However, rapidly cutting global emissions to keep global heating to 1.5C would almost halve the heatwaves today’s children will experience, while keeping under 2C would reduce the number by a quarter.

A vital task of the UN’s Cop26 climate summit in Glasgow in November is to deliver pledges of bigger emissions cuts from the most polluting countries and climate justice will be an important element of the negotiations. Developing countries, and the youth strike protesters who have taken to the streets around the world, point out that those who did least to cause the climate crisis are suffering the most.

“Our results highlight a severe threat to the safety of young generations and call for drastic emission reductions to safeguard their future,” said Prof Wim Thiery, at Vrije Universiteit Brussel in Belgium and who led the research. He said people under 40 today were set to live “unprecedented” lives, ie suffering heatwaves, droughts, floods and crop failures that would have been virtually impossible – 0.01% chance – without global heating.

Dr Katja Frieler, at the Potsdam Institute for Climate Impact Research in Germany and part of the study team, said: “The good news is we can take much of the climate burden from our children’s shoulders if we limit warming to 1.5C by phasing out fossil fuel use. This is a huge opportunity.”

Leo Hickman, editor of Carbon Brief, said: “These new findings reinforce our 2019 analysis which showed that today’s children will need to emit eight times less CO2 over the course of their lifetime than their grandparents, if global warming is to be kept below 1.5C. Climate change is already exacerbating many injustices, but the intergenerational injustice of climate change is particularly stark.”

The research, published in the journal Science, combined extreme event projections from sophisticated computer climate models, detailed population and life expectancy data, and global temperature trajectories from the Intergovernmental Panel on Climate Change.

The scientists said the increases in climate impacts calculated for today’s young people were likely to be underestimates, as multiple extremes within a year had to be grouped together and the greater intensity of events was not accounted for.

There was significant regional variation in the results. For example, the 53 million children born in Europe and central Asia between 2016 and 2020 will experience about four times more extreme events in their lifetimes under current emissions pledges, but the 172 million children of the same age in sub-Saharan Africa face 5.7 times more extreme events.

“​​This highlights a disproportionate climate change burden for young generations in the global south,” the researchers said.

Dohyeon Kim, an activist from South Korea who took part in the global climate strike on Friday, said: “Countries of the global north need to push governments to put justice and equity at the heart of climate action, both in terms of climate [aid] and setting more ambitious pledges that take into consideration historical responsibilities.”

The analysis found that only those aged under 40 years today will live to see the consequences of the choices made on emissions cuts. Those who are older will have died before the impacts of those choices become apparent in the world.