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Volker Wulfmeyer, Hans-Stefan Bauer, Matthias Grzeschik, Andreas Behrendt, Francois Vandenberghe, Edward V. Browell, Syed Ismail, and Richard A. Ferrare

accurate observations with good coverage and resolution are available in the model domain. By means of assimilation of these data, more insight is gained in the sensitivity of the forecast model on initial fields. Several research programs have been initiated for investigating and improving QPF. The Observing System Research and Predictability Experiment (THORPEX), a Global Atmospheric Research Program, is a 10-yr project of the World Weather Research Program (WWRP). Its primary goal is the extension

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Michael C. Coniglio, Glen S. Romine, David D. Turner, and Ryan D. Torn

because they can be left unattended for long periods of time. To explore the use of these systems for severe weather applications, the National Severe Storms Laboratory obtained an Atmospheric Emitted Radiance Interferometer (AERI) to retrieve profiles of temperature and water vapor and a Doppler lidar (DL) to retrieve wind profiles. These profilers are mounted on a trailer—named the Collaborative Lower Atmosphere Mobile Profiling System (CLAMPS)—to allow for targeted observations ( Wagner et al. 2019

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Andrew L. Molthan, Walter A. Petersen, Stephen W. Nesbitt, and David Hudak

and provide additional scattering to remote sensors. Herein, we present a synthesis of observations of a widespread snowfall event on 22 January 2007, observed during the Canadian CloudSat /Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) Validation Project (C3VP). Field campaigns such as C3VP provide important data required to evaluate the assumptions made within the Goddard scheme by measuring particle size distributions and hydrometeor mass content via surface

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Silke Trömel, Alexander V. Ryzhkov, Malte Diederich, Kai Mühlbauer, Stefan Kneifel, Jeffrey Snyder, and Clemens Simmer

observations are mostly restricted to only one measurement device, like ground-based Doppler radar ( Martner 1995 , 1996 ), airborne Doppler radar ( Winstead et al. 2001 ), ground-based Doppler cloud radar ( Kollias et al. 2005 ), lidar ( Wang and Sassen 2006 ; Platt et al. 2002 ), aircraft penetrations, or photographs. Thus, information about the larger-scale spatial distribution of mammatus and their evolution is scarce at best. Available mammatus observations differ with respect to the type of

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F. Ravetta, G. Ancellet, J. Kowol-Santen, R. Wilson, and D. Nedeljkovic

-based observations will provide a good estimate of vertical cross sections through the jet. 3. The OHP dataset a. Ozone lidar measurements Ozone measurements are performed at OHP using a UV DIAL lidar and ECC ozonesondes (electrochemical cells that detect the ozone concentration in a iodine/iodide solution; Ancellet and Beekmann 1997 ). An ECC sonde was launched at 1600 UTC on 4 March showing a well-mixed tropospheric ozone distribution near 50 ppb and a thermal tropopause at 6

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Gerald M. Heymsfield and Richard Fulton

) ABSTRACT Observations of an isolated group of Oklahoma thunderstorms from NASA's high altitude ER-2 aircraft arepresented. These observations include passive radiometric measurements at frequencies in the microwave (92,183 GHz), infrared (10.7 ~m) and visible portion of the spectrum from a perspective above the storm top.Direct measurements of cloud top height were also collected using a pulsed lidar instrument. These remoteobservations are discussed and compared with coincident radar data from the

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Steven A. Ackerman, W. L. Smith, H. E. Revercomb, and J. D. Spinhirne

Aeronautics and Space Administration, Goddard Space Flight Center, Greenbelt, Maryland (Manuscript received 17 February 1989, in final form 12 June 1990) ABSTRACT Lidar and high spectral resolution infrared radiance observations taken on board the ER-2 on 28 October1986 are used to study the radiative properties of cirrus cloud in the 8-12 t~m window region. Measurementsfrom the High-spectral resolution Interferometer Sounder (HIS) indicate that the spectral variation of

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Jean-Jacques Morcrette

(i.e., cloud fraction, cloud-base height, optical thickness, cloud condensed water). Moreover, in these comparisons, the information about these profiles is usually incomplete, so that a thorough assessment is difficult. In the past, a number of in situ measurement campaigns have provided simultaneous observations of some of the cloud–radiation-related parameters over a given location, usually over a rather short period of time. These measurements unfortunately have not been used generally to

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Huaqing Cai, Wen-Chau Lee, Tammy M. Weckwerth, Cyrille Flamant, and Hanne V. Murphey

as surface mesonets, mobile soundings, aircraft in situ measurements (e.g., Ziegler and Hane 1993 ; Hane et al. 1993 , 1997 , 2001 , 2002 ), Doppler lidar ( Parsons et al. 1991 ), and airborne Doppler radar with clear-air capability ( Atkins et al. 1998 ; Weiss and Bluestein 2002 ). Although drylines are favorable places for convection initiation, not every dryline initiates storms. There have been a few hypotheses trying to explain why convection does not initiate even though the dryline

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David A. Rahn, Thomas R. Parish, and David Leon

perturbations display a Bernoulli relationship. Sharp perturbations at the top of the MBL manifested and were fairly stationary near the pronounced MBL height change. Downwind of Point Conception and tied to the near collapse of the MBL, there is transport of continental aerosol that is inferred from the lidar depolarization and in situ UWKA measurements of number concentration. Observations also reveal a deep layer lingering within the Santa Barbara Channel that is not as cool as that north of Point

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