Observations of high-frequency acoustic volume backscattering in the mid-Yellow Sea

Observations of high-frequency acoustic volume backscattering in the mid-Yellow Sea were made in the summer of 1996 by a 200kHz fish finder.The received scattering signals were recorded by a tape recorder and then processed by a computer. It was found that the backscattering was strong at night and became much weak in the daytime. The echo images showing the depth-dependent backscattering as a function of time, the downward movement of scatters near dawn and internal waves are presented.