Swash on steep and shallow beaches.

Abstract

Relates theoretical and laboratory studies on swash oscillations to field observations of swash. Outlines the saturated swash hypothesis for monochromatic incident waves (wind wave frequency band) and discusses whether the field data agree with the equations given. Plots the ratio of observed significant swash height (incident wave band) significant incident wave height versus the surf similarity parameter. Discusses differences between the field data sets on surf beat frequencies. Studies an apparent linear dependence between incident wave and surf beat energy levels. Discusses the dissipative influence of a beach and effect of cut off frequency alteration on data set characteristics. Decomposes the long wave into incoming and outgoing and separately correlates these with the wind wave envelope. The shoreward propagating surf beat appears to be coupled to incident wave groups. (C.J.U.)