Measurements of open-water arctic ocean noise directionality and transport velocity

Measurements from bottom-mounted acoustic vector sensors, deployed seasonally between 2008 and 2014 on the shallow Beaufort Sea shelf along Alaskan North Slope, are used to estimate ambient sound pressure power spectral density, transport velocity of energy, dominant azimuth 25 450 Hz. Even during ice-free conditions, this region has unusual features when compared against other U.S. coastal regions. Two distinct regimes exist in diffuse noise environment: one with high density levels but low directionality, another lower directionality. The transition two states, which is invisible traditional spectrograms, occurs 73 79 dB re 1 ?Pa2/Hz at 100 Hz, occurring higher frequencies. Across a wide bandwidth, high-directionality consistently arrives geographical azimuths 0° 30° true north over multiple years locations, seasonal interquartile range 40° frequencies velocities. long-term stability directional regime, believed arise dominance wind-driven sources an east–west coastline, makes it important feature arctic sound.