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Vincent Noel and Kenneth Sassen

, therefore, have a strong influence on the global radiative impact of cirrus clouds ( Chepfer et al. 1999 ). In the present study, observations of horizontally oriented ice crystals using a scanning lidar are analyzed. The deviation of the crystals from the horizontal plane is retrieved as a function of cloud altitude by fitting the lidar angle–dependent observations with a Gaussian model of crystal tilt angles. Different fall attitude modes are explained by considering the off-zenith angle linear

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Zhaoyan Liu, Mark Vaughan, David Winker, Chieko Kittaka, Brian Getzewich, Ralph Kuehn, Ali Omar, Kathleen Powell, Charles Trepte, and Chris Hostetler

1. Introduction The Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP), on board the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations ( CALIPSO ) satellite, was launched in April 2006 ( Winker et al. 2007 ), in formation with the CloudSat satellite, as part of the A-Train constellation of satellites ( Stephens et al. 2002 ). The main objectives of the CALIPSO mission are to provide global measurements of cloud and aerosol spatial distributions and optical properties

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Guangyao Dai, Xiaoye Wang, Kangwen Sun, Songhua Wu, Xiaoquan Song, Rongzhong Li, Jiaping Yin, and Xitao Wang

transport process, it is frequently used to combine the CDL and other types of aerosol lidars ( Engelmann et al. 2008 ; Wandinger et al. 2004 ) to accomplish the simultaneous measurements. However, the cost of comprehensive observations with several lidars is expensive. Considering that the intensity of the CDL echo signals can characterize the concentration of atmospheric particles as well, it is worthwhile to perform the retrieval of the aerosol optical properties based on CDL signals. It should be

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H. Chepfer, M. Chiriaco, R. Vautard, and J. Spinhirne

observations are not resolved vertically and hardly detect very thin cloud layers. Lidars provide powerful means of observing high clouds, especially optically thin clouds, which are difficult to detect from passive remote sensing ( Platt 1973 ; Sassen 1991 ; Bissonnette et al. 2001 ; Noel et al. 2006 ; Hart et al. 2005 ). Despite the difficulties generated by low-cloud masks, ground-based lidar studies of these clouds have allowed researchers to gain limited insight into their spatial and seasonal

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R. M. Banta, L. D. Olivier, E. T. Holloway, R. A. Kropfli, B. W. Bartram, R. E. Cupp, and M. J. Post

1328 JOURNAL OF APPLIED METEOROLOGYSmoke-Column Observations from Two Forest FiresUsing Doppler Lidar and Doppler RadarR. M. BANTA, L. D. OLIVlER, E. T. HOLLOWAY, R. A. KROPFLI, B. W. BARTRAM, R. E. CUPP, AND M. J. POST NOAA /ERL Wave Propagation Laboratory, Boulder, Colorado (Manuscript received 28 August 1991, in final form 2 March 1992) To demonstrate the usefulness of active remote-sensing systems in observin~ form fire plume behavior

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Christine L. Haman, Barry Lefer, and Gary A. Morris

surface layer was most often unstable, whereas observations regularly showed near-neutral stratification. The use of modern ground-based remote sensing techniques capable of continuously measuring the diurnal variations of atmospheric layers has grown substantially. A ceilometer system, or small lidar remote sensing device, is very useful not only because it measures continuously, but because it is also reliable and requires little maintenance. Ceilometers are capable of identifying structures present

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Simone Lolli, James R. Campbell, Jasper R. Lewis, Yu Gu, Jared W. Marquis, Boon Ning Chew, Soo-Chin Liew, Santo V. Salinas, and Ellsworth J. Welton

1. Motivation Campbell et al. (2016) isolate top-of-atmosphere (TOA) net cirrus cloud radiative forcing (CRF) properties for a continuous 1-yr, single-layer cloud dataset developed from NASA ground-based Micro-Pulse Lidar Network (MPLNET; ) ( Welton et al. 2001 ; Campbell et al. 2002 ; Lolli et al. 2013 ) observations collected at Greenbelt, Maryland [38.99°N, 76.84°W; 50 m above mean sea level (MSL)]. They estimate that cirrus clouds exert an absolute net

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Odran Sourdeval, Gérard Brogniez, Jacques Pelon, Laurent C.-Labonnote, Philippe Dubuisson, Frédéric Parol, Damien Josset, Anne Garnier, Michaël Faivre, and Andreas Minikin

Pathfinder Satellite Observations (CALIPSO), which carries the Cloud–Aerosol Lidar with Orthogonal Polarization (CALIOP) and the infrared imaging radiometer (IIR), is of great interest to the research on cirrus clouds. Indeed, it has already been shown that infrared measurements are very efficient for retrieval of ice clouds properties, such as optical thickness, cloud-top pressure, and even microphysical properties (e.g., Parol et al. 1991 ). To use these measurements to retrieve such properties, an

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Gijs de Boer, Edwin W. Eloranta, and Matthew D. Shupe

tens of meters thick and the thickest around 1000 m thick on average. The thickest clouds exist during fall and the thinnest during spring. Barrow observations show substantially thicker clouds, on average, than those observed in Eureka. Thirty-minute average lidar cloud optical depths are reviewed in Fig. 5d . These statistics are skewed by the AHSRL’s inability to penetrate deeper than an optical depth of around 5 before suffering from attenuation. As shown in Fig. 4 , a large fraction of these

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Robert J. Conzemius and Evgeni Fedorovich

for comparing the observed evolution of the sheared atmospheric CBL with large-eddy simulation (LES; Moeng and Sullivan 1994 ; Pino et al. 2003 ; Conzemius and Fedorovich 2006a ). The primary goals of the study are twofold. First, we intend to evaluate LES predictions of the sheared CBL growth against lidar observations of CBL depth evolution and compare LES output with radiometer, radar, and radiosonde data to more fully understand the evolution of the mean wind and temperature in the CBL

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