Does Social Capital Mitigate Natural Disaster Risk?: Evidence from Voluntary Disaster Prevention Organizations in Japan

As climate change accelerates, the frequency and intensity of natural disasters, particularly meteorological ones, have increased.While physical capital plays a critical role in mitigating damage, it alone cannot fully address disaster risk, and recent studies find the importance of social capital.However, existing empirical studies often focus on specific disasters or regions, and national-level analyses typically rely on aggregated data that obscure local dynamics.To advance our understanding of social capital's role in disaster resilience, we constructed a novel municipality-level panel dataset that includes both natural disaster and social capital indicators across Japan.Social capital is measured by the number and annual activities of voluntary disaster prevention organizations, that is, community-led groups that conduct disaster drills and other prevention activities.Our dataset covers the years from 2014 to 2023.Using fixed-effects regression models, we find that, controlling for the severity of natural hazards, these organizations' greater presence and activity level are significantly associated with fewer casualties during storms and floods.Such a relationship is only weakly observed for earthquakes.These findings suggest that social capital is particularly important in mitigating the impacts of more predictable disasters, where community-led evacuation and coordination efforts are more feasible.