Measurements with an Automatically Recording Inverted Echo Sounder; ARIES and the Bubble Clouds

Abstract

Inst. Oceanogr. Sci., Wormley, Godalming, Surrey, GU8 5UB, UK J (Journal-Article) M (Marine) The author reports analysis of the first observations with a new instrument, ARIES, designed to record the acoustic backscatter from bubble clouds at several levels below the surface of the ocean. The instrument is deployed on a subsurface mooring and records internally. Data has been analysed from deployments of ARIES for one week in the Irish Sea and for periods of 4 and 9 weeks near the edge of the UK continental shelf, during periods in which meteorological data, waves, and near-surface temperatures and, on occasion, currents, were being recorded by other instruments. The results, while being generally similar to earlier measurements in coastal waters, show that the bubble clouds are more intense, having greater acoustic scattering cross sections per unit volume, M sub( upsilon ), and extend, on average, deeper into the water column Ocean...