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Valery M. Melnikov, Richard J. Doviak, Dusan S. Zrnić, and David J. Stensrud

congestus clouds prior to the onset of thunderstorms. Our analysis of Bragg scatter structures shows that the tops of the lowest echo layers correlate well with estimates of the CBL depth obtained from atmospheric rawinsonde soundings. Radar data also indicate local inhomogeneities in the CBL. Radar observations of CBL depth could provide an important constraint on the changes in water vapor, pollutants, and turbulence within the boundary layer. Current model predictions of CBL depth often differ from

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

values are averaged over 30 min, and each unit provides average vertical profiles that are freely available in real time on the IAPh ( ) and Zvenigorod ( ) Internet sites. Fig . 1. Locations of the Mosecomonitoring stations. The external ring of roads is the Moscow administrative boundary. Red circles mark stations. Only the numbered stations were used in the current research. See appendix A for further description of the stations. The circle

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Elías Lau, Scott McLaughlin, Frank Pratte, Bob Weber, David Merritt, Maikel Wise, Gary Zimmerman, Matthew James, and Megan Sloan

1. Introduction Radar wind profilers (RWPs) with an operating frequency around 1 GHz are widely used to probe the boundary layer (BL). Although they do not offer the height coverage of radars that operate at very high frequency (VHF) and at the lower UHF range, their antennas are relatively smaller and can effectively measure winds in the BL. BL RWPs are routinely used in atmospheric research and operational applications. Examples of atmospheric research include determination of boundary layer

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Qing Yang, Larry K. Berg, Mikhail Pekour, Jerome D. Fast, Rob K. Newsom, Mark Stoelinga, and Catherine Finley

longwave radiation ( Mlawer et al. 1997 ). For the current version of WRF, the surface-layer options generally are tied to particular boundary layer schemes. The MYJ and UW PBL schemes were run with the Eta Model ( Janjić 1996 , 2002 ) surface-layer scheme, and the YSU scheme was run with the fifth-generation Pennsylvania State University–National Center for Atmospheric Research Mesoscale Model (MM5) similarity-theory surface-layer scheme ( Skamarock et al. 2008 ). Three sets of simulations, denoted

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A. B. White, M. L. Anderson, M. D. Dettinger, F. M. Ralph, A. Hinojosa, D. R. Cayan, R. K. Hartman, D. W. Reynolds, L. E. Johnson, T. L. Schneider, R. Cifelli, Z. Toth, S. I. Gutman, C. W. King, F. Gehrke, P. E. Johnston, C. Walls, D. Mann, D. J. Gottas, and T. Coleman

are a critical component of Earth’s energy budget ( Zhu and Newell 1998 ). In addition, climate projections suggest that the intensity and frequency of AR events in California may increase in response to global climate change ( Dettinger 2011 ). An example of an AR impacting the U.S. West Coast as viewed from satellites ( Wick et al. 2013 ) is shown in Fig. 1 . The continents are black in Fig. 1 because the satellite microwave retrievals of water vapor that work over the oceans currently are

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Andreas Rettenmeier, David Schlipf, Ines Würth, and Po Wen Cheng

additional remote sensing device—for example, a sodar or a lidar system—installed on the ground as a supplement to a meteorological mast. This remote sensing device is able to measure the wind speed across the whole rotor area up to tip height and is able to take shear effects into account ( Wagner 2010 ). It will be used for future power performance testing on flat terrain, as this approach is fed into the revision of the current standard. Using a scanning lidar, horizontally mounted on the nacelle of a

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Laura Bianco, Daniel Gottas, and James M. Wilczak

482-MHz wind profiling radar, and found that it effectively identified and eliminated the bird-contaminated data while most often finding the true atmospheric signal. In the current study, we apply the same algorithm to data from 915-MHz wind profiling radars. The sensitivity of a wind profiler to migrating birds depends on a number of profiler characteristics, including its beamwidth, range resolution, and wavelength ( Wilczak et al. 1995 ; Merritt 1995 ). Referring to our case, contamination

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C. R. Wood, R. D. Kouznetsov, R. Gierens, A. Nordbo, L. Järvi, M. A. Kallistratova, and J. Kukkonen

layer have not been thoroughly addressed to date ( Beyrich et al. 2012 ). Moreover, despite the fact that scintillometry gives quite promising results for large heat fluxes in the convective atmospheric boundary layer ( Moene et al. 2009 ), its performance for small sensible heat fluxes (especially under stable stratification even in the surface layer) is not very good ( Andreas 2012 ). The stable cases are of special interest for air quality applications, because small changes in stratification can

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Mikael Sjöholm, Nikolas Angelou, Per Hansen, Kasper Hjorth Hansen, Torben Mikkelsen, Steinar Haga, Jon Arne Silgjerd, and Neil Starsmore

rotorcraft optimization regarding, for example, minimizing the risk to aircraft and personnel when operating in a search and rescue role, and can contribute to the understanding about brownout and similar phenomena. The current implementation of the technology can measure the line-of-sight velocity in the range from −21 up to 18 m s −1 . However, this velocity range is not a fundamental limit, since it can be extended by, for example, a higher center frequency shift combined with a higher sampling rate

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