BRS Sound Exposure Modeling Tool: A system for planning, visualization and analysis

The Behavioral Research Studies (BRS) Sound Exposure Modeling Tool has been developed to provide both planning and near real-time guidance for Controlled Exposure Experiments (CEEs), first in the Southern California Bight, and then in the Gulf Stream area off Cape Hatteras. Transmission loss from a mid-frequency sound source is estimated using Navy and NOAA acoustic propagation models and environmental databases. A Navy version of the RAM parabolic equation model and a ray-theory based model Bellhop are used to cover long-range and short-range propagation scenarios, respectively. The tool operates in a MATLAB C computing environment and uses a simple parallelization scheme to speed up the processing. The Graphical User Interface and design of the output graphical products have been tuned based on feedback from the use of the model in the field. In addition to operational use for estimating the sound exposure on a tagged whale, the developed tool can be applied for reconstructing sonar received level to verify and analyze results of both planned and opportunistic BRS experiments, as well as to study sensitivity of the acoustic propagation modeling to uncertainties and spatio-temporal resolution of the model input.