Effect of underwater sound channel on variation of ambient noise level in eastern sea of Korea

Abstract

In this study, we investigated the effect of the underwater sound channel (USC) on variations in the ambient noise level in the eastern sea of Korea. Hydrophone observations near the USC axis indicated that the ambient noise levels for frequencies <200 Hz were considerably higher than those at other hydrophone depth locations. However, for frequencies >200 Hz, only slight variations in the ambient noise level were detected, regardless of hydrophone depth or distance relative to the USC. The results from this study shows a typical example of the low-frequency ambient noise (<200 Hz) in shallow water being effectively propagated a long distance near the USC axis in the deep ocean along continental slope. (C) 2014 The Japan Society of Applied Physics