Some features of the dynamic structure of a deep estuary

A boundary-layer formulation for the dynamic structure of a deep estuary is developed. Cross-stream averages are used, but the boundary-layer structure is shown to depend on the cross-stream geostro- phic constraint. A similarity transformation and a weighted residual method are used to derive an approximate solution for the velocity and salinity structure of the upper layer. This solution indicates that, in the central regime of the estuary, outflow extends through the entire halocline. Inflow takes place in a much less stratified lower layer, and mass exchange between the layers is by upwelling. This structure is modified in the outer regime of the estuary where mixing between the layers develops and in the inner regime where a sharp halocline develops and where mass exchange is by entrainment. The implications of the dynamics for the flushing process and for pollutant movement and dispersion are discussed. 1974 NOS (National Ocean Service) Library Public Domain 1935