HR: 13:55h
AN: OS33D-02    [Abstracts]
TI: Northwest Australian Shelf Dynamics Experiment: Shelf-Edge Processes
AU: * Bahr, F
EM: fbahr@whoi.edu
AF: Woods Hole Oceanographic Institution, Mail Stop 30 Woods Hole Oceanographic Institution, Woods Hole, MA 02543 United States
AU: Shearman, R
EM: shearman@coas.oregonstate.edu
AF: College of Oceanic and Atmospheric Sciences, College of Oceanic and Atmospheric Sciences Oregon State University, Corvallis, OR 97331 United States
AU: Brink, K H
EM: kbrink@whoi.edu
AF: Woods Hole Oceanographic Institution, Mail Stop 30 Woods Hole Oceanographic Institution, Woods Hole, MA 02543 United States
AB: Repeated, well-resolved cross-shelf sections of temperature, salinity and currents were made near the northwestern Australian shelf edge during June and July, 2003, using a towed undulating instrument platform (SeaSoar) and a ship-based acoustic Doppler current profiler (ADCP). The shelf waters are typified by strong semidiurnal tides and by intense evaporative densification. When the shelf-edge alongshore flow was poleward, saltier waters were found only over the shelf, but did not extend offshore of the shelfbreak. Most of the sampling occurred while there was a bottom-trapped equatorward flow along the shelf edge, and there was invariably a tongue of salty water protruding offshore of the shelf edge into the ambient fresher water offshore. This tongue was typically centered at about 125m depth, and was about 50m thick. The salty tongue's origin appears to be related to bottom Ekman transport convergence (due to cross-shelf variations in alongshore flow). Although the salty tongue was always present when there was an equatorward shelf-edge flow, it was subject to considerable temporal variability that may be associated with linear or nonlinear internal tides generated at the shelf break. It thus appears that shelf-slope exchanges may be strongly influenced by the sense of alongshore flow.
DE: 4219 Continental shelf processes
DE: 4516 Eastern boundary currents
DE: 4528 Fronts and jets
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting