Extreme weather reached alarming levels in 2024, with record heat driving heatwaves, droughts, storms, and floods that displaced millions and caused thousands of deaths.

Last year’s events, fuelled by 1.3°C of human-induced warming, underscore the urgency of transitioning away from fossil fuels, said World Weather Attribution (WWA) and Climate Central researchers.

At least 3,700 lives were lost, and millions were displaced in 26 major weather disasters linked to climate change. These represent a fraction of 219 impactful events recorded in 2024. The true death toll likely reaches tens or hundreds of thousands globally.

New analysis by Climate Central shows climate change added 41 more days of dangerous heat worldwide in 2024. Small island and developing nations, particularly vulnerable to extreme heat, faced the highest impact. Such events remain underreported despite their widespread consequences.

El Niño played a role in early 2024’s extremes, but climate change had a greater influence, as seen in the Amazon’s historic drought. As the planet warms, climate change increasingly overshadows natural weather drivers.

“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,” said Friederike Otto, of WWA and a climate scientist at Imperial College, at a media briefing.

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

“People don’t have to die in heat waves. But if we can’t communicate convincingly, ‘but actually a lot of people are dying,’ it’s much harder to raise this awareness,” Otto added. “Heat waves are by far the deadliest extreme event, and they are the extreme events where climate change is a real game changer.”

Last year was likely the hottest ever recorded, say experts.

Record global heat contributed to unprecedented rainfall and flooding across regions like Dubai, Kathmandu, and the US’s Southern Appalachians. Of 16 studied floods, 15 were intensified by climate change. Heavier rainfall, driven by warming, overwhelmed warning systems and defences, especially in Sudan and Brazil.

Severe droughts and wildfires devastated the Amazon and Pantanal Wetland, causing biodiversity loss and threatening the Amazon's role as a carbon sink. Preserving these ecosystems is critical for global climate stability.

Warmer seas and air amplified storms like Hurricane Helene and Typhoon Gaemi.

Climate studies show most Atlantic hurricanes between 2019–2023 were stronger due to human-induced climate heating, with intensifying typhoon risks in the Philippines as global temperatures rise.