A new study published in the scientific journal Nature confirms that 55 heatwaves that occurred between 2000 and 2023 would not have happened without the climate change caused by humans.
The research analyzed 213 extreme events recorded in the International Disaster Database EM-DAT, and attributed their origin to the polluting emissions from 180 major producers of cement, oil, and gas.
Concentration of responsibility: few actors, great impact
57% of CO₂ emitted since 1850 comes from a small group of companies and countries.
The study identified publicly traded companies, state-owned entities, and fossil fuel-producing countries responsible for over half of historical carbon dioxide emissions.
According to Sonia Seneviratne, a climatologist at ETH Zurich, this demonstrates that a limited number of actors have caused a disproportionate fraction of global climate damage.
“Many of these heatwaves had very serious consequences,” said Seneviratne, citing the series of extreme events that affected Europe in 2022 and caused tens of thousands of deaths.
Attribution science: tools to understand and act
Climate models allow linking extreme events to specific emissions.
The research is based on climate attribution science, a discipline established for two decades that uses computer models and historical weather data to determine the degree of human influence on extreme phenomena.
The novelty of this study is that it quantifies the responsibility of specific industrial sectors, such as cement and fossil fuels, in the occurrence of heatwaves.
Legal implications and public policies
Activists and governments seek to hold companies accountable for climate damages.
The results of the study could have legal relevance, in a context where dozens of lawsuits have been filed against fossil fuel companies by activists, state governments, and affected communities. States like Vermont and New York have already passed laws seeking to assign legal and economic responsibility to these companies for their emissions and impacts.
“For a long time, it was said that individual contributions were too diffuse to be linked to specific damages. This science shows that is no longer true,” stated Chris Callahan, a climatologist at Indiana University.
Climate justice and reparations: Who pays for the losses?
Scientific attribution opens the debate on compensations and responsibilities.
For Justin Mankin, a researcher at Dartmouth College, the study provides a clear vision of the origins of heatwaves and raises urgent questions about who should bear the costs of damages.
In a world increasingly affected by extreme events, climate justice demands identifying responsible parties and ensuring mechanisms for reparation.
