A study of range dependent acoustical field based on the FVCOM model: A Case of typhoon NANMADOL

Abstract

This study simulated the acoustical field in the western North Pacific (WNP) during typhoon NANMADOL, based on the FVCOM model and Range dependent Acoustic Model RAM. We implements a new approach, which helps to accurately characterize the energy distribution of acoustical field obtained by considering the range dependent ocean dynamical environment elements. The results show that, the sound speed profile in the upper-layer ocean of the sea water decreases to a certain extent on the day after the typhoon’s arrival, while the maximum decrease in the sound speed after the typhoon’s transit occurs 1∼2 days. The maximum decrease in the seawater sound speed can be up to 2-3 m/s 2 days after the typhoon’s transit. The passage of the typhoon mainly affects the far-field acoustical energy distribution when the sound source is located near the upper-layer ocean.