title: Acoustic multipath arrivals in the horizontal plane due to approaching nonlinear internal waves.
abstract: Simultaneous measurements of acoustic wave transmissions and a nonlinear internal wave packet approaching an along-shelf acoustic path during the Shallow Water 2006 experiment are reported. The incoming internal wave packet acts as a moving frontal layer reflecting (or refracting) sound in the horizontal plane. Received acoustic signals are filtered into acoustic normal mode arrivals. It is shown that a horizontal multipath interference is produced. This has previously been called a horizontal Lloyd's mirror. The interference between the direct path and the refracted path depends on the mode number and frequency of the acoustic signal. A mechanism for the multipath interference is shown. Preliminary modeling results of this dynamic interaction using vertical modes and horizontal parabolic equation models are in good agreement with the observed data.
authors.affiliation: Physical Ocean Science and Engineering, University of Delaware, Newark, Delaware 19716, USA. badiey@udel.edu
authors.forename: Mohsen
authors.initials: M
authors.lastname: Badiey
authors.forename: Boris G
authors.initials: BG
authors.lastname: Katsnelson
authors.forename: Ying-Tsong
authors.initials: YT
authors.lastname: Lin
authors.forename: James F
authors.initials: JF
authors.lastname: Lynch
mesh_terms: D000162:Acoustics; D008962:Models, Theoretical; D017711:Nonlinear Dynamics; D009791:Oceanography / Q000379:methods*; D012623:Seawater