A DEPTH-INTEGRATED EQUATION FOR LARGE SCALE MODELING OF TSUNAMI IN WEAKLY COMPRESSIBLE FLUID

Ali Abdolali, Claudia Cecioni, Giorgio Bellotti, Paolo Sammarco

Abstract


Pressure waves generated by fast seabed movement in weakly compressible sea water, namely hydro-acoustic waves travel at the sound celerity in water (about 1500 m/s). These waves are precursors of the counterpart long free-surface gravity waves and contain significant information on the tsunamigenic source. Measurement of hydro-acoustic waves can therefore anticipate the tsunami arrival and significantly enhance the promptness and accuracy of tsunami early warning systems. In this paper derivation of a novel depth-integrated numerical model for reproduction of hydroacoustic waves is presented and the application of this computationally ecient model on two devastating historical tsunamis of Mediterranean Sea in real bathymetry analyzed to reveal the eect of variable bathymetry. On the basis of the model results, some hints for deep sea observatory are given.

Keywords


Hydro-acoustic waves; Weakly compressible; Tsunami; Precursor

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References


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DOI: https://doi.org/10.9753/icce.v34.currents.9