Accession Number : ADA324083

Title :   Nonlinear Interaction in Ocean Surface Waves.

Descriptive Note : Final technical rept. 1 Apr 92-31 Dec 96,

Corporate Author : WASHINGTON STATE UNIV PULLMAN WA SCHOOL OF ELECTRICAL ENGINEERING AND COMPUTE R SCIENCE

Personal Author(s) : Elgar, Stephen L.

PDF Url : ADA324083

Report Date : 18 APR 1997

Pagination or Media Count : 7

Abstract : The immediate scientific objective of this project was to investigate the effects of nonlinearity in naturally occurring ocean surface gravity waves in intermediate and shallow water depths. Field observations of nonlinear effects on finite-depth waves were compared to model predictions and the changes in shapes of waves in the nearshore caused by near-resonant nonlinear wave-wave interactions were investigated. Results from this study show that waves propagating over a shallow, flat beach undergo much stronger nonlinear evolution than observed in previous experiments on moderately sloping beaches. The observed nonlinear energy transfers to higher frequencies (frequency doubling) are well described by a Boussinesq model. Reflection of low energy swell and dissipation owing to wave breaking are predicted accurately by a model based on the nonlinear shallow water equations.

Descriptors :   *OCEAN WAVES, *GRAVITY WAVES, OCEAN SURFACE, ENERGY TRANSFER, SHALLOW WATER, BATHYMETRY, NONLINEAR SYSTEMS, BEACHES, NONLINEAR ALGEBRAIC EQUATIONS.

Subject Categories : Physical and Dynamic Oceanography

Distribution Statement : APPROVED FOR PUBLIC RELEASE