Recent Dynamics of the Mouth Bar in Ebro River (NW Mediterranean Sea)

Abstract Deltas are highly dynamic and play a crucial role in socio-economic activities and environment, yet they are very vulnerable to climate changes and human pressures. This contribution focuses on the recent dynamics of the mouth bar in the Ebro River (NW Mediterranean Sea) due to changes in hydrodynamics conditions. The low river discharge period occurred from July 2022 to November 2023 and the increase of south and southwest waves have significantly influenced the hydro-morphodynamics of the river mouth and mouth bar. These conditions caused littoral transport to dominate the morphology of the beach, generating a salient on the left side of the mouth and causing the mouth bar to emerge and deflect towards the left. Using Sentinel 2 images processed with Google Earth Engine, orthophotos, wave and river discharge data along with data from lagrangian buoys launched in field campaigns indicates a directional shift of the main river channel discharge from northward to eastward, driven by morphological changes on the coast and seabed due to alterations on the alongshore sediment transport.