Assessing the Underwater Ship Noise Levels in the North Tyrrhenian Sea

The purpose of this research was to assess the anthropic underwater noise caused by ships within the Cetacean Sanctuary, a wide area in the North Tyrrhenian Sea. Noise from low-frequency continuous sounds has been investigated within the 1/3-octave bands centered at 63 and 125 Hz. All the information about noise sources and sound attenuation have been organized in a database; a tool automatically extracts useful information from it and feeds a ray-tracing model to estimate noise levels. The results show average levels generally over the 100 dB re 1 mu Pa value.