Ocean Acoustics Overview

Principles

Definition

Ocean acoustics is the scientific field concerned with the study of sound in the ocean, including its generation, propagation, reflection, scattering, and absorption. This discipline investigates how acoustic waves behave within the complex marine environment, providing fundamental insights into ocean properties and enabling crucial applications in communication, navigation, sensing, and the study of marine organisms.

Ontological type

Physical Principles

Engineering Applications

Modeling and Simulation

Key developments

Key Figures

Environment-Aware Propagation era

Arye Nehorai [1] was associated with Stanford University [3] and Yale University [4] during the Environment-Aware Propagation era. His key contributions include MUSIC, maximum likelihood, and Cramer-Rao bound methods [6], which advanced array processing and parameter estimation in ocean acoustics and supported the development of environment-aware localization and detection in long-range propagation. Petre Stoica [2] was affiliated with Yale University [4] and the University of Bucharest [5] during this era. His contributions, as reflected in the same MUSIC, maximum likelihood, and Cramer-Rao bound work [6], provided rigorous theory, practical estimation methods, and influenced subsequent ocean-acoustic signal processing and matched-field processing.

Signal Processing and Inversion era

Jeroen Tromp [1] is a prominent researcher whose work in this era spans Harvard University [3] and the University of California, San Diego [4]. His key contributions for the era include the seismic-tomography framework and adjoint methods culminating in time reversal and related kernel concepts as described in the 2004 paper Seismic tomography, adjoint methods, time reversal and banana-doughnut kernels [7], which advanced robust imaging and inversion in complex oceanic waveguides. Darrell R. Jackson [2] is associated with University of Washington [5] and Pennsylvania State University [6], reflecting his role across major ocean-acoustics centers in this era. His notable contribution in this period is the experimental demonstration of an acoustic time-reversal mirror via phase conjugation in the ocean in the 1998 paper Phase conjugation in the ocean: Experimental demonstration of an acoustic time-reversal mirror [8], which showcased the practical viability of phase-conjugate techniques for focusing and imaging in reverberant ocean environments.

Distributed Multimodal Sensing era

Biondo Biondi [1] is a leading researcher associated with Stanford University [3] and The University of Texas at Austin [4] during the Distributed Multimodal Sensing era (2010-2024). He co-authored Fiber‐Optic Network Observations of Earthquake Wavefields [7], demonstrating distributed fiber sensing of seismic wavefields and enabling high-resolution, long-range measurements that underpin real-time sensing and scalable monitoring in this era. Douglas S. Dreger [2] is affiliated with University of California, Berkeley [5] and California Institute of Technology [6] in this era. As co-author of Fiber‐Optic Network Observations of Earthquake Wavefields [7], he helped establish the fiber-based approach for dense spatial measurements of wavefields, providing critical data for networked ocean observatories and ecological surveillance that the era aims to enable.