Jeff Wen , Marshall Burke

Wildfires have increased in frequency and severity over the past two decades, threatening to undo substantial air quality improvements. We investigate the effect of wildfire smoke exposure on learning outcomes across the US using standardized test scores from 2009-2016 for nearly 11,700 school districts and satellite-derived estimates of daily smoke exposure. Relative to a school year with no smoke, average cumulative smoke-attributable PM2.5 exposure during the school year (∼35 µg/m^3) reduces test scores by ∼ 0.15% of a standard deviation. These impacts are more pronounced among younger students and are observed across differing levels of economic disadvantage and racial-ethnic composition. Additionally, we project that smoke PM2.5 exposure in 2016 reduced discounted future earnings by nearly $1.7 billion ($111 per student). Roughly 80% of these costs are borne by disadvantaged districts. Our findings quantify a previously unaccounted for social cost of wildfire that is likely to worsen under a warming climate.