Experimental study of the reverse conversion of wave spectra

The observed deep-sea wave data are most appropriate to use in the data assimilation technique. For wave stations (e.g., the Longdong data buoy station in the northeastern Taiwan Sea near the coast), wave data must be reverse-calculate deep-sea wave data for data assimilation applications because seafloor slopes in the northeastern Taiwan Sea are acute and the distances between wave interactions during propagation are shorter. Consequently, nonlinear effects arising from the topography become insignificant as waves approach the coast from the open sea. The proposed technique to reversecalculate the deep-sea wave spectrum from the near-shore wave spectrum, based on first-order wave spectrum theory, is verified based on physical experiments. The results indicate that this method is effective and applicable to calculations of the energy at wave spectrum peaks.