Attributing human mortality from fire PM2.5 to climate change

Abstract Wildfires affect human health by emitting hazardous air pollutants. The contribution of climate change to global fire-induced health impacts has not been quantified so far. Here, we used three fire-vegetation models in combination with a chemical transport model and health risk assessment framework to attribute global human mortality from fire fine particulate matter (PM 2.5 ) emissions to climate change. Among the total 31,934 (1960s) –75,870 (2010s) annual fire PM 2.5 mortalities, climate change generated excess annual deaths from 819 (1960s) to 5,541 (2010s). The influence of climate change on fire mortality is strongest in South America, southern Australia, and Europe, coinciding with a significant decrease in relative humidity. In other regions, such as South Asia, increasing relative humidity has gradually decreased fire mortality. Our study highlights that climate change already contributed to fire mortality and our findings will help public health authorities to better predict and manage fire mortality.