title: Quasiplanar steep water waves.
abstract: A unique description for highly nonlinear potential water waves is suggested, where weak three-dimensional effects are included as small corrections to exact two-dimensional equations written in conformal variables. Contrary to the traditional approach, a small parameter in this theory is not a surface slope, but it is the ratio of a typical wavelength to a large transversal scale along the second horizontal coordinate. A first-order correction for the Hamiltonian functional is calculated, and the corresponding equations of motion are derived for steep water waves over an arbitrary nonuniform quasi-one-dimensional bottom profile.
authors.affiliation: Landau Institute for Theoretical Physics, 2 Kosygin Street, 119334 Moscow, Russia. ruban@itp.ac.ru
authors.forename: V P
authors.initials: VP
authors.lastname: Ruban