Optical Detection of Ensonified Ocean Waves
Abstract
Over 80% of global ocean basins bathymetry are currently indirectly estimated using satellite measurements of marine gravity anomalies infer bathymetry. Where available, ship-based soundings can help constrain satellite-based techniques, and result in potentially more accurate bathymetric products. Their use, however, requires the presence of a sound source aboard a vessel, which can presentlogistical challenges. Sound sources of opportunity such as commercial vessels can help alleviate these logistical challenges, but their use is limited to well-established shipping channels. This proposal explores the possibility of using airborne sources of sound to infer bathymetry. If found feasible, the technique can greatly alleviate the time taken to conduct bathymetric surveys. In order to effectively utilize an airborne source of sound to infer bathymetry at full ocean depth, an important first step is to establish whether the signal intensity upon penetration into the water column is of sufficient strength to reflect off the ocean bottom and retain sufficient energy to induce measurable surface gravity capillary waves on the ocean surface. We therefore propose a multi-year measurement and analysis effort in a controlled environment such as a deep lake. This measurement effort will help understand thepossibility of detection of surface gravity waves induced by ensonification of the sea surface using an underwater acoustic source.This effort will ultimately yield insight into the potential of utilizing airborne sound sources as a tool to infer bottom depth, i.e., if surface gravity-capillary waves induced by an acoustic source can indeed be detected by airborne optical methods, then this opens up the possibility of ocean wave detection induced by an airborne source, thereby allowing for the inference of bottom parameters based on the induced capillary wave characteristics.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jun 09, 2021
- Source ID
- N000142112496
Entities
People
- Kaustubha Raghukumar
Organizations
- Integral Consulting (United States)
- Office of Naval Research
- United States Navy