This study is part of the University of Hawaii at Manoa’s HIREEF 2 project and aims to analyze the breaking behavior of tsunami waves over a reef shape similar to the ones present on tropical islands like Hawaii. In addition, energy dissipation due to bottom roughness was investigated and proven to be significant. When roughness was in the zone before breaking, waves were smaller, broke sooner, and crashed sooner than waves that propagated over roughness which had been placed after breaking. When looking at breaking characteristics in comparison to previous research where only a mild slope was considered, the waves in this experiment had a higher breaking index (wave height at breaking/water depth at breaking) and a lower water depth at breaking due to the geometry of the bottom surface, indicating that bathymetry plays a role in wave breaking. In the future, better understanding of the breaking behavior and energy dissipation of tsunami waves due to roughness and reef geometry will lead to more accurate numerical models that can then be used as engineering tools to save both infrastructure and lives in tsunami hazard zones.
Kimberly J. Quesnel
California Polytechnic State University, San Luis Obispo
REU Institution: Oregon State University
Principle Investigators: Dr. Ian Robertson, Dr. Ronald Riggs, Dr. Kwok Fai Cheung
Graduate Student Advisor: Pablo Duarte Quiroga
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