Characterization of arctic ambient noise environment

Abstract

Historically, ambient noise in arctic ocean is predominately produced by diffuse thermal ice cracking events or ice ridge grinding. Isotropic, range-distributed noise sources models are typically utilized to simulate this environment. However, the presence of the Beaufort Lens and changes in the arctic climate have altered its ambient noise environment. Specifically, the new noise environment consists mostly of ice cracking events which occur at discrete ranges and bearings. As a result, these noise models may no longer be adequate. This study analyzes ambient noise data collected in the Beaufort Sea during the 2016 ICEX US Navy Exercise to characterize the new arctic ambient noise environment. Points of focus include determining whether ice cracking noises in the new environment are discrete in time or continuous as is the result from analysis of the SIMI’94 arctic ambient noise data. Statistics on the ice cracking events in the new noise environment, such as the events’ amplitude distribution, are also presented with the motivation of better describing the environment so that more precise models may be created.

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