Discussion of “A function to determine wavelength from deep in to shallow water based on the length of the cnoidal wave at breaking” by J.P. Le Roux

An empirical modification to the Airy equation for wave celerity reduces to the expression for solitary waves in shallow water whilst retaining its usual form for deep water. The equation yields celerities in reasonable agreement with those for cnoidal waves in intermediate water depths. In this aspect, it is similar to the work described by Le Roux [Le Roux, J.P., 2007. A function to determine wavelength from deep into shallow water based on the length of the cnoidal wave at breaking. Coastal Engineering 54, 770–774]. The empirical modification has been widely applied in computer programs over the past 30 years.