Networked shorelines: A review of vulnerability interactions between human adaptation to sea level rise and wetland migration

Facing urgent climate risks, many human and non-human actors are adapting to climate change with adaptations that sometimes shift vulnerabilities to other actors. Shifting vulnerabilities is a type of maladaptation and understanding them is a critical component of adaptation planning given the growing incidence of maladaptation across many sectors and regions. This review creates an analytical framework, called the Vulnerability Interactions Framework, to identify instances of shifting vulnerabilities from across the natural and social science literature and interpret them using a systematic approach. To demonstrate its utility, the analytical framework is applied in the context of coastal adaptation to sea level rise on the topics of coastal squeeze and wetland migration. Along certain shorelines, humans are building protective infrastructure, such as sea walls and levees, to protect themselves from sea level rise. Meanwhile, coastal wetlands—one of the world’s most valuable ecosystems—are able to adapt to sea level rise when they can migrate landward. This wetland adaptation is often blocked by human shoreline development and infrastructure—a phenomenon known as coastal squeeze. Yet migrating wetlands may also impact human actors in negative ways. This review identifies 53 distinct ways that vulnerabilities can shift across human and non-human actors on physical, economic, environmental, social, cultural, and institutional dimensions. These interactions reflect particular biophysical and social contexts and can operate on multiple spatial and temporal scales. Because of these complex interactions, adaptation planning must look towards developing solutions that are cross-sectoral and cross-scalar in scope, place adaptation within a larger socio-ecological context, consider a phased approach, engage with communities, build local adaptive capacity, and address personal, social, and cultural losses inherent in coastal transformations. Overall, the Vulnerability Interactions Framework can be used as a research or planning tool to map observed or hypothetical shifts in vulnerability.