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I. Kolev, O. Parvanov, B. Kaprielov, E. Donev, and D. Ivanov

different scanning patterns were used for the lidar observations. Horizontal scanning along six azimuths, 336°, 6°, 30°, 60°, 90°, and 110° with respect to north, as shown in Fig. 1 . Vertical scanning in increments ( θ ° in Fig. 2 ) of 1° between the horizontal and 10° and 2°–5° between 10° and 30°. The vertical scans provide height–range images (HRI) of the vertical cross section of the aerosol backscattering coefficient field along a fixed azimuth φ, as shown in Fig. 2 . The analyses presented

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Katrina S. Virts and John M. Wallace

1. Introduction In the companion paper ( Virts et al. 2010 ; hereafter, VWFA ), we introduce an analysis protocol for relating features in the frequency of occurrence of cirrus clouds in the tropical tropopause transition layer (TTL), as observed by the polar-orbiting Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO), to fields of atmospheric variables throughout the tropics. The protocol involves the generation of a TTL cirrus index (cloud fraction; i.e., the

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S. Mahagammulla Gamage, R. J. Sica, G. Martucci, and A. Haefele

outlook to future work are given in sections 5 and 6 . 2. Measurements and data used in the ERA5-reRH a. RALMO For this study we use Raman lidar measurements from the Raman Lidar for Meteorological Observations (RALMO), located in Payerne (46°48′N, 6°56′E), and operated by MeteoSwiss. RALMO is a fully automated lidar, operating near continuously since 2008, with an average uptime of 50%, with the primary loss of measurements due to events of precipitation and low clouds. The transmitting system of

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Catherine M. Naud, Anthony Del Genio, Gerald G. Mace, Sally Benson, Eugene E. Clothiaux, and Pavlos Kollias

and geographical variations suggest a dependence on environmental state that could result in a contribution to cloud feedback in a climate change. Here, we use ground-based radar and lidar observations in conjunction with information on the state of the atmosphere derived from meteorological reanalyses to investigate the impact of large-scale dynamics and atmospheric state on cloud overlap. Section 2 describes the various datasets used in this study, briefly presents the method, and discusses

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M. Chiriaco, H. Chepfer, V. Noel, M. Haeffelin, and P. Drobinski

advanced methods ( Stubenrauch et al. 1999 ) based on infrared sounders have significantly contributed to improved observations of the vertical structure of the atmosphere in the infrared domain, most observations at these wavelengths do not allow documenting the vertical distribution of crystals in cirrus clouds. The current study explores the potential for coupling data from two lidars to infer the vertical distribution of ice and particles within midlatitude semitransparent cirrus clouds. The first

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Yi Huang, Steven Siems, Michael Manton, Alain Protat, Leon Majewski, and Hanh Nguyen

a ). The CAPRICORN-2016 (Phase I) experiment was conducted with the Australian Marine National Facility (MNF) Research Vessel (R/V) Investigator from 14 March to 16 April 2016. The Investigator was equipped with a suite of state-of-the-art active and passive instruments, making a comprehensive set of measurements including the first-ever concurrent observations on cloud and precipitation with a 95-GHz stabilized cloud radar, a cloud and aerosol backscatter lidar, a micro rain radar, and a

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Micheal Hicks, Ricardo Sakai, and Everette Joseph

detection methods designed for lidar observations. Lidars can continuously monitor the distributions of atmospheric tracers for the detection of ML heights ( Emeis et al. 2008 ). Automatic detection methods are commonly used to attain these heights in a timely manner (e.g., Schmid and Niyogi 2012 ; Granados-Muñoz et al. 2012 ; Luo et al. 2014 ). In general, there are no standard practices for determining ML heights ( Seibert et al. 2000 ) and the approach taken depends on what is being measured (e

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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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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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