Rip Channels and Nearshore Circulation

Results from an experimental investigation into the e ects of rip channels on the nearshore circulation system are presented The results show that periodic channels in an otherwise longshore uniform bar induce longshore pressure gradi ents that drive pairs of counter rotating circulation cells Dense measurements of wave height wave setup and induced currents are presented In addition ev idence of secondary circulation cells close to the shoreline is also given Finally the rip current is shown to contain low frequency oscillations probably due to jet instability and also tends to meander back and forth in the rip channel