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Shani Rousseau, Eric Kunze, Richard Dewey, Kevin Bartlett, and John Dower

with up to 10 4 individuals per cubic meter ( De Robertis 2002 ; De Robertis et al. 2003 ; Parsons et al. 1983 ; Mackie and Mills 1983 ; Beveridge 2007 ), one to two orders of magnitude higher than typical open-ocean densities ( Greenlaw 1979 ) and corresponding to 0.1% by volume. We rely on these extensive past measurements to assume that the migrating acoustic backscatter layer is dominated by Euphausia pacifica . This species dominates the diel migrating acoustic backscatter signal (−78 to

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Tetjana Ross and Andone Lavery

sizes, and at typical depths of occurrence. The SO GLOBEC data suggest that diffusive-convection interfaces have already, inadvertently, been observed acoustically off the western Antarctic Peninsula. Acoustic observation of double-diffusive layers is highly complimentary to traditional microstructure or hydrographic measurements. The speed (typically one acoustic profile per second) and ease (no extra manpower) with which acoustics can sample the water column allows the observation of high

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Marwan Katurji, Bob Noonan, Peyman Zawar-Reza, Tobias Schulmann, and Andrew Sturman

nighttime vertical profiles of potential temperature and wind velocity. Near-target remote sensing measurement techniques such as integrated sound detection and ranging (sodar) and radio acoustic sounding system (RASS) systems are able to measure vertical profiles of temperature and wind velocity, which can be used to determine the boundary layer height and its stability at high temporal resolution. However, it is challenging to reduce the wealth of data to characterize the long-term behavior of the

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Renellys C. Perez, Silvia L. Garzoli, Christopher S. Meinen, and Ricardo P. Matano

et al. 2004 , 2009 ). Second, model T – S profiles are used to calculate a vertical sound speed profile, which is then integrated to obtain vertical acoustic travel time. Travel time is then related through lookup tables to geopotential height anomaly profiles (Φ CPIES ), simulating the use of CPIES. This indirect method is described in more detail in section 2d . For both measurement systems, the reconstructed MOC is given by where and is the sum of geostrophic velocity ( υ g ,array

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Jeffrey A. Nystuen, Marios N. Anagnostou, Emmanouil N. Anagnostou, and Anastasios Papadopoulos

, and sonars. These sounds must be correctly identified and classified in the sound spectra prior to the application of quantitative algorithms for the measurement of geophysical quantities such as rainfall rate and wind speed. As with other passive remote sensing techniques, the underwater acoustic measurement does not interfere with the process being monitored. Contrary to the surface-based sensors, the underwater sensor is away from the harsh environment of the air–sea interface. This has several

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Mahdi Razaz, Len Zedel, and Alex E. Hay

; Hay et al. 2012c , b , a ). The lack of suitable technologies for making measurements of flow and sediment transport within the bottom boundary layer encouraged development of a variety of coherent Doppler instruments [i.e., acoustic Doppler velocimeters (ADVs) and acoustic Doppler current profilers (ADCPs)] that are commercially available ( Lohrmann et al. 1995 ; Thurnherr 2010 ; Craig et al. 2011 ). Custom-built systems have been developed ( Stanton 1996 ; Zedel et al. 1996 ; Hurther and

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Kevin M. Rychert and Thomas C. Weber

would not interfere with downward-looking acoustic backscatter measurements of the bubbles. The pickup line does appear, however, in the lower portion of the acoustic data collected during the experiment ( Fig. 4 ). Fig . 4. (left) Echogram of match filtered data from ES18 transducer from all pings containing 2.4-mm N 2 bubbles. (right) Echogram from (left) overlaid with picked targets shown as white × marks. Acoustic data were collected with a Simrad ES18 split-beam echo sounder operating over a

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Ruixiang Zhao, Xiao-Hua Zhu, and Jae-Hun Park

resolution (e.g., 9.9156 days for TOPEX/Poseidon, Jason-1 , Jason-2 , and Jason-3 ). Therefore, removing the aliasing effects on altimeter measurements is important for application of sea surface height products ( Carrère and Lyard 2003 ; Park and Watts 2006 ; Stammer et al. 2000 ). Acknowledgments This study was supported by the Project of State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography (SOEDZZ1701), the Scientific Research Fund of SIO (JT1604 and JG

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J. E. Gaynor

Acoustic Doppler Measurement of Atmospheric Boundary LayerVelocity Structure Functions and Energy Dissipation Rates J. E. GA~o~Wa~e Propagation Laboratory, NOAA Environmental Re. search Laboratory, Bo~, Colo. ~0302(M~u~fipt received 2 April 1976, in revised form 24 J~ua~ 1977) ABSTRACT Acoustic echo sounder (echosonde) and meteorological tower measurements of the turbulent velocitystructure parameters D(r) and C~ and the rate of dissipation of turbulent

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A. C. Barbosa Aguiar, C. Ménesguen, S. Le Gentil, R. Schopp, and X. Carton

Carton et al. (2002) , maximal T and S within the cyclone were of 12°C and 36.2 psu, whereas in the meddy maxima values were of 12.5°C and 36.5 psu. In the same study, the thermohaline and velocity cores of the cyclone were located between 600 and 1300 m, at shallower depths than those of the meddies (750–1500 m), while the radii of the structures were comparable and about 30–35 km. In images of acoustic reflectivity of the water column, meddies appear imprinted as distinct elliptical contours

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