HR: 1340h
AN: OS13A-0506    [Abstracts]
TI: Estuary River Plume Connections
AU: * MacCready, P
EM: parker@ocean.washington.edu
AF: University of Washington, Box 355351, Seattle, WA 98195-5351 United States
AB: Estuarine circulation and mixing determine the boundary values for coastal river plumes, controlling the initial volume flux and density contrast, as well as the initial chemical and biological properties. At the same time, the presence of the river plume changes the oceanic boundary condition for the estuary. Analytical theory and 3D numerical simulation with the ROMS model are used to explore the linkage between these two dynamical systems. Three questions are addressed. First, can strong tidal currents at the mouth of the estuary overcome the constraint of hydraulic control on the exchange flow there (Stommel's "overmixed" solution), and thereby decreasing the minimum density contrast of the river plume? Second, does the presence of the river plume substantially change the oceanic boundary condition for the estuary, leading to a smaller than expected value for the non-gravitational dispersion coefficient near the mouth? Third, where on the shelf does the water flowing into the estuary come from? Is it drawn from along the coast as proposed by Beardsley and Hart (1978, JGR), or do tidal currents bring it in symmetrically from all directions offshore?
UR: http://www.ocean.washington.edu/rise/index.htm
DE: 4219 Continental shelf processes
DE: 4235 Estuarine processes
DE: 4255 Numerical modeling
DE: 4560 Surface waves and tides (1255)
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting