Overview

• Two peer-reviewed Nature studies published Sept. 18 find roughly 40,000 U.S. deaths a year from wildfire-smoke PM2.5 today and project about 70,000 annually by the 2050s under high emissions, with a companion global analysis forecasting up to 1.4 million deaths per year by century’s end.
• Monetized damages from smoke-related mortality in the U.S. could reach about $608 billion annually by 2050, exceeding current estimates for all other quantified climate impacts combined.
• Exposure is nationwide due to long-range transport, with the largest increases projected in California—including more than 1,100 additional deaths a year in Los Angeles County—and substantial rises in New York, Washington, Texas, and Pennsylvania.
• The U.S. study links climate to fire activity, smoke concentrations, and mortality using satellite-based PM2.5 and county death records from 2006–2019/2011–2020, though it omits some recent extreme events (2020 West Coast, 2023 Canadian fires) that could mean underestimates in some regions.
• Authors recommend mitigation and adaptation—cutting emissions, expanding prescribed burns and fuel treatments, improving indoor filtration and public-health protections—as the findings factor into regulatory debates including the EPA proposal to rescind the greenhouse-gas endangerment finding with comments open until Sept. 22.