ABSTRACT
A spectral evolution model is implemented of the extended Boussinesq equation which can be used for varying bathymetry even in deep water region. In this model, a contribution of the triad nonlinear interaction can be segregated from that of the bottom shoaling effect. For a simple one-dimensional case, an attempt to express the triad interaction as a source function term in the energy balance equation is shown. Numerical sensitivities for different initial phases and different frequency band widths are investigated. Itis observed that the numerical results are dependent on the initial phases. An ensemble mean of many realizations or a frequency-averaged estimation of a single realization with a very fine frequency resolution provides convergent results. These numerical estimations of the spectral model agree well with experimental data for finite-amplitude waves propagating over a bar in shallow water.
