Short-term variability in nighttime scattering strength levels at one site in the eastern Algero-Provençal Basin

Abstract

A sequence of nine nighttime, broadband volume scattering strength measurements obtained in 1973 over a period of approximately one hour was used to study the short-term variability of scattering strength in 100 Hz bands over frequencies ranging from 100 Hz to 24 kHz and depths ranging from 400 meters to 1000 meters. The variability was found to be independent of depth and was least in the frequency range three kHz to eight kHz where the standard deviation was approximately four dB less than the mean level, Outside this frequency range the standard deviation was somewhat greater than the mean level.