Outward migration may alter population dynamics and income inequality


Climate change impacts may drive affected populations to migrate. However, migration decisions in response to climate change could have broader effects on population dynamics in affected regions. Here, I model the effect of climate change on fertility rates, income inequality, and human capital accumulation in developing countries, focusing on the instrumental role of migration as a key adaptation mechanism. In particular, I investigate how climate-induced migration in developing countries will affect those who do not migrate. I find that holding all else constant, climate change raises the return on acquiring skills, because skilled individuals have greater migration opportunities than unskilled individuals. In response to this change in incentives, parents may choose to invest more in education and have fewer children. This may ultimately reduce local income inequality, partially offsetting some of the damages of climate change for low-income individuals who do not migrate.

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Figure 1: Impact of migration on labour market in the sending country under three RCP scenarios for two cases of climate-dependent and climate-independent migration.
Figure 2: Impact of migration on income inequality under three RCP scenarios for two cases of climate-dependent and climate-independent migration.
Figure 3: Impact of migration on fertility rate under three RCP scenarios for two cases of climate-dependent and climate-independent migration.
Figure 4: Impact of migration on output per capita under three RCP scenarios for two cases of climate-dependent and climate-independent migration.


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I would like to thank G. P. Casey from Brown University for assistance with developing the analytical model and for comments that greatly improved the manuscript. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no. 703399 for the project ‘Robust Policy’.

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Correspondence to Soheil Shayegh.

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Shayegh, S. Outward migration may alter population dynamics and income inequality. Nature Clim Change 7, 828–832 (2017). https://doi.org/10.1038/nclimate3420

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