Three-dimensional mapping of evolving internal waves during the Shallow Water 2006 experiment

Area of Science:

• Oceanography
• Acoustics
• Geophysics

Background:

• Sound speed variability in shallow water significantly impacts acoustic propagation.
• Internal waves (IW) are a major cause of this variability, creating complex 3D sound speed structures.
• Accurate characterization of IW fields is essential for acoustic modeling.

Purpose of the Study:

• To present a strategy for reconstructing a time-varying, three-dimensional (3D) internal wave (IW) temperature field.
• To demonstrate the impact of IWs on acoustic propagation in shallow water environments.

Main Methods:

• Simultaneous measurements using a farm of thermistor strings for dense subsurface temperature data.
• Ship-based radar observations to capture IW surface expressions.
• Reconstruction of the 3D IW temperature field over multiple kilometers.
• Integration of the reconstructed temperature field into a 3D acoustic model.

Main Results:

• Successfully reconstructed a detailed 3D temperature field influenced by internal waves.
• Demonstrated the significant impact of this reconstructed field on acoustic propagation patterns.
• Validated the strategy using data from the Shallow Water 2006 experiment.

Conclusions:

• The presented strategy effectively captures the spatio-temporal dynamics of internal waves.
• Accurate 3D sound speed field reconstruction is vital for understanding acoustic fluctuations in shallow waters.
• This approach enhances the fidelity of acoustic propagation modeling in dynamic ocean environments.