The research on ambient noise of Arabian Sea

Abstract

The Arabian Sea is an important shipping channel. The frequency and spatial variation characteristics of medium and low frequency ambient noise in this area are studied by analyzing underwater acoustic buoy data. In this area, the shipping noise is the major noise source. The mean noise spectrum of each month is asymmetric "W" type among 10 ∼ 1000 Hz. Noise level decreases gradually from 10 Hz to 15.9 Hz, and increases from 20 Hz to 40 Hz. The spectral peak occurs among 40 ∼ 63.5 Hz. Noise level decreases from 63.5 Hz to 127 Hz, and varies little between 127 Hz and 1000 Hz. In the depth range of 75 ∼ 450 m, the vertical variation of 50.4 Hz noise is the largest. The noise grows substantially in the range of 75 ∼ 250 m, and changes less in the range of 250 ∼ 450 m.