Drivers of migration intentions in coastal Vietnam under increased flood risk from sea level rise

Elevated flood risk due to sea level rise is expected to increase migration from coastal areas. This presents an enormous policy challenge given the hundreds of millions of people living in low-lying coastal areas globally. Despite its relevance, little empirical research has been done on what drives coastal residents to migrate or stay under increased flood risk. This study aims to improve the knowledge base on this topic by collecting and analyzing unique survey data of flood-prone coastal residents in Central Vietnam. To explain permanent migration intentions under increased flood risk, we present respondents with realistic scenarios of more frequent severe flooding and utilize a theoretical framework that incorporates flood risk indicators as well as key indicators of sustainable livelihoods. Results indicate that flood risk could play a major role in future migration behavior; permanent migration intentions strongly increase under the scenarios of increased flood risk. Several individual characteristics also play an important role in the migration decision. Regression analyses reveal that respondents who implemented in situ flood adaptation, and thereby reduced their flood risk, are less inclined to migrate. Past experiences during flooding such as evacuation or the reception of help from community members or the government are also strong predictors of migration intentions. Of the sustainable livelihood indicators, social capital plays the most important role, where a larger social network inside (outside) the place of residence is negatively (positively) related to migration intentions. We draw lessons from these insights for policymakers aiming to anticipate the challenge of sea level rise-induced migration.