For many children around the world, school is out for summer—but that hasn't stopped youth activists from taking to the streets to demand governments pursue bold solutions to battle the global climate emergency.

"The climate crisis doesn't go on summer holiday, and neither will we. We go on," tweeted Greta Thunberg, the Swedish teenager who sparked the global climate student strike movement by protesting alone outside her country's parliament last year.

School strike week 46. The climate crisis doesn’t go on summer holiday, and neither will we. We go on.#fridaysforfuture #schoolstrike4climate #climatestrike pic.twitter.com/JGdvAVaSjW — Greta Thunberg (@GretaThunberg) July 5, 2019

As experts continue to sound the alarm over record-breaking temperatures worldwide, youth strikers from across the globe posted photos of their demonstrations Friday on social media with the hashtags #FridaysForFuture, #SchoolStrike4Climate, and #ClimateStrike.

"As days passes by, so does our future draw nearer. It doesn't matter the course you study nor your age, we need you to join climate justice," said organizer Oladosu Adenike, sharing a photo of schoolchildren in Nigeria.

#FridaysForFuture#ClimateStrike in Nigeria.

As days passes by, so does our future draw nearer.

It doesn't matter the course you study nor your age, we need you to join climate justice. pic.twitter.com/n5ixV7aQCT — Oladosu Adenike (@the_ecofeminist) July 5, 2019

Youth in Dhaka, Bangladesh held signs that read "save the Earth, save yourself" and "come foward to save our tomorrow."

Tweeting from Turkey, 11-year-old Deniz Çevikus reported from a popular spot beside the Bosphorus that "people are interested but shy."

Climate Strike Week 15. Moving into busier and busier locations every week. Today's strike is at Ortaköy, a very popular spot on the European side of the Bosphorus. People are interested but shy. @GretaThunberg @FridaysTurkey #schoolstrike4climate #climatestrike #fridaysforfuture pic.twitter.com/Y9l66gKy0b — Deniz Çevikus (@CevikusDeniz) July 5, 2019

Others shared photos from Germany, Uganda, and Switzerland:

The climate action group Extinction Rebellion tweeted Friday that "the millions of children striking from school will become millions of adults striking from work if our governments continue to fail to #ActNow on the climate and ecological emergencies."

The millions of children striking from school will become millions of adults striking from work if our governments continue to fail to #ActNow on the climate and ecological emergencies.#FridaysForFuturehttps://t.co/5HQkqqOel4#RebelForLifehttps://t.co/PzxBohj9iu pic.twitter.com/SU7iqef4cT — Extinction Rebellion (@ExtinctionR) July 5, 2019

In May, as Common Dreams reported, "well-known adult climate activists answered a call to action from school strikers with a pledge to join global protests." The adults announced in an op-ed that on Sept. 20, "we're walking out of our workplaces and homes to spend the day demanding action on the climate crisis, the greatest existential threat that all of us face."

Penn State University climate scientist Michael E. Mann was among those who signed on to the op-ed. In an interview with Hill.TV that aired earlier this week, Mann said that to combat the climate crisis, "we do need a world-war type mobilization and that means putting in place incentives to move our economy as quickly as we can away from fossil fuels to renewable energy."

"There's a legitimate policy debate to be had about how we do that, but there isn't a legitimate debate to be had anymore about the need to do that," added Mann, who also argued that electing any Democratic 2020 candidate would be better than re-electing President Donald Trump.

"There's a world of difference between where the Trump administration is and all of the Democrats, and I would hate to see too much infighting at this point," Mann said. "Let's make sure that we elect a president who's not going to continue to lead us backward and defy the rest of the world as we try to act on this existential threat."

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