Modeling the Variations of Freshwater Inflows and Tidal Mixing on Estuarine Circulation and Salt Flux

Abstract

ABSTRACT Chua, V.P., 2013. Modeling the variations of freshwater inflows and tidal mixing on estuarine circulation and salt flux. An idealized estuary model is employed to simulate the effects of freshwater inflows and tidal mixing on estuarine circulation and salt flux. The model is forced with idealized tides at the coastal ocean boundary, and constant freshwater inflows are imposed at the river end to allow steady state conditions to be achieved. The dependence of length scale L and diffusive fraction ν is stronger with tidal mixing compared to inflows, and this indicates that estuarine circulation and salt flux have a stronger dependence with tidal mixing than inflows. L is proportional to inflows to the −1/3 power and is proportional to tidal mixing to the −2/3 power, while ν is proportional to inflows to the −0.5 power and is directly proportional to tidal mixing. The importance of tidal mixing in estuarine circulation as a result of the coupling between vertical mixing and stratification is reinfor...