A Review of the Acoustic Propagation Characteristics Near the SAS Site Using Archival CTD Profiles.
Abstract
The Synthetic Aperture Sonar component of the Coastal Mixing and Optics Experiment is planned for August of 1996, south of Woods Hole at 40.5 deg N, 70.5 deg W. Water depth is about 70 m. Thirty archival CTD casts from the months of July and August have been used to study the likely acoustic propagation conditions near the site. The archival casts show two-layer stratification with high speed surface water and deeper slower water separated by a high-gradient region. For a transmitter 10 m above the bottom, nearly horizontal rays occur at ranges near the transmitter. As range increases, at least two caustics are passed. Between the caustics, two ray paths that traverse the high-gradient depth region are present along with the near-horizontal path. Both the near-horizontal and the paths that sample the high-gradient region are of interest. Casts near the proposed site from depths of 60-80 m, indicate conditions favorable for measuring both types of paths. At deeper sites, the propagation region between the caustics moves beyond our maximum range of 1000 m. At shallower sites, separating arrivals will be difficult because the ray pattern is shortened in range.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1995
- Accession Number
- ADA293294
Entities
People
- Frank Henyey
- Kevin L. Williams
- Steve Reynolds
- Terry Ewart
Organizations
- University of Washington