摘要：Nearshore morphological modelling is challenging due to complex feedback betweenhydrodynamics, sediment transport and morphology bridging scales from seconds to years.Such modelling is, however, needed to assess long-term effects of changing climates on coastalenvironments, for example. Due to computational efficiency, the sediment transport driven bycurrents and waves often requires a parameterization of wave orbital velocities. A frequently usedparameterization of skewness-only was found to overfeed the coast unrealistically on a timescale ofyears—decades. To improve this, we implemented a recently developed parameterization accountingfor skewness and asymmetry in a morphodynamic model (Delft3D). The objective was to compare theeffects of parameterizations on long-term coastal morphodynamics. We performed simulations withdefault and calibrated sediment transport settings, for idealized coastlines, and compared the resultswith measured data from analogue natural systems. The skewness-asymmetry parameterization wasfound to predict overall stable coastlines within the measured envelope with wave-related calibrationfactors within a factor of 2. In contrast, the original parameterization required stronger calibration,which further affected the alongshore transport rates, and yet predicted erosion in deeper areas andunrealistic accretion near the shoreline. The skewness-asymmetry parameterization opens up thepossibility of more realistic long-term morphological modelling of complex coastal systems.
