1.5 billion children could be exposed to extreme heat by 2100, climate study says

What you probably already know: The 10 hottest years in nearly 200 years of record-keeping all occurred within the last decade and 2024 was the warmest year to date, with Earth’s surface reaching more than 1.5 degrees Celsius above the pre-industrial average for the first time. A new climate study breaks down the impact of a rapidly warming planet on children, who are set to experience more climate extremes than any generation that came before.

Why? If the planet’s temperature rises by 3.5 degrees Celsius by 2100, 92% of children born in 2020 (that’s 111 million children) will experience “unprecedented lifetime exposure” to heatwaves, according to the study led by Vrije Universiteit Brussel scientists. When the camera zooms out to include all children currently between the ages of 5 and 18, the number rises to 1.5 billion. However, if global warming can be limited to 1.5 degrees Celsius, the study found that about half of those born in 2020 (or 855 million children currently aged 5-18) will endure unprecedented heatwaves, compared to 16% of people born in 1960. Extreme heatwaves are expected to impact the largest share of the Earth’s population, followed by crop failures, river floods, droughts, wildfires, and tropical storms.

"In this new study, living an unprecedented life means that without climate change, one would have less than a 1-in-10,000 chance of experiencing that many climate extremes across one's lifetime," said Dr. Luke Grant, lead author and climate scientist at the VUB and Environment and Climate Change Canada. "This is a stringent threshold that identifies populations facing climate extremes far beyond what could be expected without man-made climate change."

What it means: Children in tropical areas will bear the brunt of climate change impacts under and a child’s socioeconomic status also determines the extent to which they’ll experience climate change. The study suggests 95% of the most vulnerable children born in 2020 will live through unprecedented extremes because they have limited resources and ways to adapt, compared to 78% of their least vulnerable counterparts. For example, children who live in areas impacted by sea level rise often lack the resources necessary to leave those areas for safer ground.

What happens now? Scientists predict the Earth’s surface will climb to 2.7 degrees Celsius above the pre-industrial era average within the current century if nothing changes. The Paris Agreement, a pact signed by 195 countries and the European Union, aims to limit the temperature increase to 1.5 degrees. While the Earth temporarily surpassed the target last year, the agreement hasn’t failed yet. For that, temperatures would need to hold steady over a longer period. But scientists say that reducing the impacts of a warming planet — particularly for young people who will inherit the problem — demands urgent action. The study suggests that meeting the Paris Agreement’s target could spare 49 million children from unprecedented lifetime exposure to dangerous heat. Similar research released by Save the Children concludes that nearly a third of all 5-year-olds today would be protected from the same risk if global warming is limited to 1.5 degrees by 2100.

"Across the world, children are forced to bear the brunt of a crisis they are not responsible for,” said Inger Ashing, CEO of Save the Children International. “Dangerous heat that puts their health and learning at risk; cyclones that batter their homes and schools; creeping droughts that shrivel up crops and shrink what's on their plates. Amid this daily drumbeat of disasters, children plead with us not to switch off. This new research shows there is still hope, but only if we act urgently and ambitiously to rapidly limit warming temperatures to 1.5 °C, and truly put children front and centre of our response to climate change."