Penetration of the Earth's free oscillations at 54 minute period into the atmosphere

It is known that the fundamental spheroidal mode 0S2 of the Earth free oscillation with a period of about 54 min forces atmospheric oscillations. We present a certain phase relationship for components of the 0S2 multiplet, which is based on synchronous collocated microbarograph and seismograph observations. This relationship is both the first observational manifestation of the Pekeris mode of global atmospheric oscillations with the 54 min period and a further proof of the Earth's 0S2 mode penetrating into the atmosphere. We show that the linear non-dissipative model of steady forced oscillations in isothermal atmosphere at rest does not describe the penetration of the 0S2 mode into the atmosphere adequately.Key words: Meteorology and atmospheric dynamics (middle atmosphere dynamics; waves and tides)