Validation of estimated underwater radiated noise propagation from a ship using the parabolic equation method by underwater sound measurements in actual sea

Abstract

In 2022, the International Maritime Organization started a review of the nonmandatory guidelines for the reduction of underwater radiated noise (URN) from ships and a discussion about the next step. In the case of considering the extent of underwater radiated noise from a ship, the propagation of the URN and the background noise in the sea area should be considered in addition to the source level of the URN. In this study, the time series of the received levels of underwater sound measured off Izu-Oshima Island, Japan, are shown in the 1/3 octave band level. The time series of the received levels were compared with the propagation loss estimated by the parabolic equation method to validate the accuracy of the estimation of the propagation of underwater sound in the measurement area.