On the calculation of normal modes of a coupled ice-shelf/sub-ice-shelf cavity system

A corrected solution method is presented for a mathemat-ical model of wave motions in a coupled ice-shelf/sub-ice-shelf water-cavity system. The method is used to calculate the periods of the system’s normal modes, and the longest periods are shown to be significantly larger than those calculated using an existing method contain-ing errors. Highly accurate approximations of the normal-mode periods are obtained for a model involving a single non-spectral physical parameter – the shelf/cavity length.