Longshore sand transport distribution across the surf zone due to random waves

Abstract

Analytical and numerical models are developed to predict the longshore sand transport distributions across the surf zone. The models, which also predict the root mean square wave height, H , and the longshore current, V, are compared with field data acquired from Leadbetter Beach, Santa Barbara, California, during the intensive storm period in February, 1980. The breaker coefficient, B, and the bed shear stress coefficient, c f , when equal to 1.1 and 0.005, were found to give the best ag3 reement between the cpredicted H and V with the field rms measurements. The model for a plane sloping beach predicts the maximum sand transport at offshore distance X equal to 0.8X, , where X, is the mean breakerline location, which agrees with Komar (1977a). The longshore sand transport formula, suggested by CERC (1977) , is used to calibrate the model which requires the empirical transport coefficient B to be 0.18.