Webinaire Junior sur l'économie des migrations. Adaptation in motion: Temporary migration under heat stress
Moumita Das
UC Santa Cruz
Résumé
The impact of climate-induced temporary migration remains largely unexplored. Yet, this flow is widespread in developing countries and also responds to warming. The distinction from permanent migration is critical: because temporary migrants are often under-counted and unaccounted for in local administrative planning, they generate a distinct externality through the systematic under-provisioning of public services. Using a large-scale panel survey in India, we find that a one-degree rise in mean daily temperature increases temporary out-migration rates by 2%-6%. To investigate spatial spillovers under widespread climate change, we develop a model with both migration channels where temperature affects productivity and the under-provisioning of public services degrades local amenities for everyone. We use this framework to quantify the welfare costs of restricting each migration channel and compare different policy responses under climate change. Under the IPCC SSP 5-8.5 climate change scenario, restricting temporary migration generates welfare costs larger than restricting permanent migration, demonstrating that temporary flows are a critical but overlooked adaptation mechanism. Remedying the under-provisioning of services for temporary migrants delivers more than thrice the welfare gains than from cost-equivalent, place-based adaptation measures. These results have implications for the allocation of scarce climate adaptation funds in developing countries.
