Erosion and Accretion of Beach and Spit Systems in Northwest Spain: A Response to Human Activity

Abstract

Abstract Three beach and spit systems have been studied in northern Galicia, along the northwest coast of Spain, within the regional context of sea level rise and coastal erosion. Each system forms part of an estuary's mouth complex within the inner part of the Ortigueira, Barqueiro, and Viveiro rias. Erosive processes along the coast have been characterised and been found to affect cliffs, beaches, and archaeological sites. To compare both long-term (decadal) and short-term (annual) erosion and accretion trends among estuaries, we analysed the morphodynamic characteristics, the degree of human occupancy, and the historical evolution of each system and monitored two profiles at each beach. Dynamic parameters—dimensionless fall velocity and relative tidal range—were calculated for the characterisation of beaches, and maritime climate data—significant wave height (Hs), peak period (Tp), wave fetch direction, and wave period were obtained, and wave height reduction was estimated for all estuaries. Detailed a...