Hot Days, Unsafe Schools? The Impact of Heat on School Shootings

Using data on school shooting incidents in U.S. K--12 schools from 1981 to 2022, we estimate the causal effects of high temperatures on school shootings and assess the implications of climate change. We find that days with maximum temperatures exceeding 90$^\circ$F lead to a 80\% increase in school shootings relative to days below 70$^\circ$F. Consistent with theories linking heat exposure to aggression, high temperatures increase homicidal and threat-related shootings but have no effect on accidental or suicidal shootings. Heat-induced shootings occur disproportionately during periods of greater student mobility and reduced supervision, including before and after school hours and lunch periods. Higher temperatures increase shootings involving both student and non-student perpetrators. We project that climate change will increase homicidal and threat-related school shootings in the U.S. by 8\% under SSP2--4.5 (moderate emissions) and by 14\% under SSP5--8.5 (high emissions) by 2091--2100, corresponding to approximately 23 and 39 additional shootings per decade, respectively. The present discounted value of the resulting social costs is \$343 million and \$592 million (2025 dollars), respectively.