Interannual changes in sound propagation across the Gulf Streama)
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View abstract on PubMed
Summary
This summary is machine-generated.Ocean warming alters sound travel times and interference patterns across the Gulf Stream. This study used satellite data and Argo floats to analyze changes in sound propagation due to the changing ocean environment over 14 years.
Area Of Science
- Oceanography
- Acoustics
- Climate Science
Background
- The Gulf Stream's changing ocean environment impacts underwater sound propagation.
- Understanding these changes is crucial for acoustic monitoring and research.
Purpose Of The Study
- To investigate the effects of a changing ocean environment on sound propagation across the Gulf Stream.
- To quantify changes in sound travel time and interference patterns over a 14-year period.
Main Methods
- Utilized satellite altimetry and Argo float hydrographic profiles.
- Reconstructed Gulf Stream vertical structure using the altimetry-informed gravest empirical mode (AGEM) method.
- Employed ray tracing and parabolic equation sound propagation models.
Main Results
- Observed a reduction in sound travel time to 120 km due to increased water temperatures.
- Identified changes in the sound speed gradient field structure.
- Found altered sound propagation interference patterns on the far side of the Gulf Stream.
Conclusions
- Ocean warming significantly affects underwater sound propagation across the Gulf Stream.
- Changes in sound speed fields alter acoustic propagation patterns over decadal timescales.
- The AGEM method provides a robust way to estimate 3D sound speed fields from surface altimetry.
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