Abstract
Deformation of long-period giant waves, which caused serious coastal damages in Toyama and Sado Island on February 24, 2008, was investigated on the basis of field data analyses and numerical modelling. Field data obtained at the depth of 12.8m indicated significant nonlinear development of wave energy spectrum, both in the low frequency and in the double frequency ranges. Strong longshore currents were rapidly developed at the same time with the attack of giant waves. Wave energy concentration to the damaged area was found to be resulted by interactions among waves, bathymetry and nearshore currents.
