Accession Number : ADA325452

Title :   Development of a Low Frequency Ambient Noise Storm Model for the Arctic Ocean.

Descriptive Note : Master's thesis,

Corporate Author : NAVAL POSTGRADUATE SCHOOL MONTEREY CA

Personal Author(s) : Collins, David A.

PDF Url : ADA325452

Report Date : DEC 1996

Pagination or Media Count : 155

Abstract : The development of an ambient noise model for use in ice-covered Arctic waters is the primary goal of this research. The generation of ambient noise is considered to originate from large scale deformation of the ice cover (pressure ridge formation) which is caused on a synoptic scale by convergence of the ice cover due to wind stress/speed associated with the passage of Arctic storms. The Arctic Storm Noise Model (ASNM) has been developed as a dynamic model to predict the occurrence of extreme noise events. The emphasis is on accurately predicting the large increases or decreases in ambient noise, which observations have shown to be in the order of 20 to 30 dB over a matter of hours. ASNM was adapted from the Ambient Noise Directional Estimation System (ANDES) for use under the Arctic pack ice. ASNM predictions are compared quantitatively to noise measurements made by ice-mounted drifting buoys in the Arctic basin during the early 1990's. Results showed that for extreme events (<5th or >95th percentile) ASNM is accurate in predicting both the level of ambient noise and the large increases in the noise record. Due to the encouraging results further improvements are recommended to increase the robustness of the model for potential tactical use by submarine units operating under the Arctic pack ice.

Descriptors :   *AMBIENT NOISE, *ARCTIC OCEAN, DATA BASES, MATHEMATICAL MODELS, OCEAN SURFACE, DEFORMATION, THESES, ICE MECHANICS, ICE FORMATION, STORMS, ACOUSTIC MEASUREMENT, WIND VELOCITY, UNDERWATER ACOUSTICS, ACOUSTIC DATA, LOW FREQUENCY, WIND STRESS, OCEAN BASINS, SEA ICE, PACK ICE.

Subject Categories : Physical and Dynamic Oceanography
      Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE