High-resolution acoustically informed maps of sound speed.

Area of Science:

• Oceanography
• Acoustics
• Geophysics

Background:

• Advancing oceanographic models require high-resolution in situ measurements for validation.
• Accurate spatiotemporal data are essential for informing and verifying complex oceanographic models.

Purpose of the Study:

• To map water masses at the New England shelf break using scientific echosounders and conductivity, temperature, and depth (CTD) data.
• To compare acoustically-inferred sound speed maps with those derived from interpolated CTD profiles.
• To assess the impact of different sound speed estimations on long-range acoustic propagation models.

Main Methods:

• Utilized scientific echosounders to map sound speed distribution.
• Collected water column properties using a single conductivity, temperature, and depth (CTD) profile.
• Performed two-dimensional interpolation of multiple CTD profiles to create a sound speed cross section.
• Parameterized long-range acoustic propagation models using sound speed profiles from both methods.

Main Results:

• Generated an acoustically-inferred map of sound speed at the New England shelf break.
• Quantified differences between acoustically-inferred and CTD-interpolated sound speed cross sections.
• Evaluated the impact of these differences on long-range acoustic propagation model outputs.

Conclusions:

• Scientific echosounders provide valuable data for mapping oceanographic features like water masses.
• Discrepancies in sound speed profiles can influence acoustic propagation model accuracy.
• Integrating acoustic and CTD data offers a robust approach for oceanographic model validation.