This is not a particular project or programme, but a reminder of the existence of acoustic observatories ("polygons") within the Ministry of Defence which are capable of fulfilling MSFD monitoring needs. For military needs, the Ministry of Defence uses its permanent equipped sites for its activities and experiments. Measurements of interest to MSFD (monitoring impulse broadcast and acquisition of long time series of traffic noise) could be conducted, at least in part, on these sites. These measurements, when made available, could be compiled and used for monitoring environmental status.

Continuous sound is one of the criteria for defining good ecological status for descriptor 11 relating to the pressure of noise generated by human activities in the context of the MSFD (D11C2). Good ecological status for sound energy is achieved when the risks of acoustic disturbance, excess mortality from sound exposure and reduction in communication distances of mysticetes are cumulatively low or moderate. For this, the spatial distribution, the temporal extent and the acoustic levels of continuous anthropogenic sounds must not exceed levels harmful to populations of marine animals. These criteria are assessed at the scale of the marine sub-region for the "Channel and North Sea", "Celtic Seas" and "Western Mediterranean" regions; and at the scale of the "North" and "South" subdivisions in the "Bay of Biscay" sub-region. One of the indicators selected for the evaluation of criterion D11C2 is the spatial distribution of annual ambient noise for the one-third octave band centered on 125 Hz (D11C2.2). The pressure considered for the evaluation of the criterion is the noise generated by maritime traffic, mainly in its trade and transport component which is subject to regulatory oversight by automatic identification system (AIS). The data used for the calculation of this indicator are in situ noise data (MAMBO device) and maritime traffic data (Lloyd’s).

Impulsive or transient sounds of short duration and of high intensity constitute one of the criteria for defining good ecological status for descriptor 11 relating to the pressure of noise generated by human activities within the framework of the MSFD (D11C1). Good ecological status for sound energy is achieved when the risks of acoustic disturbance, excess mortality from sound exposure and reduction in communication distances of mysticetes are cumulatively low or moderate. For this, the spatial distribution, the temporal extent and the acoustic levels of the sources of anthropogenic impulsive sound must not exceed the levels harmful to the populations of marine animals. These criteria are evaluated at the scale of the marine sub-region for the “English Channel and North Sea”, “Celtic Seas” and “Western Mediterranean” regions; and at the scale of the "North" and "South" subdivisions in the "Bay of Biscay" sub-region. One of the indicators selected for the evaluation of criterion D11C1 is the spatial distribution of impulse emissions (D11C1.2). The pressures considered for the evaluation of the criterion are: acoustic emissions from air guns; acoustic emissions from impulsive sources other than air guns; emissions from non-impulsive (transient) sources; underwater explosions; emissions due to pile driving. The data used for the calculation of this indicator are declarative emissions data traced by the operators of the activities generating impulsive noise.