Acoustics in global process ocean observatories
Date of Original Version
Long-term ocean observatories use mainly three acoustic measurement technologies including long-range positioning and navigation, thermometry/tomography, and passive listening for collecting data for climate, geological, and biogeochemical studies. The long-range systems include sound fixing and ranging system (SOFAR) that uses linear frequency modulated sweep signals of 260 hertz with a 1.5-hertz bandwidth. Ocean acoustic tomography uses higher bandwidth signals to measure travel times over several crossing acoustic paths, which can be further used to infer ocean temperature. Similar data can be used to infer ocean heat content along individual acoustic paths under thermometry. Passive acoustic listening having paramount signal recognition, has been applied to several branches of marine science and signal processing techniques have been developed to study sounds generated by physical processes. This method is used in sensing marine mammals, identification of fishes, detection of seismic waves and climate, and measurement of noise generated by human activities in the ocean.
Duda, Timothy F., Bruce M. Howe, and James H. Miller. "Acoustics in global process ocean observatories." Sea Technology 48, 2 (2007): 35-38. https://digitalcommons.uri.edu/oce_facpubs/364