A numerical model for ocean ultra-low frequency noise : wave-generated acoustic-gravity and Rayleigh modes
The generation of ultra-low frequency acoustic noise (0.1 to 1 Hz) by the nonlinear interaction of ocean surface gravity waves is well established. More controversial are the quantitative theories that attempt to predict the recorded noise levels and their variability. Here a single theoretical fram...
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ftird:oai:ird.fr:fdi:010061504 2023-05-15T17:02:06+02:00 A numerical model for ocean ultra-low frequency noise : wave-generated acoustic-gravity and Rayleigh modes Ardhuin, F. Lavanant, T. Obrebski, M. Marie, L. Royer, J. Y. d'Eu, J. F. Howe, B. M. Lukas, R. Aucan, Jerôme 2013 http://www.documentation.ird.fr/hor/fdi:010061504 EN eng http://www.documentation.ird.fr/hor/fdi:010061504 oai:ird.fr:fdi:010061504 Ardhuin F., Lavanant T., Obrebski M., Marie L., Royer J. Y., d'Eu J. F., Howe B. M., Lukas R., Aucan Jerôme. A numerical model for ocean ultra-low frequency noise : wave-generated acoustic-gravity and Rayleigh modes. Journal of the Acoustical Society of America, 2013, 134 (4), p. 3242-3259. text 2013 ftird 2020-08-21T06:54:02Z The generation of ultra-low frequency acoustic noise (0.1 to 1 Hz) by the nonlinear interaction of ocean surface gravity waves is well established. More controversial are the quantitative theories that attempt to predict the recorded noise levels and their variability. Here a single theoretical framework is used to predict the noise level associated with propagating pseudo-Rayleigh modes and evanescent acoustic-gravity modes. The latter are dominant only within 200 m from the sea surface, in shallow or deep water. At depths larger than 500 m, the comparison of a numerical noise model with hydrophone records from two open-ocean sites near Hawaii and the Kerguelen islands reveal: (a) Deep ocean acoustic noise at frequencies 0.1 to 1 Hz is consistent with the Rayleigh wave theory, in which the presence of the ocean bottom amplifies the noise by 10 to 20 dB; (b) in agreement with previous results, the local maxima in the noise spectrum support the theoretical prediction for the vertical structure of acoustic modes; and (c) noise level and variability are well predicted for frequencies up to 0.4 Hz. Above 0.6 Hz, the model results are less accurate, probably due to the poor estimation of the directional properties of wind-waves with frequencies higher than 0.3 Hz. Text Kerguelen Islands IRD (Institute de recherche pour le développement): Horizon Kerguelen Kerguelen Islands |
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The generation of ultra-low frequency acoustic noise (0.1 to 1 Hz) by the nonlinear interaction of ocean surface gravity waves is well established. More controversial are the quantitative theories that attempt to predict the recorded noise levels and their variability. Here a single theoretical framework is used to predict the noise level associated with propagating pseudo-Rayleigh modes and evanescent acoustic-gravity modes. The latter are dominant only within 200 m from the sea surface, in shallow or deep water. At depths larger than 500 m, the comparison of a numerical noise model with hydrophone records from two open-ocean sites near Hawaii and the Kerguelen islands reveal: (a) Deep ocean acoustic noise at frequencies 0.1 to 1 Hz is consistent with the Rayleigh wave theory, in which the presence of the ocean bottom amplifies the noise by 10 to 20 dB; (b) in agreement with previous results, the local maxima in the noise spectrum support the theoretical prediction for the vertical structure of acoustic modes; and (c) noise level and variability are well predicted for frequencies up to 0.4 Hz. Above 0.6 Hz, the model results are less accurate, probably due to the poor estimation of the directional properties of wind-waves with frequencies higher than 0.3 Hz. |
format |
Text |
author |
Ardhuin, F. Lavanant, T. Obrebski, M. Marie, L. Royer, J. Y. d'Eu, J. F. Howe, B. M. Lukas, R. Aucan, Jerôme |
spellingShingle |
Ardhuin, F. Lavanant, T. Obrebski, M. Marie, L. Royer, J. Y. d'Eu, J. F. Howe, B. M. Lukas, R. Aucan, Jerôme A numerical model for ocean ultra-low frequency noise : wave-generated acoustic-gravity and Rayleigh modes |
author_facet |
Ardhuin, F. Lavanant, T. Obrebski, M. Marie, L. Royer, J. Y. d'Eu, J. F. Howe, B. M. Lukas, R. Aucan, Jerôme |
author_sort |
Ardhuin, F. |
title |
A numerical model for ocean ultra-low frequency noise : wave-generated acoustic-gravity and Rayleigh modes |
title_short |
A numerical model for ocean ultra-low frequency noise : wave-generated acoustic-gravity and Rayleigh modes |
title_full |
A numerical model for ocean ultra-low frequency noise : wave-generated acoustic-gravity and Rayleigh modes |
title_fullStr |
A numerical model for ocean ultra-low frequency noise : wave-generated acoustic-gravity and Rayleigh modes |
title_full_unstemmed |
A numerical model for ocean ultra-low frequency noise : wave-generated acoustic-gravity and Rayleigh modes |
title_sort |
numerical model for ocean ultra-low frequency noise : wave-generated acoustic-gravity and rayleigh modes |
publishDate |
2013 |
url |
http://www.documentation.ird.fr/hor/fdi:010061504 |
geographic |
Kerguelen Kerguelen Islands |
geographic_facet |
Kerguelen Kerguelen Islands |
genre |
Kerguelen Islands |
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Kerguelen Islands |
op_relation |
http://www.documentation.ird.fr/hor/fdi:010061504 oai:ird.fr:fdi:010061504 Ardhuin F., Lavanant T., Obrebski M., Marie L., Royer J. Y., d'Eu J. F., Howe B. M., Lukas R., Aucan Jerôme. A numerical model for ocean ultra-low frequency noise : wave-generated acoustic-gravity and Rayleigh modes. Journal of the Acoustical Society of America, 2013, 134 (4), p. 3242-3259. |
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1766055341521371136 |