Accession Number:

AD0679627

Title:

ACOUSTIC ATTENUATION IN SEA ICE

Descriptive Note:

Interim technical rept.

Corporate Author:

MCGILL UNIV MONTREAL (QUEBEC) MACDONALD PHYSICS LAB

Personal Author(s):

• Langleben, M. P.
• Pounder, E. R.

Report Date:

1968-06-01

Pagination or Media Count:

21.0

Abstract:

A study is underway of the acoustic attenuation properties of sea ice. The transmitting transducer was driven by a sinusoidal signal whose frequency was swept mechanically over the frequency range 10 to 500 kHz. The suitably amplified signal from the receiving transducer was plotted against frequency on an X-Y recorder. No absolute power measurements were attempted, but the transmission path was reduced by stages and the resulting differences in received power compared. In a second series of laboratory experiments, small transducers were frozen at various positions through the ice sample to permit in situ power measurements. Results of laboratory and field measurements agree quite well on the pattern of attenuation with frequency, although the numerical values differ somewhat between different samples of ice.

Descriptors:

• *MECHANICAL WAVES
• *SEA ICE
• ACOUSTICS
• ARCTIC REGIONS
• ATTENUATION
• CANADA
• PROPAGATION
• RESONANT FREQUENCY
• SEA WATER
• SIMULATION
• TRANSDUCERS

Subject Categories:

• Snow, Ice and Permafrost
• Acoustics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE