Waves on a shearing current: a uniformly valid asymptotic solution

Abstract

AbstractA uniformly valid asymptotic solution for waves on a shearing current is presented. This solution is more general than the previous WKB solutions because it is valid at and near a caustic. Far from the caustic line, the solution reduces to the WKB solution. It predicts that an incident wave will be reflected from a straight caustic with the same amplitude and a ½π phase shift.