HR: 10:35h
AN: OS32B-02    [Abstracts]
TI: From the CMV Oleander Project: A Study of the Shelfbreak Front of the Middle Atlantic Bight From Long-term ADCP and Hydrographic Data
AU: * Flagg, C N
EM: cflagg@ms.cc.sunysb.edu
AF: Marine Sciences Research Center State University of New York, Endeavour Hall, Rm 203, Stony Brook, NY 11794-5000 United States
AU: Dunn, M
EM: maureen.dunn@sunysb.edu
AF: Marine Sciences Research Center State University of New York, Endeavour Hall, Rm 203, Stony Brook, NY 11794-5000 United States
AU: Wang, D
EM: dpwang@notes.cc.sunysb.edu
AF: Marine Sciences Research Center State University of New York, Endeavour Hall, Rm 203, Stony Brook, NY 11794-5000 United States
AB: Utilizing the first decade of shipboard ADCP data as well as XBT and surface salinity data obtained from the CMV Oleander, this study is focused on the mean structure, and seasonal and interannual variability of the frontal zone at the edge of the shelf of the Middle Atlantic Bight. The early analysis showed that more than half the data in the frontal zone were influenced by warm core rings and that removing the confounding influence of the rings was vital if the true structure of the front was to emerge. From the culled data set of 128 transects of the front with sufficient coverage we have proceeded to generate a velocity description following the core of the frontal jet showing a maximum, surface intensified velocity of more than 0.25 ms-1, a vertical extent of roughly 80 m, a half-amplitude width of about 20 km and an alongshore transport of ~0.34 Sv. The maximum mean relative vorticity of the jet is 0.56*f. The alongshore jet is accompanied by a substantial surface intensified convergent flow that implies a maximum down-welling in the center of the jet of ~30 m/day. The seasonally the shelfbreak jet has its minimal velocities during the summer months, increasing to maximal velocities during the winter before decreasing agin in the spring. An interesting feature that emerges from the ADCP data is that while the shelfbreak frontal jet is usually assumed to consist of a single high-speed core, in fact, the jet often exhibits multiple high velocity extrema, the existence of which appears to undergo a seasonal progression.
DE: 4219 Continental shelf processes
DE: 4223 Descriptive and regional oceanography
DE: 4512 Currents
DE: 4528 Fronts and jets
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting