Theory on the energy of atmospheric Lamb waves: Proposal of Infrasound Magnitude

Kensuke Nakajima

Presentation information

[J] Oral

M (Multidisciplinary and Interdisciplinary) » M-TT Technology & Techniques

[M-TT52] Brand-new scope of coupling geophysics being established by infrasound and associated waves

convener:Masa-yuki Yamamoto(Department of systems engineering, Kochi University of Technology), Nobuo Arai(Disaster Mitigation Research Center, Nagoya University), Mie Ichihara(Earthquake Research Institute, University of Tokyo), Takayuki Otsu(Japan Weather Association)

[MTT52-10] Theory on the energy of atmospheric Lamb waves: Proposal of Infrasound Magnitude

★Invited Papers

*Kensuke Nakajima¹ (1.Department of Earth and Planetary Sciences,Flculty of Sciences,Kyushu University)

Keywords:tsunami, atmospheric lamb wagves, infrasound, micro barometric observations

Major tsunamis excite significant atmospheric Lamb waves, i.e. low frequency ground trapped atmospheric waves that propagate with acoustic wave speed, and their signals can be useful for the inversion of tsunami sources (e.g. Arai et al 2011; Mikumo et al 2008). Here I will discuss (i) the result of numerical experiments on the response of compressible atmosphere to the vertical motion of ground surface representing tsunamis, (ii) its theoretical interpretation, and (iii) propose "infrasound magnitude" that can be determined quickly using microbarometric waveform at a single observation point and useful for estimating the magnitude of tsunamis.