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Underwater noise levels in UK waters
Nathan D Merchant1, Kate L Brookes2, Rebecca C Faulkner1
1Centre for Environment, Fisheries &Aquaculture Science (Cefas), Lowestoft, UK.
Scientific Reports
|November 11, 2016
Summary
Rising underwater noise threatens marine ecosystems. This study highlights the need for percentile-based noise indicators and decades of monitoring for robust environmental policy.
Area of Science:
- Marine acoustics
- Environmental monitoring
- Ecosystem health
Background:
- Human activities are increasing underwater noise pollution.
- This noise impacts marine life and ecosystems.
- Current data on underwater noise levels is insufficient for effective policymaking.
Purpose of the Study:
- To quantify underwater noise levels across the UK.
- To support policy objectives under the EU Marine Strategy Framework Directive (MSFD).
- To evaluate statistical methods for environmental noise indicators.
Main Methods:
- Field measurements conducted at twelve UK sites (2013-2014).
- Analysis of noise levels in one-third octave bands (63-500 Hz).
- Comparison of Root Mean Square (RMS) levels with percentile metrics.
Main Results:
- Median noise levels ranged from 81.5-95.5 dB re 1 μPa.
- Significant variation in anthropogenic noise, with persistent vessel noise in North Sea sites.
- RMS levels were skewed by outliers, unlike percentile metrics.
Conclusions:
- Environmental indicators for anthropogenic noise should utilize percentiles for statistical robustness.
- Continuous monitoring for at least three decades is necessary to detect meaningful trends.
- The study provides crucial data for UK marine policy and noise pollution management.
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