The 12th International Conference on Hydrodynamics
18 – 23 september 2016, Egmond aan Zee, The Netherlands
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THE RESONANT PHENOMENA OF TSUNAMI WAVE RUNUP IN THE SOUTH CHINA SEA


Go-down ichd2016 Tracking Number 25

Presentation:
Session: Hydrodynamics in Ocean I
Room: Room 3
Session start: 10:30 Mon 19 Sep 2016

Xi Zhao   xzhao_2000@sjtu.edu.cn
Affifliation:

Hua Liu   hliu@sjtu.edu.cn
Affifliation:


Topics: - Hydrodynamics in ocean, coastal and estuary engineering

Abstract:

With the geological movements becoming active, the frequency of tsunami disaster is increasing in recent years. The giant events include the Chilean tsunami in 1960, the Indian Ocean tsunami in 2004 and Sendai, Japan tsunami in 2011. A risk map provided by the US Geological Survey (USGS), shows a potential tsunami earthquake fault zone in the South China Sea. The Manila trench is a high risk area of tsunami source. Once undersea earthquakes occur in this area, a tsunami will be triggered and the coasts of Hainan, Guangdong, Fujian, Taiwan provinces are threatened undoubtedly. Based on the actual terrain in the South China Sea, studies on the runup rules and the disaster mechanisms of tsunami waves is helpful on the development of South China Sea tsunami early warning system construction and potential tsunami disaster prevention and mitigation strategy. The existing researches confirmed the resonant phenomena in the tsunami runup process in coastal waters with certain profiles. The aim of this work is to investigate whether runup resonance will be induced in the south coast of China if there is a tsunami in the Manila trench. In this paper, we solve the nonlinear shallow water equations to obtain the runup amplification on a profile of 4 segments. The topography on the propagation path of tsunami in the South China Sea can be simplified to a 4-segments profile. It comprises a horizontal deep seabed, a continental foundation, a continental slope and a continental shelf from the trench to the shore. We calculate the runup amplification on some piece-wise profile and analyze the resonant phenomena of certain wave frequency. As a comparison, we simulate the runup amplification by numerical model of Boussinesq equations. The runup resonance can be obtained by the numerical simulation. On the propagation path of tsunami, the resonance effects due to the piece-wise bathymetry are investigated. The runup amplification caused by the resonance for certain wave frequency is discussed.