Natural hazard information and migration across cities:Evidence from the anticipated Nankai Trough earthquake

The Nankai Trough and its underlying fault are the major source of the future devastating earthquake, the Nankai Trough earthquake. The Central Disaster Management Council, which is a governmental committee for policy planning on disaster management, released the latest report on the predicted damage from the Nankai Trough earthquake in 2012. The new report estimated the maximum possible seismic movements and tsunami height for each municipality, which were updated from the previous ones released in 2003. We examine the causal impact of the municipality-level predicted seismic movements and tsunami heights on the net migration across municipalities. The Difference-in-Differences (DID) estimates suggest that the predicted tsunami height is significantly negatively associated with the municipality’s net migration rate. Further empirical analysis shows that the predicted tsunami height has a prolonged negative impact on the in-migration into the municipality, whereas it has only a short-term positive impact on the out-migration. Our empirical findings suggest that, after the dissemination of tsunami predictions, people tend to choose less risky locations, rather than engaging in other disaster-prevention activities. In addition, we found that the negative impact of tsunami heights on the in-migration is weaker in municipalities where public facilities that can serve as disaster relief or evacuation center are concentrated in the densely inhabited district.