school on Fridays. Since then, Thunberg has become the face of youth climate protests and advocacy.

In New York City: Thunberg led the protests. The main protests were scheduled for noon, but protesters gathered early, per the New York Times. Leading up to the protests, New York City announced its 1.1 million students are allowed to skip school to participate.

Students walk out of school to take part in a march to demand action on the global climate crisis in New York City. Photo: Spencer Platt/Getty Images

In Germany: At least 500 protests are planned across Germany as German Chancellor Angela Merkel prepares to unveil a new climate protection package. Her government has been under increasing pressure to take action after a summer of heatwaves, per the Post.

Participants in the Fridays For Future movement protest during a nationwide climate change action day in front of the Brandenburg Gate in Berlin, Germany Photo: Carsten Koall/Getty Images

In Australia: The first wave of demonstrations started in Australia, with more than 300,000 protesters marching across more than 110 towns and cities, according to the School Strike 4 Climate. Protesters demanded no fossil fuels and 100% renewable energy.

Student demonstrators and thousands of environmentalists gather holding banners on a demonstration during Climate Strike in Melbourne, Australia. Photo: Recep Sakar/Anadolu Agency/Getty Images

In Indonesia: Students and protesters gathered to call for action against the fires that burned through nearly 800,000 acres around the country, per the Post. The smoke is causing health problems, endangering wildlife and is spreading to nearby Malaysia.

Young protesters are seen holding a climate emergency banner and placards during a "Fridays for Future" demonstration in Jakarta, Indonesia. Photo: Afriadi Hikmal/NurPhoto/Getty Images

In the United Kingdom: Thousands of protesters and students gathered across the country. Students staged a "die-in" in Belfast, Ireland, per BBC. Labour Party leader Jeremy Corbyn plans to speak with protesters in Westminster.

Climate activists block Whitehall during a sit-in as thousands of students, school children and workers turn out for a Global Climate Strike in central London. Photo: Amer Ghazzal/Barcroft Media/Getty Images

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