Differential effects of extreme climate impacts on global district-level net migration

Climate change significantly impacts human mobility, yet understanding the temporal dynamics and cumulative effects of multiple climate events remains understudied. This research investigates the impact of climate extremes--droughts, floods, crop failures, and tropical cyclones--on district-level net migration from 2000 to 2019. Using global climate impact simulations from the Inter-Sectoral Impact Model Intercomparison Project and recent sub-national migration data, we observed initial increases in positive net migration following floods, but this trend declines after one year in regions typically experiencing net migration losses. Droughts show delayed migration responses in similar areas, possibly due to liquidity constraints. Tropical cyclones initially increase net migration, particularly in destination areas, but this is followed by a decline after two years and stabilization thereafter. Importantly, consecutive climate events lead to a combined reduction in positive migration, reflecting the total impacts. These findings highlight the need for migration policies that address both immediate and long-term responses to climate extremes.