Abstract
Acoustic measurements of near-surface bubbles generated by breaking waves were made off Whidbey Island, Puget Sound, Washington. A limited amount of data was also gathered in the open ocean off the coast of Washington. The intent of these measurements was to delineate the role of near-surface bubbles in surface backscattering, forward loss, and ambient noise at high frequencies. High resolution vertical incidence backscatter was the principal method used for determining the near-surface volume scattering strength profile attributable to bubbles. For one of the data sets low grazing angle forward loss measurements were interspersed with the vertical incidence measurements. It was clear from the vertical incidence measurements that bubbles are acoustically observable at wind speeds as low as 3 m/s and that for wind speeds greater than about 5–6 m/s the surface forward loss can become quite large (>10 dB).
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References
P. D. Koenigs, J. M. Monti, B.Nutzel and H. Herwig, The Influence of Bubbles on Sea Surface BackscatterMeasurements, NUSCTD 7811 (also FWG-Bericht 1986-9), Naval Underwater Systems Center, New London, 26 October 1986.
D. Middleton, AcousticScattering from Composite Wind-Wave Surfaces II: Backscatter Cross Sections andDoppler Effects at HighFrequencies and Small Angles for Bubble-Free Regimes, NUSC
TD 7 635, NavalUnderwater Systems Center, New London, 22 July 1986.
S. T. McDaniel and A. D. Gorman,Acoustic and Radar Sea Surface Backscatter, J. Geophys. Res. 87, 4127–4136 (1982).
E. I. Thorsos, SurfaceForward Scattering and Reflection, APL-UW 7–83, Applied Physics Laboratory, University ofWashington, May 1984.
E. I. Thorsos, HighFrequency Surface Forward Scattering Measurements, presented at the 108th meeting ofthe ASA, 8–12 October,1984 (J. Acoust. Soc. Am. Suppl. 1, 76, S55(1984)).
D. M. Farmer and D. D. Lemon,The Influence of Bubbles on Ambient Noise in the Ocean at High Wind Speeds, J. Phys.Ocean. 14, 1762–1778 (1984).
J. Wu, Bubble Populationsand Spectra in Near-Surface Ocean: Summary and Review of Field Measurements, J.Geophys. Res. 86, 457–463 (1981).
H. Medwin, In-Situ AcousticMeasurements of Bubble Populations in Coastal Waters, J. Geophys. Res. 75, 599–611(1970).
S. O. McConnell, RemoteSensing of the Air-Sea Interface Using Microwave Acoustics, Proceedingsof OCEANS `83, 85-92, 29 August-1 September (1983).
F. MacIntyre, On reconcilingoptical and acoustical bubble spectra in the mixed layer, 75–94, in OceanicWhitecaps (E. C. Monahan and G. MacNiocaill (eds.)), D. Reidel PublishingCo., 1986.
S. A. Thorpe, On the Cloudsof Bubbles Formed by Breaking Wind-Waves in Deep Water, and Their Role in Air-Sea GasTransfer, Phil. Trans. Roy. Soc. Lond. A 304155–210 (1982).
B. R. Kerman, Distributionof Bubbles Near the Ocean Surface, Atmos.-Ocean24, 169–188 (1986).
C. Devin, Survey of Thermal,Radiation, and Viscous Damping of Pulsating Air Bubbles in Water, J. Acoust. Soc.Am. 31, 1654–1667 (1959).
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© 1988 Kluwer Academic Publishers
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McConnell, S.O. (1988). Acoustic Measurements of Bubble Densities at 15–50 kHz. In: Kerman, B.R. (eds) Sea Surface Sound. NATO ASI Series, vol 238. Springer, Dordrecht. https://doi.org/10.1007/978-94-009-3017-9_18
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DOI: https://doi.org/10.1007/978-94-009-3017-9_18
Publisher Name: Springer, Dordrecht
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