Tidal Eulerian Residual Currents over a Slope: Analytical and Numerical Frictionless Models

Abstract

Abstract The Eulerian residual tidal currents generated over a continental slope are examined. Using the assumption of a Poincare wave, the linear frictionless solution of a semidiurnal tidal wave propagating from the deep ocean to a constant depth continental shelf has been developed for any angle of incidence of the oceanic wave on the slope. Two cases are investigated: the limiting case of a boundless shelf is first solved, then the shelf is considered as a region bounded by a coast. As a first step, the linear analytical solution over an idealized linear slope is thus established. Then, the linear analytical formulations are tested as boundary and initial conditions of a numerical model in which the advection terms are linearized. The preponderant residual current expected near the shelf break is thus effectively reproduced. The nonlinear numerical features observed in the surroundings of the top of the slope are verified to agree with the analytical expressions derived from linear solutions. In addit...