Transparent lateral boundary conditions for baroclinic waves: a study of two elementary systems of equations

Transparent lateral boundary conditions are derived for two linear systems of equations which support baroclinic waves. The first consists of a two-layer model of two superposed immiscible fluids of different densities. The second consists of a multilevel model of the hydrostatic primitive equations in two (x–z) dimensions. A practical demonstration is given of the efficacy of these boundary conditions for both system of equations. First, it is shown that the boundaries are transparent to outgoing waves. Secondly, it is demonstrated that externally imposed incoming waves enter without distortion.