Experimental Assessment of Underwater Acoustic Source Levels of Different Ship Types

The contribution of shipping noise to the background noise in the seas can be estimated by shipping noise maps. Noise maps can be made by applying appropriate modeling tools for underwater sound propagation and ship source levels to information on the acoustic environment and on the ship traffic in the area of the map. The development of reliable source level models requires the availability of a variety of radiated noise data of ships. Therefore, full-scale radiated noise measurements were performed near a shipping lane in coastal waters out of the Port of Rotterdam. The results of the noise measurements are combined with information about the measured ships and their positions, derived from registered AIS data, and with propagation conditions to determine source levels. Criteria have been developed to select the data from which a reliable source level estimation can be obtained from individual ship passages at the busy shipping lanes. Source levels of different types of ships are compared.