Students are seen during the global school strike for action on climate change outside New Zealand's parliament in Wellington, New Zealand, March 15, 2019. VOA
Protests in 100 countries
Friday's rallies are expected to be one of the biggest international actions yet. A website coordinating the protests lists events in more than 100 countries, from New Zealand to the United States.
Some politicians have criticized the students, suggesting they should be spending their time in school, not on the streets.
"One can't expect children and young people to see all of the global connections, what's technically reasonable and economically possible," said the head of Germany's pro-business Free Democratic Party, Christian Lindner. "That's a matter for professionals."
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 14,000 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."
Decades of warning
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."
Policies don't go far enough
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 .
In Germany, environmental groups and experts have attacked government plans to continue using coal and natural gas for decades to come. Activists say that countries like Germany should fully "decarbonize" by 2040, giving less-advanced nations a bit more time to wean themselves off fossil fuels while still meeting the Paris goal globally.
Other changes needed to curb greenhouse gas emissions include ramping up renewable energy production, reigning in over-consumption culture now spreading beyond the industrialized West and changing diets, experts say.
"The fight against climate change is going to be uncomfortable, in parts, and we need to have a societywide discussion about this," said Quaschning.
That conversation is likely to get louder, with several U.S. presidential hopefuls planning to campaign on climate change.
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Luisa Neubauer, one of the Berlin group organizing Fridays for Future, said politicians should take note of the young.
"For the European elections in May, we're urging everyone to think about whether they want to give their vote to a party that doesn't have a plan for the future and the climate," she said. (VOA)
