A vertical coordinate mapping technique for semispectral primitive equation models of oceanic circulation

Abstract

A stretched coordinate technique for semispectral hydrodynamic models is described that allows for greater flexibility in the placement of model grid points. Stretching is implemented here for the vertical coordinate of an oceanic model that employs Chebyshev polynomials to represent the vertical structure. While the method cannot yield improved accuracy for all situations, in appropriate cases it permits reduced computation for an accurate result by reducing the number of basis functions necessary for adequate resolution of the modeled fields. Some guidelines are presented for its application, along with cautions as to where the technique is disadvantageous. -from Authors