Regulating Ocean Noise: A Collaborative and Creative International Approach

2007 ◽  
Author(s):  
Helen Andrews
Keyword(s):  
Ocean Noise

Extracting Coherent Structure from High Frequency Ocean Noise

2003 ◽  
Author(s):  
Hee C. Song ◽  
W. S. Hodgkiss ◽  
W. A. Kuperman ◽  
Philippe Roux
Keyword(s):  
Coherent Structure ◽  
High Frequency ◽  
Ocean Noise

scholarly journals Bio-Inspired Covert Active Sonar Strategy

Sensors ◽  
2018 ◽  
Vol 18 (8) ◽  
pp. 2436 ◽  
Author(s):  
Jiajia Jiang ◽  
Xianquan Wang ◽  
Fajie Duan ◽  
Chunyue Li ◽  
Xiao Fu ◽  
...  
Keyword(s):  
Marine Mammals ◽  
Estimation Method ◽  
Sperm Whale ◽  
Waveform Design ◽  
Velocity Estimation ◽  
Estimation Methods ◽  
Range Resolution ◽  
Active Sonar ◽  
Ocean Noise ◽  
Underwater Target

The covertness of the active sonar is a very important issue and the sonar signal waveform design problem was studied to improve covertness of the system. Many marine mammals produce call pulses for communication and echolocation, and existing interception systems normally classify these biological signals as ocean noise and filter them out. Based on this, a bio-inspired covert active sonar strategy was proposed. The true, rather than man-made sperm whale, call pulses were used to serve as sonar waveforms so as to ensure the camouflage ability of sonar waveforms. A range and velocity measurement combination (RVMC) was designed by using two true sperm whale call pulses which had excellent range resolution (RR) and large Doppler tolerance (DT). The range and velocity estimation methods were developed based on the RVMC. In the sonar receiver, the correlation technology was used to confirm the start and end time of sonar signals and their echoes, and then based on the developed range and velocity estimation method, the range and velocity of the underwater target were obtained. Then, the RVMC was embedded into the true sperm whale call-train to improve the camouflage ability of the sonar signal-train. Finally, experiment results were provided to verify the performance of the proposed method.

Tomographic inversion of measured cross-correlation functions of ocean noise in shallow water using ray theory

2016 ◽  
Vol 62 (4) ◽  
pp. 436-446 ◽  
Author(s):  
V. V. Goncharov ◽  
A. S. Shurup ◽  
O. A. Godin ◽  
N. A. Zabotin ◽  
A. I. Vedenev ◽  
...  
Keyword(s):  
Shallow Water ◽  
Correlation Functions ◽  
Cross Correlation ◽  
Ray Theory ◽  
Tomographic Inversion ◽  
Ocean Noise

The impacts of anthropogenic ocean noise on cetaceans and implications for management

2007 ◽  
Vol 85 (11) ◽  
pp. 1091-1116 ◽  
Author(s):  
L.S. Weilgart
Keyword(s):  
Oil And Gas ◽  
Synergistic Effects ◽  
Noise Pollution ◽  
Population Level ◽  
Seismic Exploration ◽  
Foraging Efficiency ◽  
Cetacean Species ◽  
Ocean Noise ◽  
Beaked Whales ◽  
Noise Impacts

Ocean noise pollution is of special concern for cetaceans, as they are highly dependent on sound as their principal sense. Sound travels very efficiently underwater, so the potential area impacted can be thousands of square kilometres or more. The principal anthropogenic noise sources are underwater explosions (nuclear and otherwise), shipping, seismic exploration by mainly the oil and gas industries, and naval sonar operations. Strandings and mortalities of especially beaked whales (family Ziphiidae) have in many cases been conclusively linked to noise events such as naval maneuvers involving tactical sonars or seismic surveys, though other cetacean species may also be involved. The mechanisms behind this mortality are still unknown, but are most likely related to gas and fat emboli at least partially mediated by a behavioral response, such as a change in diving pattern. Estimated received sound levels in these events are typically not high enough to cause hearing damage, implying that the auditory system may not always be the best indicator for noise impacts. Beaked whales are found in small, possibly genetically isolated, local populations that are resident year-round. Thus, even transient and localized acoustic impacts can have prolonged and serious population consequences, as may have occurred following at least one stranding. Populations may also be threatened by noise through reactions such as increased stress levels, abandonment of important habitat, and “masking” or the obscuring of natural sounds. Documented changes in vocal behavior may lead to reductions in foraging efficiency or mating opportunities. Responses are highly variable between species, age classes, behavioral states, etc., making extrapolations problematic. Also, short-term responses may not be good proxies of long-term population-level impacts. There are many examples of apparent tolerance of noise by cetaceans, however. Noise can also affect cetaceans indirectly through their prey. Fish show permanent and temporary hearing loss, reduced catch rates, stress, and behavioral reactions to noise. Management implications of noise impacts include difficulties in establishing “safe” exposure levels, shortcomings of some mitigation tools, the need for precaution in the form of reducing noise levels and distancing noise from biologically important areas, and the role of marine protected areas and monitoring in safeguarding cetaceans especially from cumulative and synergistic effects.

OCEAN NOISE BUDGETS

Bioacoustics ◽  
2008 ◽  
Vol 17 (1-3) ◽  
pp. 133-136 ◽  
Author(s):  
JAMES H. MILLER ◽  
JEFFREY A. NYSTUEN ◽  
DAVID L. BRADLEY
Keyword(s):  
Ocean Noise

scholarly journals The first Mares Conference on Marine Ecosystems Health and Conservation 2014: key messages and outcomes

2015 ◽  
Author(s):  
Tim Deprez ◽  
Magda Vincx ◽  
Adelino V.M. Canario ◽  
Karim Erzini ◽  
Katherine Brownlie
Keyword(s):  
Climate Change ◽  
Biological Invasions ◽  
Salt Marshes ◽  
Marine Mammals ◽  
Climate Adaptation ◽  
Marine Ecosystems ◽  
Taxonomic Composition ◽  
Marine Biodiversity ◽  
Intergovernmental Panel ◽  
Ocean Noise

The first Mares Conference on Marine Ecosystems Health and Conservation was a successful event organized by the MARES doctoral programme bringing together over 150 researchers in Olhão, Portugal from November 17th to 21st 2014. The conference was opened by Prof. Dr. Hans-Otto Pörtner, whose keynote address focused on a sectoral analysis by the Intergovernmental Panel on Climate Change Fifth Assessment Report (IPCC AR5) on the impacts of climate change on the world’s oceans. The first session on “Future oceans” was opened with a talk by Dr. Frank Melzner highlighting the problems calcifying invertebrates face in the warmer, more acidic and hypoxic waters. Other presenters dealt with changing global diversity patterns, ocean acidification, and the loss the genetic diversity. The second session on “Natural resources” was opened by Dr. Rainer Froese, who focused on whether or not the oceans can feed humanity. This talk introduced other contributions in the session, dealing with fisheries issues and Marine Protected Areas, as well as problems with proper identifications of species used for economic purposes. “Biodiversity effects” was the scope of the third session opened by a talk on oxygenation and marine biodiversity challenges in the 21st Century by Prof. Lisa Levin. Rapid ocean deoxygenation is a process which is currently less investigated but which has considerable effects on body size, taxonomic composition, habitat heterogeneity, and nutrient cycling. The following presentations focused on other factors having a strong effect on marine biodiversity, ranging from the harvesting of algae to the fragmentation of ecosystems. The fourth session addressed “Biological invasions”. Dr. Gregory Ruiz discussed biological invasions in North American marine ecosystems and the need for constant monitoring, and the use of a dynamic and multi-vector approach. Problems with invasive species in European waters were addressed with examples from the Baltic Sea, the North Sea, and the Mediterranean Sea. The fifth session on “Ocean Noise” was opened by Prof. Peter Tyack with a talk on the effects of anthropogenic sound on marine mammals. Although ocean noise issues are often linked to marine mammals, the effects of sound related to marine constructions on fish behaviour, nicely illustrated that ocean noise is a factor with a much broader impact than expected. The last session of the first Mares Conference dealt with “Habitat loss”. Dr. Michael Beck focused on this topic with his talk on ‘Building Coastal Resilience for Climate Adaptation and Risk Reduction’. Talks in the session ranged from the use of telemetry as a tool to monitor species in changed habitats, to cases dealing with sea level rise related problems in for example salt-marshes. The first Mares Conference offered a broad range of oral and poster presentations, as well as digital presentations. The poster and digital object presentations included over 100 contributions.

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