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Chris Jones

Senior Engineer

Email

cjones@apl.washington.edu

Phone

206-543-1615

Biosketch

Chris Jones's research interests include both forward inverse problems in ocean acoustics. He is involved in research on scattering from and within ocean sediments, as well as inversions of acoustic signals to examine biological activity, hydrothermal plume flow, and particle size distributions.

Publications

2000-present and while at APL-UW

Tracking beaked whales with a passive acoustic profiler float

Matsumoto, H., C. Jones, H. Klinck, D.K. Mellinger, R.P. Dziak, and C. Meinig, "Tracking beaked whales with a passive acoustic profiler float," J. Acoust. Soc. Am., 133, 731-740, 2013.

More Info

1 Feb 2013

Acoustic methods are frequently used to monitor endangered marine mammal species. Advantages of acoustic methods over visual ones include the ability to detect submerged animals, to work at night, and to work in any weather conditions. A relatively inexpensive and easy-to-use acoustic float, the QUEphone, was developed by converting a commercially available profiler float to a mobile platform, adding acoustic capability, and installing the ERMA cetacean click detection algorithm of Klinck and Mellinger [(2011). J. Acoust. Soc. Am. 129(4), 1807–1812] running on a high-power DSP. The QUEphone was tested at detecting Blainville's beaked whales at the Atlantic Undersea Test and Evaluation Center (AUTEC), a Navy acoustic test range in the Bahamas, in June 2010. Beaked whale were present at AUTEC, and the performance of the QUEphone was compared with the Navy's Marine Mammal Monitoring on Navy Ranges (M3R) system. The field tests provided data useful to evaluate the QUEphone's operational capability as a tool to detect beaked whales and report their presence in near-real time. The range tests demonstrated that the QUEphone's beaked whale detections were comparable to that of M3R's, and that the float is effective at detecting beaked whales.

Multibeam sonar observations of hydrothermal flows at the Main Endeavour Field

Rona, P.A., K.G. Benis, C.D. Jones, and D.R. Jackson, "Multibeam sonar observations of hydrothermal flows at the Main Endeavour Field," J. Acoust. Soc. Am., 129, 2373, doi:10.1121/1.3587686, 2011.

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1 Apr 2011

The Cabled Observatory Vent Imaging Sonar has been deployed at the Main Endeavour Node of the Canadian Neptune cabled observatory and has acquired data on plume and diffuse hydrothermal flows. Based on the Reson 7125 multibeam sonar and operating at 200 and 400 kHz, two-dimensional and three-dimensional time series are produced using plume backscattering, Doppler shift, and acoustic scintillation. Hydrothermal plumes and diffuse flow are important as agents of transfer of heat, chemicals, and biological material from the mantle and crust into the ocean in quantitatively significant amounts. High-frequency sonar measurements offer the possibility of inversion to obtain fluxes of central importance in these processes. Long-term time series, obtainable in cabled systems, allow observations of hydrothermal response to tidal, tectonic, and volcanic forcing. Examples will be given of plume bending due to currents, determination of entrainment of ambient water, time variation of diffuse flows, and Doppler determination of volume flux.

Basis of acoustic discrimination of chinook salmon from other salmons by echolocating Orcinus orca

Au, W.W.L., J.K. Horne, and C. Jones, "Basis of acoustic discrimination of chinook salmon from other salmons by echolocating Orcinus orca," J. Acoust. Soc. Am., 128, 2225-2232, doi:10.1121/1.3473697, 2010.

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1 Oct 2010

The "resident" ecotype of killer whales (Orcinus orca) in the waters of British Columbia and Washington State have a strong preference for Chinook salmon even in months when Chinook comprise less than about 10% of the salmon population. The foraging behavior of killer whales suggests that they depend on echolocation to detect and recognize their prey. In order to determine possible cues in echoes from salmon species, a series of backscatter measurements were made at the Applied Physics Laboratory (Univ. of Wash.) facility on Lake Union, on three different salmon species using simulated killer whale echolocation signals. The fish were attached to a monofilament net panel and rotated while echoes were collected, digitized and stored on a laptop computer. Three transducer depths were used; same depth, 22 and 45 degrees above the horizontal plane of the fish. Echoes were collected from five Chinook, three coho and one sockeye salmon. Radiograph images of all specimens were obtained to examine the swimbladder shape and orientation. The results show that echo structure from similar length but different species of salmon were different and probably recognizable by foraging killer whales.

More Publications

Midfrequency backscatter imaging of fish schools in a shallow water waveguide

Jones, C.D., and D.R. Jackson, "Midfrequency backscatter imaging of fish schools in a shallow water waveguide," J. Acoust. Soc. Am., 125, 2550, 2009.

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1 Apr 2009

In this experimental effort, field data and modeling are used to investigate backscatter imaging of schools of pelagic fish in a shallow water oceanic waveguide. Two-dimensional (2-D) circular images of an oceanic waveguide are created using a monostatic circular receiving array and vertical line array source (12 kHz) deployed from a stationary ship. Horizontal multibeam images of a radial (depth integrated) cross section of the ocean are formed with targets and reverberation structure observed at ranges up to several km. Examples of waveguide images are presented for data taken in the Puget Sound of Washington State. In some instances, the backscatter from aggregations of fish was observed to be higher than the reverberation; in other cases, fish schools could not be resolved. Fish school locations were independently observed by vertical echo sounding. Preliminary experimental results are shown to illustrate the potential of resolving the 2-D horizontal structure of aggregations of fish using such methods. Modeling is used to interpret the effects of waveguide propagation on imaging. Operational issues related to using waveguide imaging for fisheries research and signal processing issues related to waveguide imaging will be discussed.

Mid-frequency pelagic imaging multi-beam sonar

Jones, C.D., "Mid-frequency pelagic imaging multi-beam sonar," J. Acoust. Soc. Am., 123, 3211, doi:10.1121/1.2933387, 2008.

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1 May 2008

A unique circular array multi-beam sonar is used to investigate volumetric imaging of pelagic marine environments. Imaging of a radial volume of the ocean up to a kilometer in range and at 8–12kHz will be discussed, focusing mainly on the imaging of large aggregations of fish in shallow water. Several imaging geometries are presented including backscatter imaging in a shallow water waveguide used to resolve the two-dimensional horizontal structure of large fish schools, and the autonomous deployment of the sonar in a fixed location to create a time series of images and observations of variability over a 24 hour period. The potential for new imaging geometries will be explored including vertical profiling to create volumetric images of different pelagic zones in the ocean. Operational issues related to specific scientific question, and signal processing issues related to circular arrays will be discussed. Preliminary field data will be presented.

Acoustic Environment of Haro Strait: Preliminary Propagation Modeling and Data Analysis

Jones, C.D., and M.A. Wolfson, "Acoustic Environment of Haro Strait: Preliminary Propagation Modeling and Data Analysis," APL-UW TM 3-06, August 2006.

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30 Aug 2006

Field measurements and acoustic propagation modeling for the frequency range 1–10 kHz are combined to analyze the acoustic environment of Haro Strait of Puget Sound, an area frequented by the southern resident killer whales. Haro Strait is a highly variable acoustic environment with active commercial shipping, whale watching, and Naval activity. Southern resident killer whales are of unique public concern in this area because of increasing anthropogenic noise levels that may interfere with the animal's foraging strategies and behavior. Predictive acoustic modeling in combination with field measurements can be used as a tool for understanding the mechanisms of impact and assessment of the risk, providing a quantitative evaluation of sound source levels in the context of complicated acoustic environments, changing background sound levels, and emerging management issues. Of principle concern here is background sound levels created by commercial shipping traffic or other persistent sound sources that propagate from the main shipping channel. The scope of the modeling effort encompasses numerical modeling of transmission loss and propagation at ranges of less than 10 km. Preliminary modeling results are analyzed and compared with recordings of ship noise collected in the spring/summer of 2004.

A method for Doppler acoustic measurement of black smoker flow fields

Jackson, D.R., C.D. Jones, P.A. Rona, and K.G Bemis, "A method for Doppler acoustic measurement of black smoker flow fields," Geochem. Geophys., Geosyst., 4, 10.1029/2003GC000509, 2003.

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14 Nov 2003

A method is developed for using multibeam sonar to map the flow velocity field of black smoker plumes. The method is used to obtain two-dimensional cross-sectional maps of vertical velocity, but is capable of mapping velocity in three dimensions. This is in contrast to conventional current meters, which measure only at several points and acoustic Doppler current profilers, whose diverging beams cannot readily map the interior of a plume. Geometric corrections are used to estimate the vertical component of velocity, compensating for ambient current. The method is demonstrated using data from the main plume at the Grotto vent complex in the Main Endeavour Field, Juan de Fuca Ridge, and the errors due to noise, signal fluctuations, and fluctuations in plume structure are estimated.

Underwater acoustic communication using passive phase conjugation

Rouseff, D., W.L.J. Fox, D.R. Jackson, and C.D. Jones, "Underwater acoustic communication using passive phase conjugation," MTS/IEEE Oceans 2001, 5-8 November, Honolulu, HI, doi:10.1109/OCEANS.2001.968344 (IEEE, 2001).

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5 Nov 2001

A new method for underwater acoustic communication called passive phase conjugation is evaluated. The method begins with a source transmitting a single probe pulse. After waiting for the multipathed arrivals to clear, the source then transmits the data stream. At each element in the distant receiving array, the received probe is cross-correlated with the received data stream. This cross-correlation is done in parallel at each array element and the results are summed across the array to achieve the final communication signal suitable for demodulation. The parallel processing makes the method computationally efficient and allows near real-time communication.

Underwater acoustic communication by passive phase conjugation: Theory and experimental results

Rouseff, D., D.R. Jackson, W.L.J. Fox, C.D. Jones, J.A. Ritcey, and D.R. Dowling, "Underwater acoustic communication by passive phase conjugation: Theory and experimental results," IEEE J. Ocean. Eng., 26(4), 821-831, 2001.

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1 Oct 2001

A new method for coherent underwater acoustic communication called passive phase conjugation is evaluated. The method is so named because of conceptual similarities to active phase conjugation methods that have been demonstrated in the ocean. In contrast to active techniques, however, the array in passive phase conjugation needs only receive. The procedure begins with a source transmitting a single probe pulse. After waiting for the multipathed arrivals to clear, the source then transmits the data stream. At each element in the distant receiving array, the received probe is cross-correlated with the received data stream. This cross-correlation is done in parallel at each array element and the results are summed across the array to achieve the final communication signal suitable for demodulation. As the ocean changes, it becomes necessary to break up the data stream and insert new probe pulses. Results from an experiment conducted in Puget Sound near Seattle are reported. Measurements were made at multiple ranges and water depths in range-dependent environments.

Underwater acoustic communication by passive phase conjugation: Theory and experiment

Jackson, D.R., D. Rouseff, W.L.J. Fox, C.D. Jones, J.A. Ritcey, and D.R. Dowling, "Underwater acoustic communication by passive phase conjugation: Theory and experiment," J. Acoust. Soc. Am., 108, 2607, doi:10.1121/1.1289207, 2000.

More Info

1 Nov 2000

A new method for coherent underwater communication called passive phase conjugation is evaluated. The technique takes its name because of conceptual similarities to active phase conjugation methods that have been demonstrated in the ocean [Kuperman et al., J. Acoust. Soc. Am. 103, 25-40 (1998)]. In contrast to active techniques, however, the array in passive phase conjugation need only receive. This makes the method plausible for scenarios where spatially compact sources might be communicating to a distant receive-only array. Compared to other approaches for coherent communication, the computational burden is low allowing the method to be evaluated in the field in nearly real-time. Results from an experiment conducted in Puget Sound near Seattle in May 2000 are reported. Various modulation schemes and array geometries were employed. Measurements were made at several ranges and water depths in a range-dependent environment.

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
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