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Jie Yang

Principal Physicist

Email

jieyang@apl.washington.edu

Phone

206-685-7617

Department Affiliation

Acoustics

Publications

2000-present and while at APL-UW

Direct measurements of sediment sound speed and attenuation in the frequency band of 2–8 kHz at the Target and Reverberation Experiment Site

Yang, J., and D. Tang, "Direct measurements of sediment sound speed and attenuation in the frequency band of 2–8 kHz at the Target and Reverberation Experiment Site," IEEE J. Ocean. Eng., 42, 1102-1109, doi:10.1109/JOE.2017.2714722, 2017.

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1 Oct 2017

The sediment acoustic-speed measurement system is designed to measure in situ sediment sound speed and attenuation within the surficial 3 m of sediments in the frequency band of 2–8 kHz. Measurements were carried out during the Target and Reverberation EXperiment 2013 (TREX13) off Panama City, FL, USA. During TREX13, nine deployments at five selected sites were made along the 20-m isobath, termed the main reverberation track. The sediment types at the five selected sites ranged from coarse sand to a mixture of soft mud over sand, and the measured results show a spread of 80 m/s in sediment sound speed among the different types of sediments for all frequencies. Between 2–8 kHz, about 3% dispersion was observed at the sandy sites, whereas little dispersion was observed at the sites with mud. Preliminary attenuation results show 0.5–3.3 dB/m at the sandy sites, and 0.5–1.0 dB/m at the sites with mud in the same frequency band.

A normal mode reverberation and target echo model to interpret towed array data in the target and reverberation experiments

Ellis, D.D., J. Yang, J.R. Preston, and S. Pecknold, "A normal mode reverberation and target echo model to interpret towed array data in the target and reverberation experiments," IEEE J. Ocean. Eng., 42, 344-361, doi:10.1109/JOE.2017.2674106, 2017.

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1 Apr 2017

Reverberation measurements obtained with towed arrays are a valuable tool to extract information about the ocean environment. By superimposing a polar plot of reverberation beam time series on bathymetry maps, bottom features (often uncharted) can be located. As part of Rapid Environmental Assessment exercises, Preston and Ellis used directional reverberation measurements to extract environmental information using model-data comparisons. This early work used range-independent (flat bottom) ray-based models for the model-data comparisons, while current work includes range-dependent models based on adiabatic normal modes. Here, we discuss a range-dependent shallow-water reverberation model using adiabatic normal modes that has been developed to handle bottom scattering and clutter echoes in a range-dependent environment. Beam time series similar to those measured on a horizontal line array can be produced. Comparisons can then directly be made with data, features identified, and estimates of the scattering obtained. Of particular interest will be data obtained on the triplet line array during the 2013 Target and Reverberation EXperiments in the Gulf of Mexico off Panama City, FL, USA, where interesting effects in sea bottom sand dunes were observed. Particular attention has been paid to calibration to get estimates of scattering strengths. In addition to the reverberation, a preliminary investigation of the target echo is presented.

Rainfall measurements in the North Atlantic Ocean using underwater ambient sound

Yang, J., W.E. Asher, and S.C. Riser, "Rainfall measurements in the North Atlantic Ocean using underwater ambient sound," Proc., IEEE/OES China Ocean Acoustics Symposium, 9-11 January, Harbin, China (IEEE/OES, 2016).

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8 Aug 2016

Quantification of rainfall over the ocean is critical in understanding the global hydrological cycle. However, oceanic rain has proven difficult to measure due to problems associated with platform motion and flow distortion combined with the spatial and temporal variability of rainfall itself. Passive acoustic rain gauges avoid these issues by using the underwater sound generated by raindrops on the ocean surface to detect and quantify rainfall. In this paper, the operating principles for and data from the Passive Aquatic Listener (PAL), which uses underwater ambient sound to measure rainfall rate and wind speed, are presented. PAL was incorporated onto thirteen Argo profilers that were deployed in September, 2012 as part of the US National Aeronautics and Space Administration-sponsored Salinity Processes in the Upper ocean Regional Studies (NASA SPURS) field experiment in the North Atlantic Ocean. PAL-Argo was initially deployed within a 200 km x 200 km box, PAL-Argos now cover a 1600-km x 600-km region, and continue to telemeter rain rate and wind speed data. Comparisons of these PAL data with in situ and satellite measurements show good agreement for both rain rate and wind speed. Seasonal and inter-annual variability of wind and rain fields in the region are also presented.

More Publications

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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