Climate change is “undoubtedly responsible” for the intensity of the heatwave sweeping across Western Europe, according to a new study published today by the World Weather Attribution (WWA) network of scientists. Researchers conclude that such an event would have been virtually impossible just 50 years ago.

The exceptionally high daytime and nighttime temperatures recorded during the current heatwave would have been “essentially impossible” to occur at the same time of year in 1976—another year remembered for a major European heatwave—according to the researchers, who examine the role of human-induced climate change in extreme weather events.

The scientists estimate that a comparable heatwave in 1976 would have been accompanied by temperatures 3.5°C lower during the day and 2.4°C lower at night.

“We concluded that over the past 50 years, during which global temperatures have risen by about 1.1°C, the likelihood of a heatwave like this has changed dramatically,” said Theodor Kipping of Imperial College London, one of the study’s authors.

“This heatwave simply could not have occurred in June without climate change,” he added.

Western Europe has been experiencing extreme temperatures for more than a week due to a massive plume of hot air moving north from Africa, trapped by a high-pressure system at altitude.

“This weather pattern is not particularly unusual, but the temperatures certainly are—or at least they were before human-caused climate change,” said Friederike Otto, also of Imperial College London.

“Unpleasant and Dangerous”

Human-induced climate change is primarily driven by the extensive use of fossil fuels—including coal, oil and natural gas—and, to a lesser extent, by deforestation.

For the study, researchers based across several European countries compared current weather observations and forecasts with historical climate data from 2003 and 1976.

Although the report was released rapidly and has not yet undergone peer review, as is customary for scientific publications, the authors emphasized that the methodology used has already been extensively validated by the scientific community.

According to the analysis, extremely warm nights are now 100 times more likely than they were during the 2003 European heatwave, while the probability of daytime temperature peaks has increased by roughly tenfold.

The researchers also ruled out El Niño as a contributing factor to the current heatwave.

“The heat stress, which combines high temperatures and humidity, makes this heatwave particularly unpleasant and dangerous,” Otto said.

According to the report, nearly 45% of the 854 cities analyzed across 30 European countries have already broken—or are on track to break—their all-time records for heat stress.

The WWA study notes that the full health impacts of the current heatwave are only beginning to emerge. It points to previous scientific research estimating that more than 60,000 people died from heat-related causes during the series of heatwaves that struck Europe in the summer of 2022.

“We are not doing enough to slow the pace of global warming,” said Clare Barnes, a researcher at Imperial College London. “As warming continues, we should expect temperature records to be broken more and more frequently.”

Europe remains the fastest-warming continent on Earth, the researchers concluded.