Acoustic characterization of the New England Seamounts region.

Abstract

The oceanographic environment surrounding the New England Seamounts frequently involves the complex interaction of the colder Slope Sea waters with the warmer Sargasso Sea waters, where a meandering frontal boundary is caused by the Gulf Stream. The sound speed profiles and associated available acoustic propagation paths differ significantly on either side of the Gulf Stream. Regional historical temperature profile data gathered from the Argo float program are used to investigate common acoustic trends associated with the region. A clustering algorithm organizes the dataset by the three dominant water temperature profile types, allowing for the direct investigation of Slope Sea, Gulf Stream, and Sargasso Sea environments. Cycle distance and propagation path type are employed as acoustic metrics to assess common depth-dependent features. Comparison of the metrics calculated for Argo data with those for the closest Hybrid Coordinate Ocean Model predictions indicate the existence of spatiotemporal features that are present in the observational data but not in the numerical ocean model predictions. Small biases in modeled temperature fields can result in the absence of common acoustic propagation features found in the data.