Data Interpretation

Internal climate mobility refers to the movement of people within national borders that is motivated by the adverse effects of sudden- or slow-onset climate impacts. Climate mobility occurs over different distances and can be temporary, recurrent, or permanent.

This dataset compiles the results of the Africa Climate Mobility Model applied to four different scenarios and three different time periods (2030, 2040, 2050). Results are shown as the total number of migrants driven by climate impacts per grid cell, as well as the percentage difference between the number of migrants driven by climate impacts (climate mobility) per grid cell compared to the number of migrants driven by other factors  (besides climate risks).

Data Modelling

The Africa Climate Mobility Model is based on a gravity model of Africa’s future spatial population. The model estimates the number of people arriving or leaving rural and urban areas, and their future locations. It compares the population distributions that incorporate likely and optimistic projected climate impacts as well as future socio-economic scenarios based on future development trajectories for Africa.

The model uses two climate scenarios (RCP2.6 and RCP6.0) to inform the model’s climate impacts on water, agricultural, and ecosystem sector change, as well as flood risk provided by the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP), which are incorporated in projections of future population distributions. The model accounts for population change projections and considers multiple climate stressors as inputs, including climate impacts on water (floods), food security (water availability and crop production), coasts (sea level rise), safety (armed conflicts, refugee camps), and economies (poverty).

Projected levels of population growth for each country and future tendencies towards dispersion or concentration of the population are based on two development scenarios embodied in the Shared Socioeconomic Pathways (SSPs). The development scenarios indicate the difference in climate mobility based on future progress towards more inclusive development in Africa on education, population growth, technology, regional integration and cooperation, economic growth and poverty reduction, and level of urbanisation.

The model is calibrated by assessing the sensitivity of past shifts in population distribution to the sectoral climate impacts (as well as non-climate related drivers), and then using those coefficients in combination with projected deviations in sectoral impacts on a grid-cell basis to alter the place attractiveness (population potential) of each grid cell in five year increments out to 2050. Essentially, positive differences represent climate mobility into an area, and negative differences represent climate mobility out of an area.

For more information on the Africa Climate Mobility Model read Appendix 2 in the GCCM Report: Africa Shifts.

Source

ACMI Africa Climate Mobility Model, 2022