On International Migration across the Shared Socioeconomic Pathways

Hélène Benveniste , Princeton University
Jesus Crespo Cuaresma, Wittgenstein Centre (IIASA, VID/ÖAW, WU)
Matthew Gidden, International Institute for Applied Systems Analysis
Raya Muttarak, Wittgenstein Centre for Demography and Global Human Capital, International Institute for Applied Systems Analysis (IIASA)

With climate change, migration patterns are expected to change, and will likely depend on future global socioeconomic development. The Shared Socioeconomic Pathways (SSP) represent five narratives of future development, along with quantified projections of population, income levels, inequalities and emissions over the 21st century. The population projections reflect explicit, pathway-specific international migration assumptions. Yet, migration assumptions are implicitly part of other projections. Here, we explicitly quantify the effects of international migration on income, inequality, energy consumption and emissions, by comparing original projections to scenarios of zero migration. We model income projections without migration based on two effects: changed population size, and remittances. We base remittances on migrant stocks derived from bilateral flows, modeled with a gravity model. We find that migration makes the world richer, on average, in all SSP narratives. Yet the scenario of future development significantly influences the nature of migration and remittances corridors. The migration effect on income can be substantial, up to +25% and -2% at the continental level. Furthermore, we show that migration decreases inequality between countries, has little effect on domestic inequalities in most origin and decreases inequalities in most destination countries. The magnitude of the migration effect on inequality is strongly influenced by the SSP narrative. Finally, we show that migration slightly increases energy consumption and emissions, as changes in population distribution override the reducing effect of wealth in destination countries. This new set of projections ensures consistency with the SSP interdisciplinary framework. This makes it particularly useful for assessing global policy options.

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 Presented in Session P11. Migration in a Changing Climate