Brian Dushaw

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Since it was first proposed in the late 1970's (Munk and Wunsch 1979, 1982), ocean acoustic tomography has evolved into a remote sensing technique employed in a wide variety of physical settings. In the context of long-term oceanic climate change, acoustic tomography provides integrals through the mesoscale and other high-wavenumber noise over long(More)
We examine statistical and directional properties of the ambient noise in the 10-100 Hz frequency band from the NPAL array. Marginal probability densities are estimated as well as mean square levels, skewness and kurtoses in third octave bands. The kurotoses are markedly different from Gaussian except when only distant shipping is present. Extremal levels(More)
The accuracy of state-of-the-art global barotropic tide models is assessed using bottom pressure data, coastal tide gauges, satellite altimetry, various geodetic data on Antarctic ice shelves, and independent tracked satellite orbit perturbations. Tide models under review include empirical, purely hydrodynamic (" forward "), and assimilative dynamical,(More)
(2003). Field experiments show that acoustic pingers reduce marine mammal by-catch in the California drift gill net fishery. Mar. (1997). Exposure to sublethal blast overpressure reduces the food intake and exercise performance of rats.
– Since it was first proposed in the late 1970s (Munk and Wunsch, 1979, 1982), ocean acoustic tomography has evolved into a multipurpose remote-sensing measurement technique that has been employed in a wide variety of physical settings. In the context of long-term oceanic climate change, acoustic tomography provides integrals through the mesoscale and other(More)
The application of ocean acoustic tomography in Fram Strait requires a careful assessment of the accuracy to which estimates of sound speed from tomography can be converted to estimates of temperature. The Fram Strait environment is turbulent, with warm, salty, northward-flowing North Atlantic water interacting with cold, fresh, southward-flowing Arctic(More)
Acoustic tomography systems have been deployed in Fram Strait over the past decade to complement existing observing systems there. The observed acoustic arrival patterns are unusual, however, consisting of a single, broad arrival pulse, with no discernible repeating patterns or individual ray arrivals. The nature of these arrivals is caused by vigorous(More)
LONG-TERM GOALS • To evaluate feasibility and determine physical limits of performance of a passive acoustic system for characterization of a time-varying ocean where ambient acoustic noise is utilized as a probing signal. • To develop a passive remote sensing technique for acoustic characterization of oceanic currents. OBJECTIVES 1. To demonstrate(More)