Multiscale analysis of coastal social vulnerability to extreme events in Brazil

Issues related to prevention and mitigation of extreme events' impacts, intensified by climate changes, have been receiving progressive attention from the academic community. Impacts are increasingly expensive for the society, particularly in coastal zones, where population growth and concentration of economic activities modify the landscape and alter the natural balance of coastal processes, contributing to increase population's vulnerability to these events. Considering the growing need to measure the social vulnerability of coastal populations and the lack of studies that focus on the effects of changing spatial scales over vulnerability analysis, this article proposes a methodology for obtaining a multiscale Coastal Social Vulnerability Index to extreme events (SVI-Coast) for 281 municipalities facing the sea in Brazil. The proposed methodology employed data from the most recent available national demographic census (2010), over which descriptive and multivariate statistical techniques were applied, considering three units of spatial aggregation: states, municipalities, and census sectors. Results show that in Brazil there is a tendency for concentration of greater social vulnerabilities in North and Northeast regions and that the key variables responsible for this are income and access to infrastructure, which are underprovided in these regions. This methodology can be replicated on multiple spatial scales, contributing to provide scientific knowledge capable of assisting decision-making by local and regional managers, especially by identifying priority areas, which need urgent actions for mitigation and reduction of coastal social vulnerability.