Baltic Marine Environment
Protection Commission

Underwater Noise

General Information

This program relates to the contribution of anthropogenic sounds in the underwater environment. The main sound sources are either continuous such as commercial ships, recreational boats and offshore wind farms or impulsive such as impact piled driving, seismic explorations or underwater explotions. Sound travel over large distances underwater and crosses national borders.

 Sub-programme: Ambient noise

The Life+ project Baltic Sea Information on the Acoustic Soundscape (BIAS project) produced soundscape maps in 2016, showing the underwater noise generated by commercial vessels, the major source of human-induced underwater noise in the Baltic Sea. Seasonal soundscape maps were produced for the demersal, pelagic and surface zones. These soundscape maps will serve as a baseline for the development of monitoring and assessment of ambient noise in the Baltic Sea.

The regional monitoring sub-programme of continuous noise based on the output from the BIAS project was aproved by HOD 54-2018 (Appendix 1 to document 4-19). The sub-programme is composed by a combination of two alternative monitoring programmes based on yearly minor assessment in a few prioritized locations and major assessment every e.g. 6 years. 

Sub-programme: Registry of impulsive sounds

NOTE: This sub-programme is still under development.

There is currently a regionally organized registry of impulsive events in the Baltic Sea region. The registry is hosted by ICES and the development of the registry follows the same approach as for the OSPAR region. Such registry makes an account of the number of days with selected activities that create impulsive sounds that can be harmful for marine animals and make it possible to evaluate cumulative impacts of noise.

The registry of impulsive events requires information on e.g. position data of the activity, licensing block/area, date of operation, source operation, sound mitigation system. The registry is implemented as a GIS-based tool where sound levels of events (or proxies for sound level, such as air gun array size and hydraulic hammer energy) are stored and a map visualisation is enabled.

Responsible HELCOM Subsidiary Bodies


State & Conservation

Contact information:   HELCOM Secretariat