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TECHNICAL COMMITTEE REPORT
Acoustical Oceanography
isms (Medwin and Clay, 1998; Simmonds and MacLennan, 2005). Fisheries acoustics research is particularly active, with multiple special sessions dedicated to this topic over the last decade or so. One of the goals of fisheries acoustics is to assist in making wise fisheries management decisions for the sustainable exploitation of this natural resource. Traditional fisheries acoustics approaches for quantifying fish biomass and abundance involve the use of single frequency sonars typically at frequencies much higher than the resonance fre- quency associated to the swim bladder. Recent progress in developing sea-worthy broadband sonar techniques (Stan- ton et al., 2010) has opened to the door to improved quanti- fication of fish by allowing the swim bladder resonance to be mapped. In fact, Holliday (1972) used broadband explosive acoustic sources in 1972 to very successfully map the spec- tral returns of various pelagic fish schools and compared the measured spectra to predictions based on rigorous acoustic approaches. However, there are significant modern head- aches associated to obtaining permits for use of explosive sources! Fisheries acoustics worldwide has generally been very receptive to advances in acoustics techniques and in adopting such technologies into fisheries management deci- sions.
Other acoustical approaches to quantifying fish include resonance absorption spectroscopy and the use of ocean waveguide acoustics for synoptic imaging, which takes ad- vantage of the waveguide generated by trapping sound be- tween the air-sea and ocean-seabed boundaries (Makris et al., 2006). In fact, marine ecosystem acoustics, involving the use of acoustic techniques for quantifying and monitoring entire marine ecosystems at the spatio-temporal scales on which they occur (Godo et al., 2014), is currently a growing area of research. It is anticipated that ecosystem acoustics approaches will be one of the principal tools in operational Ecosystem Based Integrated Management. The success of this approach is yet to be determined, but depends on co- operation between fisheries acoustics, physics, engineering, biology, oceanography, and ecology. This is precisely the type of interdisciplinary science that the TCAO thrives on. An entire upcoming ICES symposium (May 2015), co-spon- sored by ASA, will focus on marine ecosystem acoustics.
Although the TCAO is one of the smaller technical commit- tees within ASA, its primary strength lies in the highly in- terdisciplinary nature and impressive scope of the research performed by its members. A glance at recent recipients of the Lindsay Award, A.B. Wood Medal, and the Medwin Prize, reveals that the TCAO is home to a talented, rigorous, and gritty cohort of young scientists sustaining multifaceted careers, despite a particularly challenging funding environ- ment, and simultaneously advancing research in acoustical oceanography by building on a legacy of excellence in re- search developed by the founding members of the TCAO. As current chair of the TCAO, it has been my pleasure to see the level of involvement of these younger scientists in the affairs of the ASA, and their commitment to performing outstand- ing research in acoustical oceanography, the best possible approach to maintaining the TCAO healthy and vibrant.
Biosketch
Andone C. Lavery received the B.A. degree in mathematics from Cambridge University, U.K., in 1991 and a Ph.D. degree in physics from Cornell University in 1999. She was a Postdoctoral Scholar/Fellow from 1999 to 2002, and was hired onto the scientific staff in 2002, at the Woods Hole Oceanographic Institu- tion. Her research interests include
acoustic scattering and propagation in discrete and continu- ous random media, with a focus on marine organisms and small scale fluid processes. Dr. Lavery is a member of ASA, current chair of the Acoustical Oceanography Technical Committee, and associate editor for JASA-EL.
References
Chapman, R., and Price, A. (2011). “Low frequency deep ocean ambient noise trend in the Northeast Pacific Ocean,” Journal of the Acoustical Soci- ety of America 129(5), EL161-EL165.
Deane, G., Preisig, J., and Lavery, A.C. (2013). “The suspension of large bub- bles near the sea surface by turbulence and their role in absorbing forward- scattered sound,” IEEE Journal of Oceanic Engineering 38, 632-641.
Godo, O. R., Handegard, N. O., Browman, H. I., Macaulay, G. J., Kaartvedt, S., Giske, J., Ona, E., Huse, G., and Johnsen, E. (2014). “Marine ecosystem acoustics (MEA): quantifying processes in the sea at the spatio-temporal scales on which they occur,” ICES Journal of Marine Science 71(8), 2357– 2369.
50 | Acoustics Today | Winter 2015