HR: 16:45h
AN: OS14B-04    [Abstracts]
TI: Vertical Phase Variation in Mean and Oscillatory Surf Zone Currents
AU: * Lippmann, T C
EM: lippmann.2@osu.edu
AF: Ohio State University, Byrd Polar Research Center 1090 Carmack Rd., Columbus, OH 43210 United States
AU: Thornton, E
EM: thornton@nps.edu
AF: Naval Postgraduate School, Department of Oceanography 833 Dyer Road, Monterey, CA 93943 United States
AU: Stanton, T
EM: stanton@nps.edu
AF: Naval Postgraduate School, Department of Oceanography 833 Dyer Road, Monterey, CA 93943 United States
AB: Considerable effort has been expended in measuring and modeling the vertical variation of mean flow patterns in and near the surf zone. In general, mean cross-shore currents are characterized by an undertow profile, whereas alongshore currents have an approximately logrithmic boundary layer spanning the water column. Additionally, temporal variations in flow patterns occur on time scales associated with changes in wave forcing, instabilities of the mean flow, and through non-local circulation induced by bathymetric irregularities. In the presense of strong, sometimes pulsating, horizontal circulation, such as that associated with rip currents, the typical undertow profile can modulate between an undertow and logrithmic form. In this work, we examine the temporal variation and phase structure in vertical profiles of the mean flow patterns on time scales ranging from a few minutes to several hours. Observations used in this work were obtained during the Duck94 field experiment held in Duck, NC, from a vertical stack of 2-axis electromagnetic flow sensors deployed on a movable sled, and surface flow estimates obtained from PIV analysis of video data. This research was supported by the Office of Naval Research.
DE: 4275 Remote sensing and electromagnetic processes (0689)
DE: 4294 Instruments and techniques
DE: 4546 Nearshore processes
DE: 3020 Littoral processes
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting