World endured extra 41 days of dangerous heat in 2024

People around the world suffered an average of 41 extra days of dangerous heat this year because of human-caused climate change, according to a group of scientists who also said much of the world’s damaging weather worsened throughout 2024.

The analysis from researchers at World Weather Attribution and Climate Central comes at the end of a year that shattered climate records as heat across the globe made 2024 likely to be its hottest ever measured and few countries were spared fatal weather events.

“The finding is devastating but utterly unsurprising: Climate change did play a role, and often a major role in most of the events we studied, making heat, droughts, tropical cyclones and heavy rainfall more likely and more intense across the world, destroying lives and livelihoods of millions and often uncounted numbers of people,” Friederike Otto, the organisation’s lead researcher said.

“As long as the world keeps burning fossil fuels, this will only get worse.”

Northern California and Death Valley baked. Sizzling daytime temperatures scorched Mexico and Central America. Heat endangered already vulnerable children in West Africa. Skyrocketing southern European temperatures forced Greece to close the Acropolis.

In South and Southeast Asian countries, heat forced school closures. Earth experienced some of the hottest days ever measured and its hottest-yet summer, with a 13-month heat streak.

The team of volunteer international scientists compared daily temperatures around the globe in 2024 to the temperatures that would have been expected in a world without climate change. The results are not yet peer-reviewed, but researchers use peer-reviewed methods.

Some areas saw 150 days or more of extreme heat due to climate change.

“The poorest, least developed countries on the planet are the places that are experiencing even higher numbers,” said Kristina Dahl, vice president of climate science at Climate Central.

“Heat waves are by far the deadliest extreme event, and they are the extreme events where climate change is a real game changer,” Otto said.

The researchers closely examined 29 extreme weather events this year that killed at least 3,700 people and displaced millions, and found that 26 of them had clear links to climate change.

The El Niño weather pattern, which naturally warms the Pacific Ocean and changes weather around the world, made some of this weather more likely earlier in the year. But the researchers said most of their studies found that climate change played a bigger role than that phenomenon in fuelling 2024’s events.

Warm ocean waters and warmer air fuelled more destructive storms, according to the researchers, while temperatures led to many record-breaking downpours.

This year was a warning that the planet is getting dangerously close to the Paris Agreement’s 1.5 degrees Celsius warming limit compared to the pre-industrial average, according to the scientists. Earth is expected to soon edge past that threshold, although it’s not considered to have been breached until that warming is sustained over decades.

But the deaths and damages from extreme weather events aren’t inevitable, said Julie Arrighi, director of programs at the Red Cross Red Crescent Climate Centre and part of the research.

“Countries can reduce those impacts by preparing for climate change and adapting for climate change, and while the challenges faced by individual countries or systems or places vary around the world, we do see that every country has a role to play,” she said.