Dynamics of Barred Coastal Profile on a Temporal Scale of Storm Cycle
The model is developed to simulate morphodynamics of barred coastal profile on the scale of storm cycle comprising the phases of high and low wave activity. In the model CROSS-PB, main mechanisms governing sediment transport in wave shoaling and surf zones are taking into consideration, in particular, skewness and asymmetry of wave orbital velocities, undertow and infra-gravity oscillations associated with wave groups. From comparison of calculations with observed data it is concluded that the model correctly reproduces displacement of bars toward the sea during a storm and toward the shore under a moderate or weak wave conditions. The first process is shown to be provided by balance of transport mechanisms when the peak of offshore transport is located at the front slope of bar. The second process is conditioned by dominant shoreward transport and its sharp decay over the bar crest. From model testing the calibrating coefficients are estimated and it is concluded that shoreward sediment flux is mainly controlled by the wave asymmetry.