HR: 0800h
AN: OS21B-1237    [Abstracts]
TI: The Effects of Tropical Cyclones on Sediment Transport Patterns Adjacent to a Hardbottom Reef in Onslow Bay, North Carolina
AU: * Wren, A
EM: wrenp@tamug.edu
AF: University of North Carolina at Wilmington - Center for Marine Science, 5600 Marvin Moss Lane, Wilmington, NC 28409 United States
AU: Leonard, L A
EM: lynnl@uncw.edu
AF: University of North Carolina at Wilmington - Center for Marine Science, 5600 Marvin Moss Lane, Wilmington, NC 28409 United States
AB: An instrumented frame has been maintained on the mid-continental shelf in Onslow Bay, North Carolina, approximately 43.5 km off the coast of Wilmington, as part of the Coastal Ocean Research and Monitoring Program (CORMP) at the University of North Carolina at Wilmington. The attached instrumentation includes a downward looking Pulse-Coherent Acoustic Doppler Profiler (PC-ADP), which measures boundary layer conditions in the lower 1.5 m above the seabed, and an upward-looking Acoustic Doppler Current Profiler (ADCP) which measures velocity profiles in the upper water column. The frame was present on the shelf during the passage of four tropical cyclones that occurred between September 2003 and September 2004. All four tropical systems varied in their angle of approach, duration, and intensity as they passed by the study site. Simultaneous measurements of flow velocities from the surface to the seabed, along with acoustic backscatter measurements and seabed elevation data, have been obtained during these tropical storm events. Wave orbital velocities and mean current speeds at 1 m above the bed were used to calculate bed shear stresses during the events using the Styles and Glenn bottom boundary layer model (2000). The magnitude of suspended sediment transport during each tropical cyclone event has been quantified and characterized. In addition, the effects that a nearby hardbottom reef may have on the sediment transport patterns in the vicinity of the study site have also been examined.
DE: 3022 Marine sediments--processes and transport
DE: 3307 Boundary layer processes
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting