Unveiling the Unseen Illness

Abstract

We utilize region-day variation in actual vs. forecasted weather conditions (i.e. forecasting errors) to comprehensively investigate the effects of the first public warning system for extreme heat events on behavioral and health outcomes in Japan. We find that heat alerts led to a 16% increase in ambulance-related hospital visits. An analysis of mechanisms suggests this is primarily driven by increased awareness and thus reporting of heat strokes that would otherwise have gone undetected, as opposed to substitution in health diagnoses. We further document evidence of avoidance behaviors (e.g. electricity usage).