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J. W. Wilson, S. B. Trier, D. W. Reif, R. D. Roberts, and T. M. Weckwerth

parameters. The UWKA mostly flew at an elevation of roughly 2.15 km MSL. The primary leg of interest was flown from west to east between 0408 and 0432 UTC. Convection initiation occurred 25 km north of the track at 0405 UTC. Other flight legs helped identify the location of a wind-shift line to be discussed later. Particularly important were Doppler lidar observations from TWOLF and MP3 to help determine vertical wind profiles and cloud base and to detect atmospheric gravity waves. In addition, there was

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Christopher S. Bretherton, Isabel L. McCoy, Johannes Mohrmann, Robert Wood, Virendra Ghate, Andrew Gettelman, Charles G. Bardeen, Bruce A. Albrecht, and Paquita Zuidema

potential cloud-controlling factors, inversion stability and cloud droplet number concentration. Section 6 compares observations from an illustrative CSET flight with reanalysis and a weather-nudged climate model, followed by a summary in section 7 . 2. CSET observations and analysis methods a. Measurements used in this study The G-V instrumentation used for CSET was described in detail by A19 . It included a 94-GHz cloud radar, a high spectral resolution lidar, dropsondes, and in situ probes for

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Kenneth Sassen, Christian J. Grund, James D. Spinhirne, Michael M. Hardesty, and Jose M. Alvarez

of measurement techniques.The lidar sites served as hubs for special rawinsondereleases, radiometric observations, and, when cirruswere present, aircraft operations. Research aircraft fromNCAR filed flight patterns based on the availability ofsatellite and lidar data, and operations in the vicinitiesof the lidar sites were often guided through ground-toair communications. Corresponding author address: Dr. Kenneth Sassen, Det~artmentof Meteorolog% University of Utah, Salt Lake City, UT 84112

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Lisa S. Darby and Gregory S. Poulos

), mesoscale winds, and aircraft turbulence; and 2) qualitatively and quantitatively evaluate mesoscale model results on the observational scale of a lidar. Section 2 provides background information on lee waves and rotors. In section 3 the 1997 MCAT field project is described. The model description appears in section 4 . Section 5 includes weather conditions, observations from the various instruments deployed, and the Regional Atmospheric Modeling System (RAMS) simulation results. Implications for

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Lisa S. Darby, William D. Neff, and Robert M. Banta

visible at the maximum range of the lidar, a second airsonde was prepared and launched just after the mesofront passage at the lidar site. 4. Detailed measurements of mesofront passage a. Premesofront Prior to the mesofront passage, lidar observations concentrated on canyon winds and the horizontal variability of the flow along the foothills. A series of nearly horizontal (0.5° elevation) Doppler lidar scans that began just before 0200 UTC 18 February 1991 showed

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M. Chiriaco, R. Vautard, H. Chepfer, M. Haeffelin, J. Dudhia, Y. Wanherdrick, Y. Morille, and A. Protat

evaluate a microphysical scheme using in situ observations in a few intensive case studies. Nevertheless, a statistical long-term observations approach could also show biases that are more difficult to explain. In this paper, we use remote sensing measurements obtained from the Site Instrumental de Recherche par Télédétection Atmosphérique (SIRTA; http://sirta.lmd.polytechnique.fr ) ground-based atmospheric observatory. Lidar and radar observations taken over 18 months are used for statistical

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M. Chiriaco, H. Chepfer, V. Noel, A. Delaval, M. Haeffelin, P. Dubuisson, and P. Yang

absorption features of ice at two channels located within the atmospheric IR window. It is worth noting that other methods such as those reported by Minnis et al. (1998) , King et al. (2003) , and Platnick et al (2003) are also quite powerful for inferring the microphysical properties of ice clouds. The upcoming Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) mission, scheduled to be launched in 2005, will feature a three-channel (8.7, 10.5, 12 μ m) infrared imager (IIR

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Lisa S. Darby, Robert M. Banta, and Roger A. Pielke Sr.

remainder of this section includes a brief discussion on how topography may influence the sea-breeze flow. Section 2 briefly reviews previous lidar observations of the sea breeze and gives an overview of the Land–Sea Breeze Experiment, with an emphasis on the Doppler lidar measurements. Previous modeling sensitivity studies and a description of the model setup used for the simulations presented in this paper are discussed in section 3 . Section 4 contains model results from 2D simulations with

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Martin D. Weissmann, G. J. Mayr, R. M. Banta, and A. Gohm

(e.g., Banta et al. 1990 , 1996 , 1997 , 1999 ), including downslope windstorm investigations in which hydraulic jump–like structures were revealed ( Banta et al. 1990 ; Clark et al. 1994 ) and MAP studies of gap flow in the Wipp Valley ( Flamant et al. 2002 ; Gohm and Mayr 2004 ; Gohm et al. 2004 ). The present study makes use of the whole dataset of the 2 through 3 October 1999 foehn event. In addition to the lidar observations, in situ measurements from the NOAA P-3 aircraft along Wipp

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Laurent Sauvage, Pierre H. Flamant, Hélène Chepfer, Gérard Brogniez, Vincent Trouillet, Jacques Pelon, and Franck Albers

Monthly Weather Review, Vol. 118, No. 11, 1990 and the Journal of the Atmospheric Sciences, Vol. 52, No. 23, 1995), and the International Cirrus Experiment (ICE’89) in 1989 ( Raschke et al. 1990 ). During the field campaigns in situ probes, passive (i.e., radiometers) and active (i.e., lidars, radars) remote sensors, either airborne or ground based, have been deployed to document different cirrus cloud layers at the mesoscale while satellite data were provided with synoptic-scale observations

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