Automated ship noise measurement system and Enhancing Cetacean Habitat and Observation program ship noise database

An automated ship Underwater Radiated Noise (URN) system has been developed and applied to process measurements of tens of thousands of commercial vessel transits, to produce the Enhancing Cetacean Habitat and Observation (ECHO) Program’s Ship URN database—believed now to be the largest existing ship URN database. The system integrates environmental data (ocean current, wind speed), vessel AIS broadcasts, vessel classification metadata obtained from commercial ship databases, and acoustic data from JASCO’s Underwater Listening Stations (ULS). It utilizes advanced signal processing methods (e.g., image symmetry detection, cepstrum, harmonic analysis, DEMON) to automatize analysis tasks such as estimating vessel closest point of approach and propeller rotation rates. Full wave models are applied to calculate propagation loss. Vessel noise emissions (Radiated Noise Level and Source Level) are determined in compliance with ANSI standard 12.64-2009 Grade C protocols, correcting for background noise in all frequency bands. Additionally, ShipSound offers a comparative ranking system for vessel noise emissions relative to peers of the same category. All data and metadata are stored in a database and are accessible through a full-featured web interface. In this paper, we will describe the processing system details and provide examples of measurement reports and metadata displays.