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Alexander Antonov, Anna Shabalina, Andrey Razin, Svetlana Avdyukhina, Ivan Egorov, and Vadim Agafonov

is a voltage applied between electrodes, and the electrical current passing between these electrodes is sensitive to the liquid motion produced by inertial forces. The sensors are very rugged due to the lack of delicate mechanical parts and provide a very high conversion coefficient in a low-frequency portion of the spectrum. The MTSS-2003 model is equipped with a force-balance feedback mechanism intended to optimize measurement stability under varying environmental parameters, including

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G. Fischer, T. Rossby, and D. Moonan

significant degree been relaxed thanks to a new technology whereby tiny high-frequency acoustic transmitters, each transmitting a unique identification (ID) code, are attached to fish. These devices are not DSTs in the usual sense, but when a fish tagged with such a transmitter passes within acoustic range of a moored stationary receiver, a record of that event is kept. While fish cannot be tracked continuously, this widely used technology gives valuable insight into the overall range and timing of their

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Zhongxiang Zhao, Eric A. D’Asaro, and Jeffrey A. Nystuen

generation and absorption. Instead, we present empirical fits to our sound measurements ( appendix B ; Fig. 11 ) in the hope that other researchers may find the method useful to interpret ocean acoustic data. 5. Discussion These data show both the spectrum of underwater ambient sound at very high wind speeds and its distribution with depth. An understanding of the spectrum requires detailed modeling of wave breaking, bubbles, and acoustics, for example, Deane and Stokes (2010) , which is beyond the

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Andreas Brand, Christian Noss, Christian Dinkel, and Markus Holzner

hydropower reservoir: Contribution from bubbling sediments . Environ. Sci. Technol. , 44 , 2419 – 2425 , doi: 10.1021/es9031369 . Dombroski, D. E. , and Crimaldi J. P. , 2007 : The accuracy of acoustic Doppler velocimetry measurements in turbulent boundary layer flows over a smooth bed . Limnol. Oceanogr. Methods , 5 , 23 – 33 , doi: 10.4319/lom.2007.5.23 . Glud, R. N. , Gundersen J. K. , Revsbech N. P. , and Jørgensen B. B. , 1994 : Effects on the benthic diffusive boundary layer

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Justine M. McMillan, Alex E. Hay, Rolf G. Lueck, and Fabian Wolk

turbulence quantities and their variability is needed to reduce the risk associated with uncertainty in the flow conditions. Yet, making turbulence measurements at middepth—that is, the depth range swept by the turbine blades—in high-flow tidal passages represents a significant challenge. Acoustic Doppler current profiler (ADCP) techniques are attractive because their remote measurement capability greatly simplifies the instrument deployment strategy (e.g., bottom mounted), and they can simultaneously

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Rick Salmon

spurious effects whenever the acoustic deformation radius c / f is less than the domain size. Repeating the experiments shown in Figs. 4a–d for the case c / f = 2 π of acoustic deformation radius equal to the domain size, we find this difference to be negligible. However, when c / f is much less than the domain size, the Arakawa and splitting solutions differ significantly; for example, Fig. 4e shows the vorticity at t = 100 for a splitting-algorithm solution in which c / f = 2 π /10

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Justine M. McMillan and Alex E. Hay

Lorke (2007) , who compared ε estimated from ADCP data via both the inertial dissipation method and the second-order SF method to results from collocated single-point measurements obtained with an acoustic Doppler velocimeter. In contrast to the results presented here, Lorke’s data were acquired in a low-dissipation-rate ( ε < 10 −8 W kg −1 ), bottom boundary layer lacustrine environment at short O (1) m range, using a Doppler profiler in pulse-coherent mode. In addition to the comparisons of

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Adrien Chabbey, Stuart Bradley, and Fernando Porté-Agel

1. Introduction Sodars are ground-based instruments using sound to obtain wind profiles in the lowest few hundred meters of the atmosphere. They transmit a short pulse in at least three upward directions. Spectral analysis of time-gated returns from turbulent scattering gives radial velocity components, and the beam geometry allows solving for vector wind components at each range gate ( Bradley 2007 ). One of the challenges with these instruments is the presence of competing background acoustic

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D. Randolph Watts, Maureen A. Kennelly, Kathleen A. Donohue, Karen L. Tracey, Teresa K. Chereskin, Robert A. Weller, and Ivan Victoria

1. Introduction We report here the results of an opportunity to compare current measurements from three different-model acoustic Doppler single-height current meters [Aanderaa recording current meter (RCM) 11, Aanderaa SEAGUARD, and Nortek Aquadopp] and the vector-measuring current meter (VMCM), whose accuracy has been previously characterized by tow tank tests ( Weller and Davis 1980 ). This new comparison was conducted on a moored deployment because for acoustic Doppler current sensors, a

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Valery F. Kramar, Evgeniya Baykova, Margarita Kallistratova, Rostislav Kouznetsov, and Sergei Kulichkov

in the ABL ( Kallistratova 1994 ; Emeis et al. 2007 ). Sodar-derived vertical velocities also provide a measure of convection intensity. For urban measurements, sodar has advantages over radar and lidar wind profilers. Unlike radar, it is not necessary to allocate an electromagnetic band for sodar, and relative to low-power lidar a sodar has a greater height range (higher-power lidar has greater range but requires further governmental approval). Moreover, the cost of a sodar unit is typically

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