Underwater noise and other forms of energy
1. Identify and review existing data and monitoring methods on underwater noise
The work should be based on a review of experiences within MS for different sources and the knowledge within the scientific community in this field. It should be related to the two identified indicators in the Commission decision:
• Proportion of days and their distribution within a calendar year over areas of a determined surface, as well as their spatial distribution, in which anthropogenic sound sources exceed levels that are likely to entail significant impact on marine animals measured as Sound Exposure Level (in dB re 1 (aPa2 s) or as peak sound pressure level (in dB re 1 nPapeak) at one metre, measured over the frequency band 10 Hz to 10 kHz (11.1.1)
• Trends in the ambient noise level within the 1/3 octave bands 63 and 125 Hz (centre frequency) (re lpPa RMS; average noise level in these octave bands over a year) measured by observation stations and/or with the use of models if appropriate (11.2.1).
2. Develop proposals for methodological standards to monitor loud impulsive sounds
The proposed methodological standard must be feasible and implemented with reasonable efforts. It should describe what type of instruments to be used for which frequencies, how to monitor Source Level and Exposure Level, sampling method, filtering, statistical analysis methods, etc. The proposal should take into account differences in physical features in the European seas with respect to configuration, depth, morphology.
3. Develop proposals to monitor low frequency continuous sounds
The proposed monitoring must be feasible and implemented with reasonable efforts. It should describe what type of instruments to be used for which frequencies, how to monitor Source Level and Exposure Level, sampling method, filtering, statistical analysis methods, etc. But also other methods including the use of models to develop ‘ sound maps’ need to be considered. The proposal should take into account differences in physical features in the European seas with respect to configuration, depth, morphology.
4. Assess the need to develop indicators for other forms of energy
Underwater noise has been highlighted though out the Directive and also in the Decision on criteria and methodological standards on GES. But also the other forms of energy such as thermal energy, electromagnetic fields and light need to be assessed. Questions need to be answered such as: What are the potential impacts? How to monitor the pressure? Is there a need to develop this into a GES indicator? What are appropriate indicators?
5. Objectives and targets
The technical subgroup provides a common platform for addressing how to develop objectives (characteristics of GES), environmental targets and associated indicators in relation to underwater noise and other forms of energy. This common reflection can then be taken further within each marine region and subregion (in close cooperation with the regional sea conventions) and at national level.
6. Research needs
Additional scientific and technical progress is still required to support the further development of criteria related to this descriptor, especially in relation to the impacts of relevant noise and frequency levels on marine life. A close collaboration at the science -policy interface should ensure that research items of special importance for the MSFD implementation are being recognised.
Interim reports will be required prior to the meetings of the WG on GES. These brief reports should indicate the status of the subgroup work. The final report by itself can be short. It should explicitly address the issues identified in the ToR. The substance of the work will be in annexes; these can be much more detailed.
Source: dredging, October 6, 2010