‘Almost impossible’: Another one of the hottest years on record brings previously unimaginable frequency of heat waves
It was the first time that the three-year temperature average broke through the threshold set in the 2015 Paris Agreement since preindustrial times.
Climate change worsened by human behavior made 2025 one of the three hottest years on record, scientists said.
It was also the first time that the three-year temperature average broke through the threshold set in the 2015 Paris Agreement of limiting warming to no more than 1.5 degrees Celsius (2.7 Fahrenheit) since preindustrial times. Experts say that keeping the Earth below that limit could save lives and prevent catastrophic environmental destruction around the globe.
The analysis from World Weather Attribution researchers, released Tuesday in Europe, came after a year when people around the world were slammed by the dangerous extremes brought on by a warming planet.
Temperatures remained high despite the presence of a La Nina, the occasional natural cooling of Pacific Ocean waters that influences weather worldwide. Researchers cited the continued burning of fossil fuels — oil, gas and coal — that send planet-warming greenhouse gases into the atmosphere.
“If we don’t stop burning fossil fuels very, very, quickly, very soon, it will be very hard to keep that goal” of warming, Friederike Otto, co-founder of World Weather Attribution and an Imperial College London climate scientist, told The Associated Press. “The science is increasingly clear.”
Extremes in 2025
Extreme weather events kill thousands of people and cost billions of dollars in damage annually.
WWA scientists identified 157 extreme weather events as most severe in 2025, meaning they met criteria such as causing more than 100 deaths, affecting more than half an area’s population or having a state of emergency declared. Of those, they closely analyzed 22.
That included dangerous heat waves, which the WWA said were the world’s deadliest extreme weather events in 2025. The researchers said some of the heat waves they studied in 2025 were 10 times more likely than they would have been a decade ago due to climate change.
“The heat waves we have observed this year are quite common events in our climate today, but they would have been almost impossible to occur without human-induced climate change,” Otto said. “It makes a huge difference.”
Meanwhile, prolonged drought contributed to wildfires that scorched Greece and Turkey. killed dozens of people and left many more missing. Super Typhoon Fung-wong , forcing more than a million people to evacuate. battered India with floods and landslides.