Feature extraction of coastal waves based on phase-resolved simulation and bidimensional empirical mode decomposition

Waves in the coastal region have a profound effect on the physical and ecological environment. When waves enter the coastal region from the open sea, their dynamics are determined by several complex physical processes such as shoaling, refraction, breaking, etc. As a result, the wave field becomes spatially inhomogeneous, which poses challenges to traditional Fourier analysis. To address this issue, we conduct wave-phase-resolved simulations using a high-order spectral method, where the nonlinear wave-bottom interaction, the nonlinear three-wave and four-wave interactions are captured. The initial wave conditions are constructed for sea states with different wave field properties. The bathymetry profile varies continuously from deep water to shallow water. The obtained wave data is then analyzed using an adaptive bidimensional empirical mode decomposition algorithm, where the wave dynamics in the deep water and shallow water regions are captured on separate components.