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Brian Dushaw




Research Interests

Oceanography, Reciprocal Acoustic Tomography, Geophysical Inverse Theory


Dr. Dushaw began his career with the analysis and oceanographic interpretation of tomographic data collected during the 1987 Reciprocal Tomography Experiment (RTE87) in the North Pacific. For the past few years he has worked on the tidal variations detected tomographically during the 1991-1992 Acoustic Mid-Ocean Dynamics Experiment (AMODE) in the North Atlantic. The work on tides continues as part of the farfield component of the Hawaii Ocean Mixing Experiment (HOME).

In addition, Dr. Dushaw has taken the lead in the analysis of long-range acoustic data collected by SOSUS arrays during the Acoustic Thermometry of Ocean Climate (ATOC) project. Dr. Dushaw has authored numerous papers and reports on the oceanographic and acoustic problems addressed by ocean acoustic tomography. Dr. Dushaw was a postdoctoral research scientist at APL-UW from 1992-1994 and joined the Laboratory staff in 1994.

Department Affiliation



B.A. Physics, Occidental College, 1983

M.A. Physics, University of California, Davis, 1985

Ph.D. Physical Oceanography, Scripps Institution of Oceanography, 1992


2000-present and while at APL-UW

Resonant diurnal internal tides in the North Atlantic: 2. Modeling

Dushaw, B.D., and D. Menemenlis, "Resonant diurnal internal tides in the North Atlantic: 2. Modeling," Geophys. Res. Lett., 50, doi:10.1029/2022GL101193, 2023.

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16 Feb 2023

An unconstrained global ocean simulation for 2020 supports past observations of diurnal internal tides by acoustic tomography during the 1991–1992 Acoustic Mid-Ocean Dynamics Experiment in the Western North Atlantic. Explicitly representing the tides, the simulation reproduces the functional form and resonant state of K1 and O1 internal-tide standing waves, while providing a more realistic physical picture of them. The tomographic data were used to predict the tides in 2020. Not surprisingly, the characteristics of the barotropic and internal tides of the unconstrained simulation deviate from observations. The simulated barotropic tidal currents have excessive, irregular amplitude and lead the acoustic tidal predictions by about 2 hr. While internal-tide phase coherence is apparent, the simulated internal-tide variations were irregular in amplitude and phase, unlike the observations. The tomographic tidal measurements therefore provide a quantitative benchmark for improved model representation of tides, internal tides, and dissipation.

Rainfall at sea: Using underwater sounds of raindrops as a rain gauge for weather and climate

Ma, B.B., B.D. Dushaw, and B.M. Howe, "Rainfall at sea: Using underwater sounds of raindrops as a rain gauge for weather and climate," Acoust. Today, 18, 62-71.

28 Jul 2022

Surprises in physical oceanography: Contributions from ocean acoustic tomography

Dushaw, B.D., "Surprises in physical oceanography: Contributions from ocean acoustic tomography," Tellus A: Dyn. Meteorol. Oceanogr., 74, 33-67, doi:10.16993/tellusa.39, 2022.

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22 Mar 2022

The author has employed ocean acoustic tomography over the past 30 years to examine problems in physical oceanography, often with surprising results. Tomography offers an accurate measurement of current or sound speed (temperature) averaged over 100s to 1000s of kilometers. It has been used to test the fundamental equation for the speed of sound in seawater and to show that the normal state of the ocean has smooth, stable, well-behaved characteristics of acoustic propagation. This latter property has been challenging for ocean models to reproduce. Tomography measures barotropic tidal currents with remarkable accuracy, and it was used to discover that low-mode internal tides radiate far into the ocean’s interior, while retaining a surprising coherence. Tomographic measurements of large-scale temperature are complementary to point measurements by hydrography; the present observing system, relying principally on altimetry and Argo floats, has little skill in predicting the available tomographic data. The addition of tomographic data to the system would substantially reduce the uncertainty of ocean state estimates. The information content of integral acoustic observations is best exploited as a constraint on ocean models by data assimilation. The applications of tomography for measuring large-scale barotropic current, relative vorticity, and temperature have been under-exploited. Dedicated research programs, supporting novel acoustical oceanography, associated instrumentation development, and multidisciplinary research would further the applications of this observational approach.

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Acoustics Air-Sea Interaction & Remote Sensing Center for Environmental & Information Systems Center for Industrial & Medical Ultrasound Electronic & Photonic Systems Ocean Engineering Ocean Physics Polar Science Center