Detection and attribution: Does climate change drive migration? Ascertaining the role of climate change in migration is difficult and contested , with observation-based studies either linking extreme event incidence, weather anomalies and environmental change with migration numbers or drivers , and projection studies looking at particular risks such as SLR or drought by linking increasing warming  and population growth. Despite methodological disagreement on detection and attribution of migration due to climate change, there is medium confidence that higher warming and associated changes in frequency and intensity of slow-onset events  and rapid-onset events  will increase involuntary displacement in the future, especially under SSP3 and SSP4 pathways . But its role is smaller than non-climatic socio-economic drivers of migration .
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report