title: Mesoscale variations in acoustic signals induced by atmospheric gravity waves.
abstract: The results of acoustic tomographic monitoring of the coherent structures in the lower atmosphere and the effects of these structures on acoustic signal parameters are analyzed in the present study. From the measurements of acoustic travel time fluctuations (periods 1 min-1 h) with distant receivers, the temporal fluctuations of the effective sound speed and wind speed are retrieved along different ray paths connecting an acoustic pulse source and several receivers. By using a coherence analysis of the fluctuations near spatially distanced ray turning points, the internal wave-associated fluctuations are filtered and their spatial characteristics (coherences, horizontal phase velocities, and spatial scales) are estimated. The capability of acoustic tomography in estimating wind shear near ground is shown. A possible mechanism describing the temporal modulation of the near-ground wind field by ducted internal waves in the troposphere is proposed.
authors.affiliation: Obukhov Institute of Atmospheric Physics, Moscow, Russia.
authors.forename: Igor
authors.initials: I
authors.lastname: Chunchuzov
authors.forename: Sergey
authors.initials: S
authors.lastname: Kulichkov
authors.forename: Vitaly
authors.initials: V
authors.lastname: Perepelkin
authors.forename: Astrid
authors.initials: A
authors.lastname: Ziemann
authors.forename: Klaus
authors.initials: K
authors.lastname: Arnold
authors.forename: Anke
authors.initials: A
authors.lastname: Kniffka
mesh_terms: D000162:Acoustics; D001274:Atmospheric Pressure; D006112:Gravitation; D008962:Models, Theoretical; D009038:Motion; D012815:Signal Processing, Computer-Assisted; D013016:Sound; D013018:Sound Spectrography; D013997:Time Factors; D014054:Tomography / Q000379:methods; D014919:Wind