Reflection of low-frequency equatorial waves at arbitrary western boundaries

Procedures are developed for calculating effects of western boundaries of arbitrary geometry on low-frequency equatorial waves. We show that the mass flux incident at the coast is all returned eastward by equatorial Kelvin waves. Short Rossby waves generated as part of the reflection serve only to redistribute mass along the coast. For the case of a uniformly sloping coast we present formulae and graphical results for the amplitude of the equatorial Kelvin wave reflected at the coast due to incident free Rossby waves. Results are shown to depend on the single parameter "Yw, where l' is the slope of the coast and w is the nondimensional frequency. Similar results are presented for a special class of forced problems. Possible implications for equatorial currents in the Indian Ocean are discussed.