Research reviewed in AR4 and AR5 observed that at higher rates of socioeconomic development, the in situ adaptive capacity of households and institutions rises, and climatic influences on migration correspondingly decline. Recent evidence adds further support for such conclusions  . Population growth rates are currently highest in low-income countries , many of which have high rates of exposure to climatic hazards associated with population displacement, further emphasising the importance of socioeconomic development and adaptive capacity-building. Although country-specific scenarios for socioeconomic development and population are embedded in SSPs, research into future migration flows under climate change has not made great use of these. One of the few studies to do so found that safe and orderly international migration tends to increase wealth at regional and global scales in all SSP narratives, which in turn reduces income inequality between countries . International barriers to safe and orderly migration may potentially impede progress towards attainment of the objectives described in the SDGs and increase exposure to climatic hazards in low- and middle-income countries .
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report