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Ronny Engelmann, Ulla Wandinger, Albert Ansmann, Detlef Müller, Egidijus Žeromskis, Dietrich Althausen, and Birgit Wehner

of flux parameterizations in mesoscale and general circulation models. Such observations can only be done with remote sensing instruments that provide the parameters of interest with high accuracy (<5%–10%) and with a spatial resolution of the order of 50 m and a temporal resolution of a few seconds. Remote measurements of turbulent fluxes in the planetary boundary layer were first shown by Senff et al. (1994) . A water vapor differential absorption lidar (DIAL) was combined with a radar radio

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Rod Frehlich, Yannick Meillier, and Michael L. Jensen

technique for these situations is selecting a suitable averaging interval to define the mean and turbulent quantities for both in situ observations ( Kaimal and Finnigan 1994 ; Mahrt 1998 ; Vickers and Mahrt 2003 ) and remotely sensed measurements such as Doppler lidar ( Banta et al. 2003 , 2006 ). The optimal choice of the averaging time is difficult to quantify when there is no obvious scale separation between the forcing mechanisms and turbulence. The effects of the larger mesoscale forcing on

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P. C. S. Devara, P. E. Raj, K. K. Dani, G. Pandithurai, M. C. R. Kalapureddy, S. M. Sonbawne, Y. J. Rao, and S. K. Saha

parameter, and not many observations are available in the literature. In the present paper, we have made an attempt to infer the aerosol shape qualitatively from the lidar depolarization ratio. Also, by utilizing the unique facility (the switching of the state of polarization of the laser pulse energy between parallel and perpendicular) available with the DPMPL, datasets are being collected to undertake detailed analyses of cloud composition [such as determination of water, ice, or mixed phase and the

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Steven E. Koch, Cyrille Flamant, James W. Wilson, Bruce M. Gentry, and Brian D. Jamison

wave displaying lesser amplitudes. Density currents, bores, and solitons were observed repeatedly by a multitude of ground-based and airborne remote sensing systems during the 6-week field phase of IHOP_2002. One purpose of this paper is to determine the extent to which the structure of bores and solitons is consistent between observations made by airborne differential absorption lidar (DIAL), ground-based Doppler radar, and Doppler lidar. A second objective is to extend previous applications of

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Reginald J. Hill, W. Alan Brewer, and Sara C. Tucker

1. Introduction The National Oceanic and Atmospheric Administration (NOAA)/Earth System Research Laboratory (ESRL) has developed two coherent Doppler lidars to study atmospheric boundary layer dynamics (see Grund et al. 2001 ; Brewer et al. 1998 ). Typically these systems perform low–elevation angle scans to determine wind speed and direction and to quantify turbulence with high temporal and vertical resolution. This is accomplished by operating with a high pulse-repetition frequency and

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Matthias Grzeschik, Hans-Stefan Bauer, Volker Wulfmeyer, Dirk Engelbart, Ulla Wandinger, Ina Mattis, Dietrich Althausen, Ronny Engelmann, Matthias Tesche, and Andrea Riede

vapor observations on mesoscale weather forecasting. During LAUNCH, what is to our knowledge the first time, a network of 13 water vapor Raman lidar systems was operated in an area covering central Europe so that their impact over a larger domain could be investigated by means of observing system experiments (OSEs). As Raman lidar systems have especially high vertical resolution and accuracy, they are expected to be well-suited as basis for future ground-based networks, which is one of the subjects

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V. Bellantone, I. Carofalo, F. De Tomasi, M. R. Perrone, M. Santese, A. M. Tafuro, and A. Turnone

Radiation II campaign. Combined observations with an advanced aerosol water vapor temperature Raman lidar and a sun photometer have been used by Müller et al. (2003) for a detailed characterization of geometrical and optical properties of a continental-scale Saharan dust event observed over Leipzig, Germany. The complementary use of three-dimensional chemical transport models and satellite observations has been illustrated by Robles Gonzalez et al. (2003) to show that models can provide information

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Thierry Leblanc, I. Stuart McDermid, and Robin A. Aspey

. Meteor. Soc. , 114 , 1471 – 1484 . 10.1002/qj.49711448406 Vömel, H. , David D. , and Smith K. , 2007 : Accuracy of tropospheric and stratospheric water vapor measurements by the Cryogenic Frost point Hygrometer (CFH): Instrumental details and observations. J. Geophys. Res. , 112 . D08305, doi:10.1029/2006JD007224 . Fig . 1. TMF water vapor Raman lidar receiver between April 2005 and October 2006. Fig . 2. Four typical simultaneous radiosonde and lidar water vapor profiles. Total water

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Ulrich Löhnert, S. Crewell, O. Krasnov, E. O’Connor, and H. Russchenberg

and lidar observations are first averaged to a common grid (i.e., 30 s in time and 60 m in height) and then supplemented by temperature, pressure, humidity, and wind speed from an operational NWP model to assist with attenuation correction and cloud phase identification. The full details of how the backscatter targets in each radar/lidar pixel are then categorized into a number of different classes are given by Hogan and O’Connor (2004) . Essentially we make use of the fact that the radar is

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Daniela Nowak, Dominique Ruffieux, Judith L. Agnew, and Laurent Vuilleumier

information about the meteorological conditions are important for weather forecasters, climate studies, and aviation control. One of the high priority duties of observers is the description of the evolution of clouds, especially within the planetary boundary layer. However, automatic weather reports are becoming important because human observations are becoming more difficult to organize, especially during nighttime ( Aviolat et al. 1998 ). The cloud amount (sky coverage in octas) can be automatically

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