Wind-driven Currents in a Sea with a Variable Eddy Viscosity Calculated via a Sinc-galerkin Technique

The Sinc-Galerkin method is presented as a new and potentially useful extension of the spectral method in numerical oceanography. To describe and illustrate the technique , a Sinc-Galerkin procedure is used to infer the sensitivity of wind-driven subsur-face currents in coastal regions and semi-enclosed seas when the vertical eddy viscosity coeecient is represented as a continuously diierentiable function of depth. Problems with exact solutions are used to explore the accuracy and exponential convergence of expansions using composite translated sinc functions as a basis set. To illustrate the essential idea, we describe applications of the Sinc-Galerkin technique to modiications of the Ekman wind-drift current problem.