Will climate change increase or decrease migration in rural Africa?

In a recent working paper Cristina Cattaneo and I examine how climate affects migration decisions at the household level in rural Ghana and Nigeria. Contrary to most of the other papers in the literature, we deal with climate - i.e. the long-run average of weather - rather than with climate shocks.

Is migration an adaptation that households in Ghana and Nigeria use to cope with current climate?

If the answer is yes, it is reasonable to expect that migration will also be an adaptation to future climate change.

The data to test these predictions are drawn from two different household surveys: the Nigeria General Household Survey and the Ghana Living Standard Survey. We find a hill-shaped relationship between temperature in the dry season and the propensity to migrate in households that operate farms. We also find a significant hill-shaped relationship between precipitations in the wet seasons and the propensity to migrate in farm households. Climate has instead no significant impact on the propensity to migrate in non-farm households. Climate change scenarios generated by General Circulation model reveal that, ceteris paribus, migration may decline in Ghana and in Nigeria.

I copy below maps of marginal effects of temperature and of precipitations on the probability of a household to have at least one migrant member.

Cattaneo, C. and E. Massetti. 2015. “Climate and Migration in Rural Ghana and Nigeria.” FEEM and Georgia Institute of Technology, mimeo.