HR: 11:50h
AN: OS32B-07    [Abstracts]
TI: Topographic Effects in a Nonlinear Model of Coastal Upwelling
AU: * Choboter, P F
EM: pchobote@coas.oregonstate.edu
AF: Oregon State University, College of Oceanic and Atmospheric Sciences 104 Ocean Admin. Bldg., Corvallis, OR 97331-5503 United States
AU: Samelson, R
EM: rsamelson@coas.oregonstate.edu
AF: Oregon State University, College of Oceanic and Atmospheric Sciences 104 Ocean Admin. Bldg., Corvallis, OR 97331-5503 United States
AU: Allen, J
EM: jallen@coas.oregonstate.edu
AF: Oregon State University, College of Oceanic and Atmospheric Sciences 104 Ocean Admin. Bldg., Corvallis, OR 97331-5503 United States
AB: Exact time dependent solutions to a nonlinear model of coastal upwelling have recently been discovered. Included in the model is cross-shore advection of density and momentum, continuous density stratification, and a geostrophic alongshore flow. The model solutions capture the drawing up of deep interior isopycnals into the surface layer in response to surface Ekman transport divergence. An equatorward velocity at the surface is driven by the Coriolis force accompanying the rapid near-surface onshore flow, and a deep poleward undercurrent develops only if there is a poleward pressure gradient present. We present new results on steady solutions of this model with variable bottom topography. A critical condition is found for the existence of the steady solution that depends on the topographic curvature. Thus, the presence of topography resembling a continental shelf break induces important differences in the qualitative behavior of the solutions. How such a topography affects the vertical structure of interior cross-shelf velocity and the associated alongshelf flow will be addressed.
DE: 4203 Analytical modeling
DE: 4279 Upwelling and convergences
DE: 4516 Eastern boundary currents
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting