Three-Dimensional Salinity Simulations of South San Francisco Bay

A conservative transport method and a two-equation turbulence closure model are added to an established three-dimensional hydrodynamic model. The resulting model is applied to simulate the development of the salinity field in South San Francisco Bay. All model parameters in the salinity simulation are identical to those used in a model calibration in which the model is shown to reproduce current meter data accurately. The 64-day time period studied is characterized by low freshwater input. During this period, the observed salinity data is reproduced well by the model. Because no model parameters are adjusted, the salinity simulation is considered to be a verification of the model. Once the model is verified, it is used to explore the importance of stratification and baroclinic pressure gradients on long-term transport. It is concluded that, under conditions of moderate density gradients, the density-driven flow and mild periodic stratification that results have a significant effect on scalar transport.