title: Toward ocean attenuation tomography: Determining acoustic volume attenuation coefficients in seawater using eigenray amplitudes.
abstract: A deep-water experiment in the Pacific made in situ measurements of the volume attenuation coefficients of sea water in the mid-frequency range. The frequency, temperature, salinity, pH, and pressure dependent seawater attenuation coefficients were determined using a vertical line array that received and identified over 2000 unique paths from 1200 mid-frequency 3-9 kHz LFM source transmissions at a convergence zone range and depth up to 400 m. The results show no change in attenuation coefficients in this band compared to estimates from 30-year-old models previously determined from a combination of long-range ocean acoustic and laboratory experiments. The inversion also explores the feasibility of ocean acoustic attenuation tomography to further separate the depth-dependent chemical components responsible for the total attenuation loss through by isolating a group of deep-water refracting acoustic paths.
authors.affiliation: Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla California 92093-0238, USA jtippman@ucsd.edu, bsarkar@ucsd.edu, cmverlin@ucsd.edu, whodgkiss@ucsd.edu, wkuperman@ucsd.edu.
authors.forename: J D
authors.initials: JD
authors.lastname: Tippmann
authors.affiliation: Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla California 92093-0238, USA jtippman@ucsd.edu, bsarkar@ucsd.edu, cmverlin@ucsd.edu, whodgkiss@ucsd.edu, wkuperman@ucsd.edu.
authors.forename: J
authors.initials: J
authors.lastname: Sarkar
authors.affiliation: Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla California 92093-0238, USA jtippman@ucsd.edu, bsarkar@ucsd.edu, cmverlin@ucsd.edu, whodgkiss@ucsd.edu, wkuperman@ucsd.edu.
authors.forename: C M A
authors.initials: CM
authors.lastname: Verlinden
authors.affiliation: Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla California 92093-0238, USA jtippman@ucsd.edu, bsarkar@ucsd.edu, cmverlin@ucsd.edu, whodgkiss@ucsd.edu, wkuperman@ucsd.edu.
authors.forename: W S
authors.initials: WS
authors.lastname: Hodgkiss
authors.affiliation: Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla California 92093-0238, USA jtippman@ucsd.edu, bsarkar@ucsd.edu, cmverlin@ucsd.edu, whodgkiss@ucsd.edu, wkuperman@ucsd.edu.
authors.forename: W A
authors.initials: WA
authors.lastname: Kuperman