Accession Number : ADA609495


Title :   A Parametric Model for Barred Equilibrium Beach Profiles


Descriptive Note : Journal article


Corporate Author : NAVAL RESEARCH LAB STENNIS DETACHMENT STENNIS SPACE CENTER MS OCEANOGRAPHY DIV


Personal Author(s) : Holman, Robert A ; Lalejini, David M ; Edwards, Kacey ; Veeramony, Jay


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a609495.pdf


Report Date : 10 May 2014


Pagination or Media Count : 12


Abstract : Environment predictions for locations for which bathymetric data is missing, poor or outdated requires the use of some sort of representative bathymetric form, usually one that is concave up but monotonic. We propose and test a parametric form that superimposes realistic sand bars (Ruessink et al., 2003b) on a background profile that mixes a concave up nearshore with a planar far field behavior. Implementation at any new site involves estimation of five parameters, three that can be found from approximate information from climatology or old offshore charts, one that can be estimated by almost any remote sensing modality and one, hsea that is less well understood but mostly affects deeper bathymetry that has little impact on the resulting surf zone hydrodynamics. Tests against several hundred surveys at three diverse locations show that bathymetry is better estimated by the new barred form than with a previous monotonic profiles in about 80% of cases. The remaining cases are usually associated with the parametric prediction of bars that look realistic but are out of phase. The presence of parametric bars has an even greater impact on predicted hydrodynamics since wave breaking is concentrated at sand bar locations. Modeled cross-shore transects of alongshore current and wave height over the measured survey profile are well represented by modeled transects over the barred parametric form but not for results over a Dean profile. The peak alongshore current strength and location are particularly sensitive to the presence of a sand bar.


Descriptors :   *BATHYMETRY , *EQUATIONS , *ESTIMATES , *HYDRODYNAMICS , *PARAMETRIC ANALYSIS , BEACHES , CLIMATOLOGY , DEPTH , FIELD TESTS , MODELS , OBSERVATION , PREDICTIONS , REMOTE DETECTION , STATISTICS


Subject Categories : Physical and Dynamic Oceanography
      Numerical Mathematics
      Theoretical Mathematics
      Statistics and Probability
      Fluid Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE