Investigating the effects of sea-level rise on morphodynamics in the western Giens tombolo, France

Rising sea level along with the occurrence of greater and more frequent storms would cause not only coastal flooding, but also beach erosion and shoreline retreat problems. The Almanarre beach along the western Giens tombolo is socio-economically and heavily vulnerable to accelerated sea level rise due to its high touristic value and low-lying topography. Therefore, it is necessary to quantify the impacts of sea level rise (SLR) on the morphodynamics in this area, e.g. to evaluate the relationship between the beach erosion and SLR. Coupled hydrodynamic and sediment transport numerical models are used to investigate the changes in current, wave and sediment dynamics when sea level rises. A total of 16 scenarios with and without SLR are simulated. The effectiveness of the coupled model is assessed by comparison of simulated values with available field measurements. The results presented in this work should be useful in the investigation of other coastal regions.