This research is one component of a team effort with the goal of using existing science to represent the uncertainty in the tactical and environmental picture to improve acoustic tracking and localization of submarines. The project objective was to develop an end-to-end system that incorporates the uncertainties in the sound speed field, the bottom sediment properties, and the internal wave field, to determine the ultimate uncertainty in the estimation of undersea targets as would be detected on board a submarine. This part of the project focused on characterizing the perturbations caused by the internal wave field and its effect on acoustic propagation.