Migration and Environment

The concept of environmental migrants occurs frequently in the policy debate, in particular with regard to climate change and the incidence of such migration in low-income countries. This article reviews the economic studies of environmentally induced migration. It includes recent empirical analyses that try to link environmental change to migration flows and the spatial distribution of population. A consensus seems to emerge that there is little likelihood of large increases in international migration flows due to climate variability. The evidence to date shows that regional migration will be affected, however, either on the African continent or internally, within country borders. Theoretically, environmentally induced migration can be analyzed using different frameworks: the classical Harris-Todaro model of rural-urban migration, new economic geography models, models grounded in environmental economics of pollution externalities with free factor mobility, and the new economics of labor migration. I review some of the latest attempts to analyze environmentally induced migration theoretically and the policy-relevant conclusions that can be drawn.