Conditional second-order short-crested water waves applied to extreme wave episodes

Abstract

A derivation of the mean second-order short-crested wave pattern and associated wave kinematics, conditional on a given magnitude of the wave crest, is presented. The analysis is based on the second-order Sharma and Dean finite-water wave theory. A comparison with a measured extreme wave profile, the Draupner New Year Wave, shows a good agreement in the mean, indicating that this second-order wave can be a good identifier of the shape and occurrence of extreme wave events. A discussion on its use as an initial condition for a fully nonlinear three-dimensional surface wave analysis is given. © 2005 Cambridge University Press.