Environmental migration as short‐ or long‐term differences from a trend: A case study of Hurricanes Katrina and Rita effects on out‐migration in the Gulf of Mexico

Abstract

AbstractAn environmental event that damages housing and the built environment may result in either a short‐ or long‐term out‐migration response, depending on residents' recovery decisions and hazard tolerance. If residents move only in the immediate disaster aftermath, then out‐migration will be elevated only in the short‐term. However, if disasters increase residents' concerns about future risk, heighten vulnerability, or harm the local economy, then out‐migration may be elevated for years after an event. The substantive aim of this research brief is to evaluate hypotheses about short‐ and long‐term out‐migration responses to the highly destructive 2005 hurricane season in the Gulf of Mexico. The methodological aim is to demonstrate a difference‐in‐differences (DID) approach analysing time series data from Gulf Coast counties to compare short‐ and long‐differences in out‐migration probabilities in the treatment and control counties. We find a large short‐term out‐migration response and a smaller sustained increase for the disaster‐affected coastal counties.