Physical Oceanography Component Soundscapes Under Sea Ice: Can we listen for open water? LONG-TERM GOALS

The long-term goal of this collaborative research effort is to enhance the understanding of how variability in physical, biological, and acoustic signals impact marine mammal habitat use. This is especially critical in areas like the Bering Sea where global climate change can lead to rapid changes of the entire ecosystem. The Arctic is projected to experience ice-free summers within 30 years (Wang & Overland, 2009). This will have significant impacts for the natural ecosystem dynamics and human use associated with transportation, fishing, military activity, and energy exploration. Baseline measurements will play an important role in mitigation efforts and environmental assessments as military activity increases in the region. A major component of this research is to use passive ambient sound to identify the physical environment present, and then to use this information to interpret the biological data collected. OBJECTIVES The objectives of the passive acoustic component of this collaborative research effort are to identify and make synoptic measurements of the physical environment that the marine mammals (whales and seals) are using. Attention to the physical environment is often absent from biological studies and yet is an important component of biological processes. Physical oceanographic processes, including wave breaking, rainfall and sea ice processes, all have distinctive acoustic signatures that can be used to detect, classify and quantify them. Learning to identify physical processes acoustically will be an important aid to more encompassing ecosystem studies. Furthermore, ambient noise levels in the Bering Sea are measured directly and provide a background baseline for future studies and operations. Long-term measurements will play an important role in determining the point at which cumulative effects of the environment and human activities impact animal populations, and in identifying the kinds o