Effects of sediment properties on surface-generated ambient noise in a shallow ocean

Liu, Jin‐Yuan; Lin, I-Chun; Chu, Chung-Ray

doi:10.1016/j.oceaneng.2005.04.001

Cited by 4 publications

(5 citation statements)

References 13 publications

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“…Surface-generated ambient noise is likely to contaminate any signal propagating in the ocean due to its persistent existence and wide coverage in the noise spectrum [1]. Generally independent of place of measurement, the ambient noise spectrum level is highly variable due to many influencing factors such as ocean depth, bottom composition, sea state and acoustic propagation.…”

Section: Resultsmentioning

confidence: 99%

Analysis of Fluctuations in Wind Dependent Shallow Water Ambient Noise Spectrum

2007

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Section: Resultsmentioning

confidence: 99%

Analysis of Fluctuations in Wind Dependent Shallow Water Ambient Noise Spectrum

2007

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“…In the ocean, the frequency band of bubble radiation sound is particularly affected by ambient noise produced from the sea surface [19,20], ship transit noise and traffic noise [27,28,21,22,23].…”

Section: Ambient Noisementioning

confidence: 99%

“…In the ocean, ambient noise can be radiated from turbulence, surface wave agitation, thermal agitation, seismic events, rainfall, marine animals, ice sheet cracking, and shipping [16,17,18,19,20,21,22,23]. The bubble source spectrum of interest for bubbles released from the seabed (where bubbles tend to be larger than those generated by breaking ocean waves) [24,25] is usually within a frequency band from hundreds of Hz up to around 25 kHz for small/moderate-sized injection points [15,26].…”

Section: Introductionmentioning

confidence: 99%

“…The bubble source spectrum of interest for bubbles released from the seabed (where bubbles tend to be larger than those generated by breaking ocean waves) [24,25] is usually within a frequency band from hundreds of Hz up to around 25 kHz for small/moderate-sized injection points [15,26]. The frequency band is particularly affected by ambient noise produced from the sea surface [19,20], as well as ship noise [27,28,21,22,23]. Noise outside this frequency band is usually not of concern [29].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

A noise impact assessment model for passive acoustic measurements of seabed gas fluxes

White

Bull

et al. 2019

Ocean Engineering

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Accurate determination of seabed gas flux is important for understanding natural processes as well as giving confidence that the size of any leaks from marine infrastructure can be properly assessed. Acoustic methods for flux determination require a relatively quiet underwater environment, and can fail when there is too much noise from other natural or anthropogenic sources. This study applies an acoustic monitoring example of seabed gas leakage in terms of sound level intensity, to statistically assess and minimize the impact from oceanic noise on seabed acoustic experiments which require relative quiet environment. It addresses the question: how far from a source of radiated ambient noise does a recording hydrophone and location of seabed gas need to be so that acoustic methods for remotely determining gas flux are successful. We develop a model to assess impacts of ambient noise under various conditions, incorporating sound/noise sources (seabed gas leaks, sea surface agitation and shipping) and underwater acoustic propagation. The reliability of the model is tested by comparing measured seabed ambient noise in the central North Sea, and the robustness of it is verified by presenting statistical outliers and a receiver operating characteristic (ROC) curve. A range of scenarios are presented for several gas flow rates, which show the threshold of detection when the recording hydrophone is at different distances from the location of seabed gas escape, and competing noise sources (including shipping and surface waves).

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“…The depth of the transmitter was 250 m, and the depth of the first receive VLA hydrophone was 420 m. The length of the receive VLA of hydrophones is 8.1 m. The receive VLA oscillation can be resulted from the ocean dynamics. Underwater ambient noise in the communication channel can be radiated from surface wave agitation, shipping, marine animals, turbulence, etc [45,46,47,48,49,50,51,52]…”

mentioning

confidence: 99%