Acoustic propagation and ambient noise in a thawing Arctic

Abstract

Over the past 50 years, the extent and volume of sea ice coverage in the Atlantic Ocean has been receding at a nearly linear rate due to anthropogenic induced climate change. It is expected that some time within the next 10 to 30 years, there will be an ice free summer. For periods beyond this time, the Arctic Ocean will change from mostly covered by multi-year ice to mostly covered by first year ice. In this talk, the impact of the changes in ice morphology (roughness and thickness) and ice extent will be examined from both an under-ice propagation modeling and an ambient noise modeling perspective. The first year ice is expected to have less loss, leading to better sound propagation. The reduced ice coverage will lead to more open water exposed surfaces for wind generated noise, and more open water for ice-free propagaiton of shipping induced anthropogenic sound. Both of these features will drive up the background level of sound in the Arctic Ocean. Regional differences in ice cover and expected wind and shipping noise will be addressed.