Coordinated Arctic Acoustic Thermometry Experiment Planning and Long-range Preparation
Abstract
Scripps Institution of Oceanography (Co-PIs: Matthew Dzieciuch and Peter Worcester) proposes to develop plans and make long-range preparations for the Coordinated Arctic Acoustic Thermometry Experiment (CAATEX), a joint U.S.-Norwegian acoustic propagation experiment across the Arctic basin. Our Norwegian partner is the Nansen Environmental and Remote Sensing Center (NERSC) in Bergen, led by Hanne Sagen. The CAATEX experiment would take advantage of the EU project MOSAiC, in which an icebreaker, the R/V Polarstern, will drift across the Eastern Arctic in the Transpolar Drift from summer 2019 to summer 2020. Transmissions from an acoustic source deployed from the icebreaker will enable remote sensing of the Arctic basin. The NERSC proposal for the source deployment and two receivers has been funded by the Norwegian Research Council, contingent on funding from an American partner. We anticipate proposing to deploy at least two receivers in the western Arctic. The planning and preparations include the testing of a potential acoustic source and travel to develop the scientific and engineering plans. This proposed experiment is designed to be comparable to previous trans-Arctic propagation experiments conducted in the 1990s. The drift track and multiple receivers of CAATEX will allow for an expansion of the measurements throughout the basin. The comparisons will contrast present day heat content to the past measurements, but there are several other points of comparison. These include transmission loss, which depends in part on the ratio of first-year ice to older ice; acoustic scattering, which diagnoses the strength of internal-wave activity; and the acoustic arrival structure, which changes with the vertical stratification. More capable receiving arrays and a more compact sound source that can be deployed from a ship will be able to extend the analysis beyond previous work. Support for testing the source and for laboratory personnel to upgrade and modernize acoustic receivers is a necessary part of the preparation. The hardware costs have already been provided for through two FY17 DURIPS: (1) “Second-generation Controllers for Distributed Vertical Line Array (DVLA) Underwater Acoustic Receivers” (N00014-17-1-3010) and (2) “Low-frequency Acoustic Sources for Ocean Acoustic Propagation Experiments” (N000014-17-1-3006). Our goal is to explore the fundamental limits of acoustic signal processing and to exploit the remote sensing capabilities of acoustics to characterize the large-scale properties of the Arctic ocean.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 26, 2018
- Source ID
- N000141812149
Entities
People
- Matthew A. Dzieciuch
Organizations
- Office of Naval Research
- United States Navy
- University of California, San Diego