Title: Slepian models for wave asymmetry and particle orbits in Gauss-Lagrange ocean waves
Authors: Georg Lindgren - Lund university (Sweden) [presenting]
Marc Prevosto - IFREMER (France)
Abstract: The basic elements in a Gauss-Lagrange model are the water particle orbits. These orbits determine the apparent wave shapes. There are very few detailed observations of the relation between particle orbit orientation and wave shape in the open ocean, and most studies are combinations of theoretical models, wave tank experiments and field data. We present Slepian models for the vertical and horizontal movements in space and time of the water particles that are located at the crests of the space waves at the time of observation. These models contain one regression term, depending on the wave height and curvature at the maximum, and one Gaussian residual part independent of these variables. These Slepian models are easy to simulate once the rather complicated space-time correlation between vertical and horizontal movements are constructed. We use the models to illustrate the statistical relation between wave asymmetry and particle orbit orientation. We also relate the orientation to the velocities of the top particle. The results are of interest in stochastic fluid dynamics.