[H-GM22_30PO1] Geomorphology

[HGM22-P08] Field measurements on the reduction of wave height on a fringing reef: A study from the Miibaru coast, Okinawa Island

*Yu TAKEISHI¹, Hisashi AOKI², Akira MAEKADO³, Takashi HIROSE³ (1.Graduate School of Humanities and Social Sciences, University of the Ryukyus, 2.Faculty of Business Administration, Daito Bunka University, 3.Faculty of Law and Letters, University of the Ryukyus)

Keywords:Reduction of wave height, Coral reef, Fringing reef, Water depth, Okinawa Island

To investigate the relationship between reduction of wave height on a fringing reef and the water depth at the reef edge, field measurements were carried out on Miibaru coast with a fringing reef in Okinawa Island, Japan. The ratio of the shore break height (the height of final breaking waves near the shoreline) to the wave height at the reef edge, H_/H', which denotes the degree of the reduction of wave height on a reef, was found to decrease with decreasing water depth at the reef edge. This result indicates that the reduction of wave height on a reef is greatly controlled by water depth on a fringing reef.