Human Activity Linked to 55 Heat Waves Over 25 Years

Tue Sep 23 2025 10:52:10 GMT+0300 (Eastern European Summer Time)

A recent study has revealed that 55 of the 213 heat waves analyzed from 2000 to 2023 would not have occurred without human-induced climate change, primarily driven by emissions from major fossil fuel and cement producers.

The study, published in the journal Nature, analyzed 213 heat waves and concluded that human-induced climate change has significantly increased their likelihood. It found that 55 of these heat waves experienced a 10,000-fold increase in probability since the industrialization era, emphasizing the responsibility of major global emitters of carbon dioxide, who account for 57% of emissions from 1850 to 2023. The research poses important implications for accountability within climate change-related legal actions against polluters.

Fifty-five heat waves over the past quarter-century would not have happened without human-caused climate change, according to a study published Wednesday.

Planet-warming emissions from 180 major cement, oil, and gas producers contributed significantly to all of the heat events considered in the study, which was published in the journal Nature and examined a set of 213 heat waves from 2000 to 2023. The polluters examined in the study include publicly traded and state-owned companies, as well as several countries where fossil fuel production data was available at the national level.

Collectively, these producers are responsible for 57% of all the carbon dioxide that was emitted from 1850 to 2023, the study found.

“It just shows that it’s not that many actors ... who are responsible for a very strong fraction of all emissions,” said Sonia Seneviratne, a climate professor at the Swiss university ETH Zurich who was one of the study’s contributors.

The set of heat waves in the study came from the EM-DAT International Disaster Database, which the researchers described as the most widely used global disaster repository. The Nature study examined all of the heat waves in the database from 2000 to 2023, except for a few that weren’t suitable for their analysis.

Global warming made all 213 of the heat waves examined more likely, the study found. Out of those, 55 were 10,000 times more likely to have happened than they would have been before industrialization began accelerating in the 1800s. The calculation is equivalent to saying those 55 heat waves “would have been virtually impossible” without human-caused climate change, the authors wrote.

“Many of these heat waves had very strong consequences,” said Seneviratne. She cited the series of heat waves that struck Europe in 2022 linked to tens of thousands of deaths as one of the events with particularly grave consequences.

Climate scientists can use complex computer programs and historic weather data to calculate the connection between extreme weather events and the planet-warming pollutants humans emit. Climate change attribution studies often focus on how climate change influenced a specific weather event. Still, this new study is unique as it focused on how cement and fossil fuel producers contributed to heat waves.

Scientists say the new study could be taken into consideration in legal cases. Globally, dozens of lawsuits have been filed against fossil fuel companies by climate activists, American state governments, and others seeking to hold the companies accountable for their role in climate change.