[MIS15-P02] Theoretical consideration of the excitation of atmospheric Lamb waves by tsunamis
Keywords:Lamb waves, tsunamis, atmospheric waves
We solve two-dimensional linearized compressible equations of isothermal atmosphere forced by a prescribed evolution of vertical flow at the bottom simulating the effect of tsunamis. The computational domain covers 2000km horizontally and 100km vertically, whose upper 20km is the sponge layer. Two kinds of vertical flow are considered. The first one is a space-time Gaussian pulse simulating a sea surface rise following a fault motion, whose characteristic time is varied from 10 s to 300 s. The second considers horizontally moving Gaussian sea surface rise simulating the propagation of tsunami wave, whose propagation speed is varied from 25m/s to 300m/s. The basic equations are discretized employing spmodel (Takehiro et al 2013). Results will be presented in the presentation and discussed focusing mainly the excitation of Lamb waves, which has no vertical motion in the modal structure, are excited by the vertical displacement at the bottom boundary.
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