Modelling Sand Wave Variation

In this chapter we present a detailed comparison between the Golden Gate sand wave field and the results of the non-linear sand wave model. As the Golden Gate sand waves show large variation in their characteristics and in their environmental physics, this area gives us the opportunity to study sand wave variation between locations, within one well measured, large area. The nonlinear model used in this chapter is presently the only tool that gives information on the non-linear large amplitude sand wave evolution. The model is used to increase our understanding in the coupling between the environmental variation and the sand wave characteristics. Results of the model show that it is able to describe the variation in the Golden Gate sand waves well when both the local oscillating tidal current and the residual current are taken into account. Current and water depth seem to be the most important factors influencing sand wave characteristics. The simulation results give further confidence in the underlying model hypothesis and assumptions.