Toward predicting Arctic Ocean acoustic travel times using an Earth system model

Abstract

The hydroacoustic environment of a rapidly warming Arctic Ocean will be impacted by changing thermohaline structure, increased marine traffic, changes in sea ice coverage, and likely increases in microseism/storm noise. This will lead to obsolescence for today’s Arctic Ocean acoustic models just as the need for understanding and monitoring the Arctic acoustic environment becomes more critical. To make sophisticated predictions for coming conditions, we need fully-coupled Earth system models. Los Alamos National Laboratory is contributing to developing the Department of Energy’s Energy Exascale Earth System Model (E3SM), which can potentially predict the ocean and sea ice conditions necessary to drive an acoustics model in a rapidly-evolving Arctic Ocean. We present a preliminary analysis of a comparison of acoustic travel times in the Canada Basin calculated from E3SM simulations with measured travel times from the 2016–2017 Canada Basin Acoustic Propagation Experiment (CANAPE) and travel times computed from ice-tethered-profiler measurements of acoustic properties in the water column. The goals of this effort are to provide boundary ocean conditions to an acoustic model, to quantify the ocean acoustic implications of climate change, as well as to create a climate-aware atlas of global acoustic noise that could be applied, for example, in signal detection.