In the first evaluation of this descriptor for the subdivision of the Azores, it was described that the existing information on marine noise was very limited, whether at the level of environmental noise monitoring, or at the level of the recording of anthropogenic activities producing impulse noise. This lack of information made it impossible to assess the Good Environmental State for this descriptor. Until such reporting, despite the existence of some programmes and projects using autonomous submarines, in regions surrounding the Exclusive Economic Zone (EEZ) of the Azores, which could characterise marine noise around the region, the information gathered was not analysed in this sense. In this way noise has been indirectly characterised by the identification of its sources, endogenous or exogenous. The Azores archipelago is a major migratory habitat and area of food for a variety of whale species, such as blue whale (Balaenoptera musculus), Balaenoptera physalus (Balaenoptera physalus) and sardinella borer (Balaenoptera borealis), which are directed to the waters of northern Atlantic. It is therefore of great interest that projects enabling the monitoring of underwater noise be developed so as to ensure that effective government measures are taken to guide human activities in these Azorean waters. In this context of the MSFD it is still not possible to assess good environmental status, considering the lack of available data and thresholds, established at European Union level, for impulse noise levels (D11C1).

In the first evaluation of this descriptor for the subdivision of the Azores, it was described that the existing information on marine noise was very limited, whether at the level of environmental noise monitoring, or at the level of the recording of anthropogenic activities producing impulse noise. This lack of information made it impossible to assess GES for this descriptor. Until such reporting, despite the existence of some programmes and projects using autonomous submarines, in regions surrounding the Exclusive Economic Zone (EEZ) of the Azores, which could characterise marine noise around the region, the information gathered was not analysed in this sense. In this way noise has been indirectly characterised by the identification of its sources, endogenous or exogenous. The Azores archipelago is a major migratory habitat and area of food for a variety of whale species, such as blue whale (Balaenoptera musculus), Balaenoptera physalus (Balaenoptera physalus) and sardinella borer (Balaenoptera borealis), which are directed to the waters of northern Atlantic. It is therefore of great interest that projects enabling the monitoring of underwater noise be developed so as to ensure that effective government measures are taken to guide human activities in these Azorean waters. In this context of the MSFD it is still not possible to assess good environmental status, considering the lack of available data and thresholds established at European Union level for low frequency continuous noise levels (D11C2).