HR: 14:00h
AN: OS33C-01 INVITED     [Abstracts]
TI: Estuary/ocean exchange as influenced by friction and width of cross-section
AU: * Valle-Levinson, A
EM: arnoldo@ufl.edu
AF: University of Florida, 365 Weil Hall, Gainesville, FL 32611, United States
AB: The lateral structure of estuary/ocean exchange flows is investigated theoretically as a function of friction and estuary's width. The relative contribution of friction is expressed through the Ekman number. In turn, the effects of estuary's width are explored with the Kelvin number. It is found that exchange flows are horizontally sheared under high frictional conditions independently of the width of the channel. The horizontally sheared pattern describes inflow in the channel and outflow over shoals. The exchange flow pattern is also horizontally sheared under weak friction and in wide channels. In that case, however, the outflow is concentrated on the left (looking into the estuary in the northern hemisphere) portion of the cross-section and inflow appears on the right. Also under weak friction, the exchange pattern becomes vertically sheared, with outflow at surface and inflow underneath, as the width of the channel becomes small. Under moderate friction the exchange pattern is both horizontally and vertically sheared for all widths. A horizontally sheared pattern is best defined in wide estuaries whereas a vertically sheared pattern dominates in narrow channels. Observations in tropical and subtropical systems are placed in the context of these findings.
DE: 4203 Analytical modeling and laboratory experiments
DE: 4235 Estuarine processes (0442)
DE: 4508 Coriolis effects
DE: 4562 Topographic/bathymetric interactions
SC: Ocean Sciences [OS]
MN: 2007 Joint Assembly