A model for the generation of two-dimensional surf beat

Journal of Geophysical Research C: Oceans



A finite difference model predicting group-forced long waves in the nearshore is constructed with two interacting parts: an incident wave model providing time-varying radiation stress gradients across the nearshore, and a long-wave model which solves the equations of motion for the forcing imposed by the incident waves. Both shallow water group-bound long waves and long waves generated by a time-varying breakpoint are simulated. Model-generated time series are used to calculate the cross correlation between wave groups and long waves through the surf zone. The cross-correlation signal first observed by Tucker (1950) is well predicted. For the first time, this signal is decomposed into the contributions from the two mechanisms of leaky mode forcing. Results show that the cross-correlation signal can be explained by bound long waves which are amplified, though strongly modified, through the surf zone before reflection from the shoreline. The breakpoint-forced long waves are added to the bound long waves at a phase of pi/2 and are a secondary contribution owing to their relatively small size.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title A model for the generation of two-dimensional surf beat
Series title Journal of Geophysical Research C: Oceans
DOI 10.1029/91JC03147
Volume 97
Year Published 1992
Language English
Publisher American Geophysical Union
Publisher location Richmond, VA
Contributing office(s) Woods Hole Coastal and Marine Science Center
Description 13 p.
First page 5623
Last page 5635
Online Only (Y/N) N
Additional Online Files (Y/N) N