Students hold signs during a rally for global climate strike for future in Seoul, South Korea, March 15, 2019. VOA
But scientists have backed the protests, with thousands signing petitions in support of the students in Britain, Finland and Germany.
"We are the professionals and we're saying the young generation is right," said Volker Quaschning, a professor of engineering at Berlin's University of Applied Sciences.
"We should be incredibly grateful and appreciative of their bravery," said Quaschning, one of more than 23,000 German-speaking scientists to sign a letter of support this week. "Because in a sense, it's incredibly brave not to go to school for once."
Scientists have warned for decades that current levels of greenhouse gas emissions are unsustainable, so far with little effect. In 2015, world leaders agreed in Paris to a goal of keeping the Earth's global temperature rise by the end of the century well below 2 degrees Celsius (3.6 degrees Fahrenheit).
Yet at present, the world is on track for an increase of 4 degrees Celsius, which experts say would have far-reaching consequences for life on the planet.
"As a doctor, I can say it makes a big difference whether you've got a fever of 41 degrees Celsius (105.8 Fahrenheit) or 43 C (109.4 F)," said Eckart von Hirschhausen, a German scientist who signed the call supporting striking students. "One of those is compatible with life, the other isn't."
Other action
German Chancellor Angela Merkel and French President Emmanuel Macron have publicly welcomed the student protests, even as their policies have been criticized as too limited by environmental activists.
In France, activist groups launched legal action this week for failing to do enough to fight climate change, citing a similar successful effort in the Netherlands.
