Process-based one-dimensional model for cyclic longshore bar evolution

Abstract A wave-averaged process-based one-dimensional model for beach profile change was developed to predict the cyclic evolution of longshore bars. The cross-shore sediment transport was assumed to be composed of suspended load due to wave breaking and bed load due to velocity skewness, acceleration skewness, and beach slope. The model's performance was investigated using the beach profile data obtained every weekday during a 12-year period from 1989 to 2000 along a 400-m long pier at the Hazaki Oceanographical Research Station, located on the Hasaki coast of Japan, where the mean duration of bar evolution is approximately 1 year. The model was unable to reproduce bar development from a rather flat profile, possibly because some sediment movement process was missing in the model. However, the model calibrated with a 1-year data set, including the bar evolution cycle consisting of bar generation, seaward migration, decay, and new bar generation, can be used to predict the first cycles of bar evolution at Hasaki.