Particle Image Velocimetry (PIV) measurements of the flow induced by breaking waves over a smooth steep slope of 1/15 were performed. Five cases of incoming regular waves were tested. Upstream of wave breaking, the induced oscillatory flow was not sinusoidal in time as the wave crests became steeper and the troughs wider. The profiles of the period-mean velocity showed the existence of a return current. Outside the surf zone, the current magnitude decreases linearly with increasing distance from the free surface, but it is influenced by the parabolic nature of the surf-zone undertow just upstream of the breaking position.
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