An anonymous reader quotes a report from the Washington Post: Oil and gas companies are facing hundreds of lawsuits around the world testing whether they can be held responsible for their role in causing climate change. Now, two scientists say they’ve built a tool that can calculate how much damage each company’s planet-warming pollution has caused — and how much money they could be forced to pay if they’re successfully sued. Collectively, greenhouse emissions from 111 fossil fuel companies caused the world $28 trillion in damage from extreme heat from 1991 to 2020, according to a paper published Wednesday in Nature. The new analysis could fuel an emerging legal fight.The authors, Dartmouth associate professor Justin Mankin and Chris Callahan, a postdoctoral researcher at Stanford University, say their model can determine a specific company’s share of responsibility over any time period. […]
Callahan and Mankin’s work combines all of these steps — estimating a company’s historical emissions, figuring out how much those emissions contributed to climate change and calculating how much economic damage climate change has caused — into one “end-to-end” model that links one polluter’s emissions to a dollar amount of economic damage from extreme heat. By their calculation, Saudi Aramco is on the hook for $2.05 trillion in economic losses from extreme heat from 1991 to 2020. Russia’s Gazprom is responsible for $2 trillion, Chevron for $1.98 trillion, ExxonMobil for $1.91 trillion and BP for $1.45 trillion. Industry groups and companies tend to object to the methodologies of attribution science. They could seek to contest the assumptions that went into each step of Mankin and Callahan’s model.
Indeed, every step in that process introduces some room for error, and stringing together all of those steps compounds the uncertainty in the model, according to Delta Merner, lead scientist at theScience Hub for Climate Litigation, which connects scientists and lawyers bringing climate lawsuits. She also mentioned that the researchers relied on a commonly used but simplified climate model known as the Finite Amplitude Impulse Response (FAIR) model. “It is robust for the purpose of what the study is doing,” Merner said, “but these models do make assumptions about climate sensitivity, about carbon cycle behavior, energy balance, and all of the simplifications in there do introduce some uncertainty.” The exact dollar figures in the paper aren’t intended as gospel. But outside scientists said Mankin and Callahan use well-established, peer-reviewed datasets and climate models for every step in their process, and they are transparent about the uncertainty in the numbers.