2020•11•27
This review analyses global or near-global estimates of population exposure to sea-level rise (SLR)
and related hazards, followed by critically examining subsequent estimates of population migration
due to this exposure. Our review identified 33 publications that provide global or near-global
estimates of population exposure to SLR and associated hazards. They fall into three main
categories of exposure, based on definitions in the publications: (i) the population impacted by
specified levels of SLR; (ii) the number of people living in floodplains that are subject to coastal
flood events with a specific return period; and (iii) the population living in low-elevation coastal
zones. Twenty of these 33 publications discuss connections between population migration and
SLR. In our analysis of the exposure and migration data, we consider datasets, analytical methods,
and the challenges of estimating exposure to SLR followed by potential human migration. We
underscore the complex connections among SLR, exposure to its impacts, and migration. Human
mobility to and from coastal areas is shaped by diverse socioeconomic, demographic, institutional,
and political factors; there may be ‘trapped’ populations as well as those who prefer not to move for
social, cultural, and political reasons; and migration can be delayed or forestalled through other
adaptive measures. While global estimates of exposed and potentially migrating populations
highlight the significant threats of SLR for populations living in low-lying areas at or near
coastlines, further research is needed to understand the interactions among localised SLR and
related hazards, social and political contexts, adaptation possibilities, and potential migration and
(im)mobility decision-making.
Article accessible here