Low-frequency Kelvin wave reflection coefficient

An analytic method is presented for determining the reflection coefficient of a low frequency Kelvin wave propagating into a semi-infinite channel. The method yields an exact expansion in frequency, which in this note is carried out to an error of order ( omega /f) super(5). Application is made to the reflection of a low frequency Kelvin wavepacket. The lowest order terms in the expansion are shown to correspond to a time lag and a distortion of the waveform. (DBO)