A yearlong record of ambient sound on the Chukchi Shelf

Abstract

Studies of ambient sound in the Arctic, both under ice and in the marginal ice zone, have spanned more than 50 years, but rapidly changing conditions with regards to declining ice cover have reduced the relevance of measurements taken in previous decades. Changes in the environment have resulted in changes in the ambient sound field, affecting both the sound generating mechanisms and the sound propagation. From October 2016 to October 2017, the Shallow Water Canada Basin Acoustic Propagation Experiment (SW CANAPE) was conducted on the Chukchi Shelf. One goal of CANAPE was to observe the changing soundscape. This talk presents acoustic recordings collected on the 150-m isobath with the Persistent Acoustic Observation System (PECOS), which contained a horizontal line array of hydrophones along the seabed and a vertical line array spanning a portion of the water column. This study examines the ambient sound level and uses k-means clustering to quantify the occurrence of six unique spectral shapes associated with different seasons and various sound generation mechanisms. The spectral clusters are correlated with environmental observations including sea concentration and thickness, wind speed, and air temperature. [Work supported by ONR.]