HR: 1340h
AN: NG33A-0886    [Abstracts]
TI: Longshore sediment transport from Maine to Florida: Comparison of literature compilation to model results based on WIS hindcast deep-water data
AU: * Tebbens, S F
EM: sarah.tebbens@wright.edu
AF: Wright State University, Dept. of Physics, 3640 Colonel Glenn Hwy, Dayton, OH 45435 United States
AU: * Tebbens, S F
EM: sarah.tebbens@wright.edu
AF: University of South Florida, College of Marine Science, 140 Seventh Ave., South, St. Petersburg, FL 33701 United States
AU: vanGaalen, J
EM: vangaale@seas.marine.usf.edu
AF: University of South Florida, College of Marine Science, 140 Seventh Ave., South, St. Petersburg, FL 33701 United States
AB: We examine the regional longshore sediment transport pattern of the seaward coast of the United States and Gulf of Mexico from northern Maine to Tampa Bay, Florida. A regional interpretation of longshore transport compiled from published field and modeling studies is compared to gross and net potential sediment transport directions and rates determined with a model using wave information study (WIS) hindcast data. The approach will assess the validity of using WIS hindcast data to determine longshore transport rates and directions. Using an approach herein called the WIS deep-water method, the WIS deep-water wave characteristics are used in the equations of Ashton et al (2003) to model the direction and rate of longshore sediment transport at roughly 25 km intervals along the coast. The derived transport directions, including the indicated location of nodal zones, generally agree with published field studies, although there are some local inconsistencies, particularly near inlets, shoals and irregular bathymetry. Trends in longshore transport rates, such as increases and decreases in gross transport rates, are well represented by the potential transport rates derived by the WIS deep-water method. The discrepancies between the published field studies and WIS results are apparently primarily due to assumptions in the WIS model, such as assuming shore-parallel bathymetric contours. We conclude that where carefully conducted long-term field studies are available they are the preferred means of determining accurate longshore sediment transport rates and directions. When other data are not available, the WIS deep-water method is found to provide an accurate regional determination of sediment transport directions and relative magnitudes for roughly 70 percent of the study area at a fraction of the effort and cost.
DE: 9325 Atlantic Ocean
DE: 4546 Nearshore processes
DE: 3210 Modeling
SC: Nonlinear Geophysics [NG]
MN: 2004 AGU Fall Meeting