Comparative computational performance of two different techniques for calculation of the sea surface height in a climate ocean model

Abstract

Abstract A modern trend in computational ocean modelling is based on an implicit calculation of the sea surface height, whereby a diagnostic equation is solved. In deriving this equation, in the INMCM5 climate model a time-stepping scheme used, where the stage of adjustment of the Coriolis force to the barotropic gradient is modeled separately, thereby leading to a two-dimensional system of equations with three independent variables. In this paper, an approach to derivation of the sea surface height equation in the climate ocean model is proposed, which allows a reduction of the independent variables from three to one. The computational efficiency of both methods is compared using an analytical solution for the equatorial baroclinic Kelvin wave as a test.