Wave height distributions on shallow foreshores

Wave height distributions on shallow foreshores deviate from those in deep water due to the effects of the restricted depth-to-height ratio and of wave breaking. Laboratory data of wave heights on shallow foreshores of different slopes have been analysed to determine these effects and to derive generalised empirical parameterisations. A model distribution is proposed consisting of a Rayleigh distribution, or a Weibull distribution with exponent equal to 2, for the lower heights and a Weibull with a higher exponent for the higher wave heights. The parameters of this distribution have been estimated from the data and expressed in terms of local wave energy, depth and bottom slope, yielding a predictive model that is found to be significantly more accurate than existing expressions.