Worldwide, military transportation and activities are among the least studied sources of noise pollution. The implications of a concurrent change to more powerful aircraft and increased operations for noise pollution have not been measured, leaving knowledge gaps in the ability to assess vulnerability of both people and wildlife, including Endangered, Threatened or sensitive species. The changes at NASWI are reflective of a broader national trend in military base closures and consolidation, which are likely to intensify community noise and air pollution in some areas. Consolidation of nationwide training for these aircraft to NASWI increased the fleet size by 44% (from 82 to 118 aircraft) in 2019, with corresponding increases in air carrier practice, electronic warfare training, and overall base operations. Although naval flights have been operating in the area for decades, the recent transition from Northrop Grumman EA-6B Prowler to the more powerful Boeing EA-18G Growler aircraft for electronic warfare has led to increases in the number of complaints about noise, including concern for area wildlife. Military aircraft activity in the Salish Sea, Washington State, has been increasing over the past decade due to changes in operations and training for personnel out of the Naval Air Station Whidbey Island (NASWI). Our study highlights challenges and problems in evaluating the implications of increased noise pollution from military operations, and knowledge gaps that should be prioritized with respect to understanding impacts on people and sensitive wildlife. ![]() Using a hydrophone deployed near one runway, we also detected sound signatures of aircraft at a depth of 30 m below the sea surface, with noise levels (134 ± 3 dB re 1 µPa rms) exceeding thresholds known to trigger behavioral changes in fish, seabirds, and marine mammals, including Endangered Southern Resident killer whales. Importantly, we demonstrate that the number and cumulative duration of daily overflights exceed those in a majority of studies that have evaluated impacts of noise from military aircraft worldwide. In-air noise levels (110 ± 4 dB re 20 µPa rms and 107 ± 5 dBA) exceeded known thresholds of behavioral and physiological impacts for humans, as well as terrestrial birds and mammals. A recent transition to more powerful military aircraft and a national consolidation of training operations to Whidbey Island, WA, USA, provided a unique opportunity to measure and assess both in-air and underwater noise associated with military aircraft. 3, 2012.Military operations may result in noise impacts on surrounding communities and wildlife. Gupta, "An acoustic communication based AQUA-GLOMO simulator for underwater networks," Springer Human-centric Computing and Information Sciences, vol. Considering this challenge, our chamber includes a phono-absorbing coating on the walls and floor, to be optionally complemented by a panel of the same coating material, to be installed at the water surface level.Īfter providing the details of several phono-absorbing materials to motivate our specific choice, we carry out a number of transmission experiment with EvoLogics modems, proving that our design substantially reduces the severe multi-path and thereby improves the communications quality. ![]() The chamber was designed to mitigate the extreme multi-path which, in a small chamber, makes communications unreliable. ![]() The chamber has been assembled with the objective to be of low cost and limited size: therefore, its installation fits small university laboratories that cannot afford large testing pools. In this paper, we present the design guidelines, structure and details of a small-scale, low-cost acoustic chamber for in-lab testing of underwater acoustic networks. Testing acoustic equipment before sea experiments is a necessary step, which usually requires large and expensive facilities.
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