IVL researchers develop new method to map recreational boat noise

Researchers at the IVL Swedish Environmental Research Institute have developed a new method to map underwater noise generated by recreational boats. Because these vessels lack Automatic Identification System (AIS) transmitters, they have historically been difficult to include in noise maps.

By combining satellite imagery, acoustic measurements, and sound propagation models, the researchers successfully created geographic noise maps in the Kosterhavet area. The study indicates that noise from recreational boats in this region significantly exceeds natural background levels.

The findings suggest that implementing speed limits may be a more effective way to mitigate noise in sensitive coastal areas than attempting to limit the total number of boats. For example, adhering to a five-knot speed limit could provide a noticeable reduction in noise that outweighs the impact of an increased number of vessels. This new method, which utilizes freely available satellite data, can be applied to other coastal regions to assist in environmental assessments and the protection of marine ecosystems.