There is a growing consensus that sea-level rise will have a significant influence on future patterns of population mobility. Populations across the globe are already experiencing the impacts of sea-level rise, particularly in small island developing states (SIDS) and low-lying coastal regions. Despite an expanding body of research on the climate-migration nexus, there is a lack of consensus about the quality, magnitude, and even direction of the impacts of sea-level rise on migration.
Through a comprehensive review of the existing literature, this chapter offers a critique of existing approaches to research and conceptual models of the impact of sea-level rise on migration. In doing so, it identifies future research directions, including suggested future modeling techniques, and significance for policy. 
The review focuses on two key issues that are under-represented in studies to date: first, the significant impact of sea-level rise prior to inundation and the effect they will have on drivers of mobility; second, the lack of consideration around the relationship between these impacts and complex and dynamic pre-existing patterns of mobility. A significant proportion of research into sea-level rise and population mobility has focused on the impact of inundation. Exposed populations, however, will begin to experience environmental degradation as a result of sea-level rise well in advance of this, through increased storm surge, coastal erosion, and saltwater intrusion into agricultural soils and freshwater. Crucially, these effects are cumulative, leading to an intensification of environmental degradation. They exert heightened stress on livelihoods, particularly those related to agriculture, and ultimately threaten the safety of people. Prior studies often conceptualize mobility decision-making as a binary choice between whether to “migrate” or to “stay.” Migration, however, represents a dynamic, non-equilibrium system, where mobility decision-making evolves in response to shifting influences and drivers.
Understanding the potential influence of sea-level rise, therefore, requires an analysis of how the differing, but interrelated, impacts of sea-level rise influences the pre-existing drivers of population mobility. This literature review focuses on examining how the additional stressors resulting from sea-level rise may exacerbate and intensify migration flows. It also draws on previous empirical studies to suggest conditions under which the cumulative effects are such that pre-existing patterns of mobility break down. These “threshold” conditions raise the potential for large-scale population displacement and abandonment of settlements well in advance of the timescales suggested by projections of inundation. Identifying these conditions has important implications in developing policy interventions to support vulnerable populations in meeting the threats associated with sea-level rise.
Original languageEnglish
Title of host publicationEnvironmental Migration in the Face of Emerging Risks
Subtitle of host publicationHistorical Case Studies, New Paradigms, and Future Directions
EditorsThomas Walker, Jane McGaughey, Gabrielle Machnik-Kekesi, Victoria Kelly
PublisherPalgrave Macmillan
Number of pages20
ISBN (Electronic)978-3-031-29529-4
ISBN (Print)978-3-031-29528-7, 978-3-031-29531-7
Publication statusPublished - 9 Jun 2023

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