Heat Stress Increases Long-term Human Migration in Rural Pakistan

Nat Clim Chang. 2014 Mar 1:4:182-185. doi: 10.1038/nclimate2103.

Abstract

Human migration attributable to climate events has recently received significant attention from the academic and policy communities (1-2). Quantitative evidence on the relationship between individual, permanent migration and natural disasters is limited (3-9). A 21-year longitudinal survey conducted in rural Pakistan (1991-2012) provides a unique opportunity to understand the relationship between weather and long-term migration. We link individual-level information from this survey to satellite-derived measures of climate variability and control for potential confounders using a multivariate approach. We find that flooding-a climate shock associated with large relief efforts-has modest to insignificant impacts on migration. Heat stress, however-which has attracted relatively little relief-consistently increases the long-term migration of men, driven by a negative effect on farm and non-farm income. Addressing weather-related displacement will require policies that both enhance resilience to climate shocks and lower barriers to welfare-enhancing population movements.