Analysis of underwater acoustic data collected under sea ice during the Useful Arctic Knowledge 2021 cruise

• Main Authors: Jenkins, William, Johnson, Hayden, Vakhutinsky, Sofia, Helmberger, Meghan Nicole, Storheim, Espen, Sagen, Hanne, Sandven, Stein
• Format: Conference Proceeding
• Language: English
• ISSN: 1939-800X
• DOI: 10.1121/2.0001574

Acoustical observations are presented from the Useful Arctic Knowledge (UAK) 2021 cruise, an early-career training program which took place in sea ice north of Fram Strait in June 2021 on board the Norwegian Coast Guard icebreaker KV Svalbard. Through oceanographic sampling and three acoustics-related tasks, participants were introduced to practical applications of underwater acoustics and observed the ocean environment and its role in acoustic propagation. Propagation modeling from oceanographic sampling confirmed an upward-refracting environment throughout the cruise. In the first task, a drifting acoustic receiver buoy with a single hydrophone was deployed in an ice floe and left to passively record for eight days. Various biological sounds were recorded, including bearded seals and cetaceans. In the second task, acoustic localization using an active pinger system was used to recover an operational oceanographic mooring from the seabed. The third task involved passive acoustic observations beneath sea ice whenever KV Svalbard fastened herself to ice floes and measurements of the ice were made. Through the UAK 2021 cruise, participants learned the utility and value of using underwater acoustics for operations in the Arctic Ocean, particularly in location and retrieval of equipment and in measuring and sensing the environment.