To truly comprehend winter Arctic waters in the manner that has been achieved in world’s more temperate oceans, autonomous underwater platforms (e.g., floats, gliders) require additional capability for underwater geolocation and periodic communication. Underwater geolocation and data communication remain the largest obstacles to exploiting the promise of year-round 3-D sampling of Arctic waters available from floats and gliders. Modern underwater acoustic positioning systems also enable ocean acoustic tomography (measurement of basin scale temperature and currents) and passive acoustic listening (marine mammals, ambient noise from ships, sonar, ocean-based resource exploitation and ice dynamics).
We will produce a feasibility study of a Baffin Bay Acoustic Navigation and Communication (BBANC) system. The size of a Baffin Bay system rests between the basin scale, low frequency (~3000 km, 40-100 Hz) and regional scale, intermediate frequency (50 – 300 km, 250-1500 Hz). This feasibility study will make recommendations regarding acoustic source frequency, bandwidth, locations, mooring type, sensor complement, system power requirements, technology to shutdown the system during periods of marine mammal migration, environmental and community impacts, etc. Additional field measurements required for full system specification and additional research and development activity required to implement a design will be identified. Peer review by interested collaborators will be facilitated through workshops, status reports and regular communication.
Over the last few decades, numerous successful deployments of under-ice positioning systems have been carried out using underwater acoustic positioning systems for oceanographic research1,2 and sea floor mapping3. The scale of these systems is relatively small. For example, the Davis Strait system implemented by University of Washington Applied Physics Laboratory (UW APL) covers the area of Davis Strait, approximately 75 x 250 km. Baffin Bay, at approximately 1400 x 550 km4, represents a larger challenge. See Fig. 1. We have chosen to bring together international experts who have previously been involved with designing, planning, implementing and using such high-latitude acoustic navigation and communication systems along with Canadian acoustic experts from academia, defence and industry to carry out this project.