Acoustic Remote Sensing as a Tool for Habitat Mapping in Alaska Waters
| Book title | Marine Habitat Mapping Technology for Alaska |
|---|---|
| Year | 2008 |
| Article DOI | 10.4027/mhmta.2008.03 (about DOIs) |
| Pages | 29–45 |
| PDF link* | View full text in PDF format [1 MB] |
*This low-resolution PDF is optimized for viewing on screen. High-resolution chapters are available on CD only.
Abstract
This presentation discusses the basics of acoustic remote sensing. The potential information content in measurements of backscatter depends on particulars of the system design. Important system parameters of side scan sonar include acoustic frequency, pulse length, beam width, and especially whether the measurements are qualitative or quantitative. For some acoustic remote sensing applications, the most important information is conveyed by the notable absence of backscatter because that may indicate the presence of an object lying on, or protruding out of, the seabed. In the context of mapping fishery habitats in Alaska and elsewhere, the notable absence of backscatter in measurements obtained via towed high-frequency side scan sonar is of limited usefulness. The operational deployment of towed side scan sonar, in particular whether it is towed close to the seabed or towed higher in the water column, can modify the potential utility of the backscatter measurements. The ability to infer information about the seascape in Alaska from the data provided by towed high-frequency side scan sonar is enhanced when the local slopes of the seabed are known. The presentation will discuss a variant of towed high-frequency side scan sonar which provides depth information that is derived as part of the acoustic remote sensing and how it can be applied to mapping benthic habitats in Alaska.
