Storm Surges Beach Vulnerability Index Along the Coastline of Rio de Janeiro City, From Leme to Macumba Beaches: Contributions to Coastal Management

Contributions to Coastal Management

Abstract

torm surge is a phenomenon of particular concern for the population, media, authorities, and coastal management. Sandy beaches, depositional environments located at the land-sea interface, are directly exposed to the action of storm waves. In Rio de Janeiro, this issue is exacerbated as its beaches are directly exposed to high-energy waves from the south, typical of storm surges. Using a multicriteria approach, this study presents a methodology for assessing beach vulnerability to storm surges through the development and application of an index based on two components: beach exposure and adaptive capacity. The index was applied to the urbanized oceanic beaches of Rio de Janeiro. The exposure subindex evaluates wave incidence, wave collision potential, and coastal slope. The adaptive capacity subindex includes variables such as grain size, coastal elevation and beach width. Results indicate that 27.46% of the study area has very high exposure to storm waves, 69.45% shows high adaptive capacity, and 7.95% demonstrates high vulnerability, particularly at Macumba, Leblon, and Arpoador beaches. The importance of vulnerability studies for coastal management is emphasized, contributing to the development of early warning systems and urban planning. Nature-based solutions, such as dune restoration, are recommended to enhance beach system resistance. This approach supports sustainable coastal management, reducing reliance on engineering solutions and promoting long-term resistance to storm impacts.