HR: 0800h
AN: OS41A-0167    [Abstracts]
TI: High Resolution Bathymetric LIDAR Measurements at San Luis Obispo Bay, CA
AU: * Bensky, T
EM: tbensky@calpolyl.edu
AF: California Polytechnic State University, Physics Department, San Luis Obispo, CA 93407, United States
AU: Seck, C
EM: cseck@calpoly.edu
AF: California Polytechnic State University, Physics Department, San Luis Obispo, CA 93407, United States
AU: Smith, D
EM: drsmith@calpoly.edu
AF: California Polytechnic State University, Physics Department, San Luis Obispo, CA 93407, United States
AB: The movement of sand by ocean currents is an invisible but critically important phenomenon to coastal communities and sea-vessel-dependent economies such as in San Luis Obispo Bay. Over time, sand (or sediment) can cause beaches to erode or rebuild and harbors to "silt up." Dredging harbors is an obvious control mechanism, but the process is messy and expensive. Thus, such "coastal management" decisions should be well informed. Unfortunately, the effect of ocean currents on sand and sediment levels on the ocean floor is poorly understood in part because it is hard to observe: it occurs at the bottom of the ocean. But questions remain: What are the sand movement dynamics at the bottom of San Luis Obispo Bay? Is the bay filling in? Emptying out? What effects do persistent wind and wave patterns have on the ocean bottom? What about large storms? In order to answer these questions, we have installed a bathymetric Light Detection And Ranging (LIDAR) system on the Cal Poly Center for Costal Marine Sciences Pier in Port San Luis Obispo, California. Using a 1 Watt Nd:YAG laser operating at 532nm and a single photon detector, we have observed photons scattered off the ocean floor (benthic boundary layer or BBL). The photon detector is attached to a high resolution, multiple-stop timer, with 15 picoseconds of event-to-event resolution. This yields an approximate 1 cm resolution of LIDAR ranging and hence sediment transport dynamics. In this poster, we will present preliminary results of our work including evidence of surface- and BBL-scattered photons.
UR: http://atom.physics.calpoly.edu/faculty/index.php/LIDAR
DE: 4211 Benthic boundary layers
DE: 4217 Coastal processes
DE: 4558 Sediment transport (1862)
DE: 4594 Instruments and techniques
DE: 4863 Sedimentation (1861)
SC: Ocean Sciences [OS]
MN: 2007 Fall Meeting