Swash Hydrodynamic from Non-hydrostatic Modeling and Multi Sensor Observations

Abstract Several in situ measurements from a variety of instruments acquired in 2015 at Nha Trang Vietnam are used to test the ability of a non-hydrostatic model CROCO to reproduce wave physics at near and inner shore environments with a special focus on Run-up excursion. In particular, a LiDAR is used to determine hydrodynamics and morphological changes at the swash zone, ADCP is used as the offshore reference and cameras provide additional quantitative information about Run-up excursion. Results show a tidally controlled environment with strong modulation of the significant wave height that is well reproduced by CROCO. Inner-shore hydrodynamics are also well reproduced by CROCO and Run-up indicators show a strong correlation and low dispersion with respect to observations (R2 > 0.9; SI < 10%). Despite the use of a fixed bathymetry during the simulations, the support of LiDAR in getting foreshore slope helps to improve the overall performance of the model. The coupling of CROCO to a sediment model is still to be tested to obtain more insights about bathymetry influence in this kind of environment. Numerical models to predict coastal flooding and overtopping, nourished by non-expensive remote sensing information, appears now to be a possibility.