Variability in Anthropogenic Underwater Noise Due to Bathymetry and Sound Speed Characteristics

Journal of Marine Science and Engineering

Caitlin O’Neill¹  Svein Vagle¹  Rianna E. Burnham¹  Harald Yurk² 

[1] Institute of Ocean Sciences, Fisheries and Oceans Canada (DFO), Sidney, BC V8L 4B2, Canada;Pacific Science Enterprise Centre, Fisheries and Oceans Canada (DFO), Vancouver, BC V7V 1H2, Canada;

关键词: anthropogenic noise;    passive acoustic monitoring;    sound speed profiles;    natural variability;    ray tracing models;    transmission losses;   

DOI  :  10.3390/jmse9101047

来源: DOAJ

【 摘 要 】

Oceanic acoustic environments are dynamic, shaped by the spatiotemporal variability in transmission losses and sound propagation pathways of natural and human-derived noise sources. Here we used recordings of an experimental noise source combined with transmission loss modeling to investigate changes in the received levels of vessel noise over space and time as a result of natural water column variability. Recordings were made in the Juan de Fuca Strait, on the west coast of Vancouver Island, a biologically productive coastal region that hosts several cetacean species. Significant variability in noise levels was observed due to changing water masses, tied to seasonal temperature variation and, on a finer scale, tidal movements. Comparisons of interpreted received noise levels through the water column indicated that vessel noise recorded by bottom-stationed monitoring devices might not accurately represent those received by whales in near-surface waters. Vertical and temporal differences of 3–5 dB were commonly observed in both the recorded and modeled data. This has implications in estimating the success of noise mitigation measures, and our understanding of the change in sound fields experienced by target species for conservation.

【 授权许可】

Unknown