Striking school students will take action on Friday across many areas of Britain and large parts of the globe.
The UK Student Climate Network said, “We've got almost 100 strikes registered up and down the country. This is our chance to make sure this is THE climate election, but to do so we need everyone to turn out all around the country to make sure the politicians hear us loud and clear.”
In many areas student rallies will be joined by striking lecturers in the UCU union.
Their protests come days after new research suggested the world may already have crossed a series of climate tipping points.
Prof Tim Lenton at the University of Exeter, the lead author of the research report, said, “We might already have crossed the threshold for a cascade of interrelated tipping points. The simple version is the schoolkids striking for climate action are right—we are seeing potentially irreversible changes in the climate system under way, or very close.”
This risk is “an existential threat to civilisation” said leading scientists, meaning “we are in a state of planetary emergency”.
Tipping points are reached when particular impacts of global heating become unstoppable, such as the runaway loss of ice sheets or forests. In the past, extreme heating of 5 degree centigrade was thought necessary to pass tipping points, but the latest evidence suggests this could happen between 1C and 2C.
The planet has already heated by 1C and the temperature is certain to rise further, due to past emissions and because greenhouse gas levels are still rising.
The scientists further warn that one tipping point, such as the release of methane from thawing permafrost, may fuel others, leading to a cascade.
The researchers, writing in the journal Nature, acknowledge that the complex science of tipping points means great uncertainty remains.
But they say the potential damage from the tipping points is so big and the time to act so short, that “to err on the side of danger is not a responsible option”. They call for urgent international action.
The massive Greenland ice sheet was melting at an accelerating rate, the scientists said, while Arctic sea ice is shrinking fast. “Permafrost across the Arctic is beginning to irreversibly thaw and release carbon dioxide and methane,” they said.
The Gulf Stream current in the Atlantic, which warms Europe, has also slowed by 15 percent since the mid-20th century. “That is just about in the range of natural variability, but it is also hard to rule out that it is part of a longer downturn,” Lenton said.
The scientists report that 17 percent of the Amazon rainforest has been lost since 1970. The tipping point, where loss of forest leads to it drying out, could lie in the range 20 percent to 40 percent, they said.
In temperate forests, especially in North America, heating has triggered more fires and pest outbreaks, potentially turning some regions from a sink for carbon to a source. In the tropics, corals are predicted to be wiped out by 2C of heating.
The scale of the climate emergency demands mass revolt to force urgent action. The movement that has been swelled by the school students’ strikes and Extinction Rebellion events must not be centred on voting, or supporting for any political party.
March for planet, pay and pensions, Friday 29 November, 11am, Malet Street, London WC1E 7HY. Called by UCU London region and CWU London region