A range refraction parabolic equation

Application of the standard parabolic wave equation to solve real problems requires a clever selection of the reference wavenumber k0. An extended parabolic equation, having range refraction capability, is reintroduced in such a manner so as to be totally independent of k0. An already existing Implicit Finite‐Difference (IFD) model was applied to test the range refraction parabolic equation. Results compare favorably with known solutions for weakly range‐dependent environments, but yield significant corrections for propagation through strong oceanic fronts.