APL-UW Next Generation Oceanic Noiseology
Abstract
Multiple efforts involved measurement and characterization of oceanic ambient noise. Data from the Comprehensive Test Ban Treaty Organization hydroacoustic station HA11N1, Wake Island, showed a decreasing trend in noise levels around 40 Hz from 2008, but a recent change to an increasing trend. The decreasing trend corroborates previous reports using data collected elsewhere in the N. Pacific. Additionally, HA11N1 monthly measurements in early 2020 showed a slight decrease of about 1 dB from the year before, possibly due to the global economic slowdown caused by the SARS-Cov-2 pandemic, but this effect disappeared by August 2020. Measurements made from a SeaGlider showed that observed ocean noise from about 100 to 300 Hz was biased when the vehicle was moving relative to the water, ostensibly from flow noise. Incomplete and incorrect system calibrations for low-frequency hydrophone channels in the Ocean Observatories Initiatives Regional Cable Array were identified and corrected. Fieldwork off Kauai in 2019 demonstrated that the HX554 electroacoustic transducer remains viable.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 11, 2021
- Accession Number
- AD1136173
Entities
People
- Rex K. Andrew
Organizations
- University of Washington