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Yann Blanchard
,
Jacques Pelon
,
Edwin W. Eloranta
,
Kenneth P. Moran
,
Julien Delanoë
, and
Geneviève Sèze

present the observations from active instruments (lidar and radar) as well as satellite and surface data. Statistical analyses that are based on independent datasets are summarized in a third section looking to annual, seasonal, and monthly variations of cloud occurrence. On the basis of the coincident data, joint statistics of cloud cover and vertical distribution are given in section 4 . The section also highlights the limits of each observational dataset. We discuss results of the comparisons and

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Richard M. Schotland
,
Kenneth Sassen
, and
Richard Stone

OCXO~ER1971 SCHOTLAND, SASSEN AND STONE 1011Observations by Lidar of Linear Depolarization Ratios for Hydrometeors~RICHARD M. SCHOTLAND, I~ENNETIt SASSEN AND RICHARD STONEDept. of Meteorology and Oceanography, New York University, University Heights (Manuscript received 30 March 1971, in revised form 27 May 1971) ABSTRACT Measurements by monostatic lidar have been performed in the

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Kathrin Folger
and
Martin Weissmann

). Folger and Weissmann (2014) proposed to assign AMVs from Meteosat-9 and Meteosat-10 to vertical layers beneath lidar-derived cloud-top heights. The evaluation of this height reassignment using nearby operational radiosondes resulted in a significant reduction of AMV wind errors. The aim of the present paper is to further elaborate this concept and to overcome the limitations of spatially and temporally rare radiosonde observations by using model equivalents (O-B statistics; see, e.g., Cotton

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Yansen Wang
,
Cheryl L. Klipp
,
Dennis M. Garvey
,
David A. Ligon
,
Chatt C. Williamson
,
Sam S. Chang
,
Rob K. Newsom
, and
Ronald Calhoun

( Taha 1999 ; Brown 2001 ; Martilli et al. 2002 ; Dupont et al. 2004 ). Observational data are a necessity for further improving urban parameterization schemes. Because of the difficulty of obtaining turbulence and wind observations at higher altitude over urban areas, there are, to our knowledge, no reported lidar observations on the LLJ interaction with the urban environment. The recent development of scanning Doppler lidar technologies enables us to observe this type of flow and its interaction

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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; http://mplnet.gsfc.nasa.gov/ ) ( 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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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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Steven D. Miller
,
Courtney E. Weeks
,
Randy G. Bullock
,
John M. Forsythe
,
Paul A. Kucera
,
Barbara G. Brown
,
Cory A. Wolff
,
Philip T. Partain
,
Andrew S. Jones
, and
David B. Johnson

-profile information from the CloudSat ( Stephens et al. 2002 ) and Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations ( CALIPSO ; Winker et al. 2010 ) active sensors is combined with traditional two-dimensional (2D) observations of cloud properties from the Moderate Resolution Imaging Spectroradiometer (MODIS, carried on the Aqua satellite) to provide an ability to evaluate 3D model cloud fields. This evaluation requires innovations to existing MET tools as well as the introduction of new

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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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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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Nicola L. Pounder
,
Robin J. Hogan
,
Tamás Várnai
,
Alessandro Battaglia
, and
Robert F. Cahalan

the receiver FOV ρ and the lidar beam divergence ρ l . We use a variational retrieval scheme ( Rodgers 2000 ) to obtain a best estimate of α at each range gate. The best estimate is obtained by minimizing a cost function, that is the sum of cost functions for observations ( J obs ), prior constraints ( J prior ), and additional constraints ( J constraint ). The observation part of the cost function penalizes the squared difference between the real observations β and the predicted

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