Accession Number : AD0879650

Title :   Qualitative Observations of Scattering of 12 kHz Sound in the Eastern North Atlantic in July-August 1966 (MILOC 66).

Descriptive Note : Technical rept.,

Corporate Author : SACLANT ASW RESEARCH CENTRE LA SPEZIA (ITALY)

Personal Author(s) : Pedenovi, Clotilde

Report Date : 01 DEC 1970

Pagination or Media Count : 34

Abstract : Echo records were obtained using 12 kHz echo-sounders in the eastern North Atlantic during the MILOC 66 cruise of 6 July to 10 August 1966. Examination of the PDR records for depth, density, and distribution of the stratified scattering layers, showed that the DSL mostly consisted of three layers with wide geographic occurrence. The two shallower layers performed the characteristic ascent and descent at sunset and sunrise. The third layer only partially migrated, indicating that not all the scatterers participated in the evening ascent. Comment is made on the individual diurnal behaviour of the layers. The description given is intended to serve as a guide for quantitative studies of the relations between frequency and scattering strength of the DSL.

Descriptors :   (*UNDERWATER SOUND, ATLANTIC OCEAN), SCATTERING, VERY LOW FREQUENCY, ECHO RANGING, DEPTH FINDING, DENSITY, DISTRIBUTION, DIURNAL VARIATIONS, SHALLOW WATER, DEEP WATER.

Subject Categories : Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE