Accession Number:

ADA616530

Title:

Out-of-Plane Effects in Ocean Acoustics

Descriptive Note:

Corporate Author:

HEAT LIGHT AND SOUND RESEARCH INC LA JOLLA CA

Personal Author(s):

• Porter, Michael B.

Report Date:

2014-09-30

Pagination or Media Count:

9.0

Abstract:

In recent years tremendous progress has been made in modeling both the ocean environment and its effects on sound. Global models of the 4D space-time oceanography are produced both regularly and frequently. They are also readily available through FNMOC Reachback Support. In fact, rather than just a deterministic forecast, the oceanographic models routinely provide ensemble forecasts representing a fuzzy ocean, i.e., a distribution of possible realizations. It is interesting that the sound models that propagate through such fields have really not kept up. Three-dimensional propagation modeling has, of course, been a research topic of interest for many decades. However, it has never really become a mainstream activity, partly because it used to be too time-consuming, partly because the environmental information was not available. The community has now clearly recognized that the time is right to take a step up in the modeling capability and do fully three-dimensional modeling using ensemble forecasts of the ocean structure. The goal of this research is to do exactly that, leveraging the BELLHOP3D Gaussian beam tracing code. Further enhancements will be made to BELLHOP3D however, a particular focus will be the assessment of 3D effects in various upcoming experiments. In the last year we have focused on underwater acoustic communications as the application of interest.

Descriptors:

• *OCEANS
• *SOUND
• FORECASTING
• PROPAGATION
• THREE DIMENSIONAL

Subject Categories:

• Physical and Dynamic Oceanography
• Acoustics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE