Nearly 83 million people could be killed by the end of the century if carbon emissions continue unchecked, according to a new study by Columbia University‚Äôs Earth Institute published in Nature Communications. The research builds on the “social cost of carbon” metric to account for excess heat deaths: the “mortality cost of carbon.” Lifetime emissions from 3.5 average Americans would kill one person. In contrast, lifetime per-capita emissions of 146.2 Nigerians would kill one person. The new research could change how economics calculate the social cost of carbon, which impacts policymaking.

Earlier this year the Biden administration set the cost at $51 a ton, but this new research suggests it should be set at around $258 per ton to reduce deaths from higher temperatures. Researcher Daniel Besser noted that the metric does not account for other climate-related deaths such as flooding, crop failure, and civil unrest, but said this metric is the best estimate based on current literature. (New York Times $, Bloomberg $, The Guardian, Axios)