Underwater Assessment of Anthropogenic Noise Sources Using a Field Recording Method

2018 ◽  
Vol 104 (1) ◽  
pp. 13-24
Author(s):  
Alfio Yori Fernandez
Keyword(s):  
Anthropogenic Noise ◽  
Noise Sources ◽  
Field Recording ◽  
Recording Method

Capability of low-temperature SQUID for transient electromagnetics under anthropogenic noise conditions

Geophysics ◽  
2018 ◽  
Vol 83 (6) ◽  
pp. E371-E383 ◽  
Author(s):  
Raphael Rochlitz ◽  
Matthias Queitsch ◽  
Pritam Yogeshwar ◽  
Thomas Günther ◽  
Andreas Chwala ◽  
...  
Keyword(s):  
Low Temperature ◽  
Quantum Interference ◽  
High Sensitivity ◽  
Low Noise ◽  
Induction Coil ◽  
Anthropogenic Noise ◽  
Data Sets ◽  
Noise Sources ◽  
Data Inversion ◽  
Combined Application

Transient electromagnetics (TEM) is a well-established method for mineral, groundwater, and geothermal exploration. Superconducting quantum interference device (SQUID)-based magnetic-field receivers used for TEM have quantitative advantages and higher sensitivity compared with commonly used induction coils. Special applications are deep soundings with target depths [Formula: see text] and settings with conductive overburden. However, SQUIDs have rarely been applied for TEM measurements in environments with significant anthropogenic noise. We compared a low-temperature SQUID with a commercially available induction coil in an area affected by anthropogenic noise. We acquired four fixed-loop data sets with totally 61 receiver stations close to Bad Frankenhausen, Germany. The high sensitivity of the SQUID enables low noise levels, which lead to longer high-quality transient data compared with the induction coil. The effect of anthropogenic and natural noise sources is more critical for the coil than for the SQUID data. In the vicinity of the transmitter loop, systematic distortion of the coil signals occurs at early times, most probably caused by sferic interferences. We have developed 1D inversion results of both receivers that matched well in general. However, the SQUID-based models were more consistent and showed greater depths of investigation. This led to a superior resolution of deeper layers and even enabled a potential detection of thin conducting targets at up to a 500 m depth. Moreover, we find that the SQUID data inversion revealed multidimensional effects within the conductive overburden. In this regard, we applied forward modeling to analyze systematic differences between inversion results of SQUID and coil data. We determine that low-temperature SQUIDs have the potential to significantly improve the reliability of subsurface models in suburban environments. Nevertheless, we recommend combined application of both types of receivers.

scholarly journals Underwater noise in the Slovenian Sea

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Andreja Popit
Keyword(s):  
Wind Speed ◽  
Statistical Methods ◽  
Acoustic Propagation ◽  
Anthropogenic Noise ◽  
Underwater Noise ◽  
Noise Levels ◽  
Marine Strategy Framework Directive ◽  
Noise Sources ◽  
The Eu

Abstract Continuous underwater noise has been monitored in the Slovenian sea near the lighthouse foundation at Debeli Rtič since February 2015, according to the EU Marine Strategy Framework Directive (MSFD). Anthropogenic noise sources (e.g. seawater densities, dredging activities and cleaning of the seafloor) and meteorological noise sources (e.g. wind speed and precipitation) were analysed in relation to the measured underwater noise levels using several graphical and statistical methods. The results of this study showed that average equivalent continuous underwater noise levels were, by 11 dB (L eq,63 Hz) and 5 dB (L eq,125 Hz), higher in the intervals when dredging activities took place than in the intervals when these activities were absent. Variation in underwater noise levels was partly related to the variation of the ship densities, which could be explained by the relatively small acoustic propagation in the shallow seawater. Precipitation level did not indicate any significant association with the variations in continuous underwater noise levels, though some larger deviations in the wind speed were found to be associated with the larger fluctuations in continuous underwater noise levels.

scholarly journals Validation of the Tranquillity Rating Prediction Tool (TRAPT): comparative studies in UK and Hong Kong

Noise Mapping ◽  
2017 ◽  
Vol 4 (1) ◽  
pp. 67-74 ◽  
Author(s):  
Greg Watts ◽  
Lawal Marafa
Keyword(s):  
Hong Kong ◽  
Urban Areas ◽  
Video Recording ◽  
Mainland China ◽  
Anthropogenic Noise ◽  
Prediction Tool ◽  
Noise Sources ◽  
Rating Prediction ◽  
The Uk ◽  
The Impact

AbstractThe Tranquillity Rating Prediction Tool (TRAPT) has been used to make predictions of the quality of tranquility in outdoor urban areas using two significant factors i.e. the average level of anthropogenic noise and the percentage of natural features in view. The method has a number of applications including producing tranquillity contours that can inform decisions regarding the impact of new anthropogenic noise sources or developments causing visual intrusion. The method was intended for use in mainly outdoor areas and yet was developed using responses from UK volunteers to video clips indoors. Because the volunteers for this study were all UK residents it was important to calibrate responses for other ethnic groups who may respond differently depending on cultural background. To address these issues further studies were performed in Hong Kong using the same video recording played back under the same conditions as the study in the UK. The HK study involved recruiting three groups i.e. residents from Hong Kong, Mainland China and a diverse group from 16 different nations. There was good agreement between all these groups with average tranquillity ratings for the different locations differing by less than one scale point in most cases.

scholarly journals The importance of invertebrates when considering the impacts of anthropogenic noise

2014 ◽  
Vol 281 (1776) ◽  
pp. 20132683 ◽  
Author(s):  
Erica L. Morley ◽  
Gareth Jones ◽  
Andrew N. Radford
Keyword(s):  
Anthropogenic Noise ◽  
Future Research ◽  
Behavioural Plasticity ◽  
Evolutionary Adaptation ◽  
Noise Sources ◽  
Individual Behaviour ◽  
Natural Noise ◽  
Global Pollutant ◽  
The Impact ◽  
Exclusive Focus

Anthropogenic noise is now recognized as a major global pollutant. Rapidly burgeoning research has identified impacts on individual behaviour and physiology through to community disruption. To date, however, there has been an almost exclusive focus on vertebrates. Not only does their central role in food webs and in fulfilling ecosystem services make imperative our understanding of how invertebrates are impacted by all aspects of environmental change, but also many of their inherent characteristics provide opportunities to overcome common issues with the current anthropogenic noise literature. Here, we begin by explaining why invertebrates are likely to be affected by anthropogenic noise, briefly reviewing their capacity for hearing and providing evidence that they are capable of evolutionary adaptation and behavioural plasticity in response to natural noise sources. We then discuss the importance of quantifying accurately and fully both auditory ability and noise content, emphasizing considerations of direct relevance to how invertebrates detect sounds. We showcase how studying invertebrates can help with the behavioural bias in the literature, the difficulties in drawing strong, ecologically valid conclusions and the need for studies on fitness impacts. Finally, we suggest avenues of future research using invertebrates that would advance our understanding of the impact of anthropogenic noise.

scholarly journals Evaluating anthropogenic noise impacts on animals in natural areas

2017 ◽  
Author(s):  
Alexander C. Keyel ◽  
Sarah E. Reed ◽  
Kathryn Nuessly ◽  
Elizeth Cinto-Mejia ◽  
Jesse R. Barber ◽  
...  
Keyword(s):  
Animal Species ◽  
Sound Propagation ◽  
Propagation Model ◽  
Anthropogenic Noise ◽  
Natural Areas ◽  
Noise Sources ◽  
Modeling Tools ◽  
Propagation Models ◽  
Model Predictions ◽  
Noise Impacts

SummaryNoise pollution is detrimental to a diversity of animal species and degrades natural areas, raising concern over the expanding footprint of anthropogenic noise on ecosystems. To guide management of noise sources, modeling tools have been developed to quantify noise levels across landscapes.We demonstrate how to model anthropogenic noise using sound propagation models, including noise from point, line, and polygon sources. In addition, we demonstrate three ways of evaluating spatially-explicit noise impacts, by identifying where noise 1) exceeds a sound level threshold, 2) is audible, or 3) has the potential to mask species communications. Finally, we examine approaches to mitigate these noise impacts on animal species.Noise sources in locations more favorable to sound propagation (e.g., locations with long, unobstructed lines-of-sight) will have a disproportionate impact on the surrounding area. We demonstrate how propagation models can identify sites with smaller acoustic footprints or sites that would benefit from additional noise-control measures.Modeling decisions, such as choice of sound propagation model, sound source information, and the quality of the input data, strongly influence the accuracy of model predictions. These decisions can be guided by comparing model predictions to empirical data when it is available.Synthesis and applications: Here, we demonstrate an approach for modeling and assessing anthropogenic noise sources across a landscape. Our versatile approach allows refining propagation outputs for species-specific questions as well as the quantitative evaluation of management alternatives. While the results are presented in the context of particular species, these approaches can be applied more generally to a wide range of taxa or used for multispecies assessments.

A temporal and spatial analysis of anthropogenic noise sources affecting SNMR

2014 ◽  
Vol 110 ◽  
pp. 34-42 ◽  
Author(s):  
E. Dalgaard ◽  
P. Christiansen ◽  
J.J. Larsen ◽  
E. Auken
Keyword(s):  
Spatial Analysis ◽  
Anthropogenic Noise ◽  
Noise Sources ◽  
Temporal And Spatial

External Recording Method for Estimating Hepatic Blood Flow With the Use of Radiogold

1959 ◽  
Vol 36 (1) ◽  
pp. 112-119 ◽  
Author(s):  
Joseph S. Burkle ◽  
Marvin L. Gliedman
Keyword(s):  
Blood Flow ◽  
Hepatic Blood Flow ◽  
Recording Method
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