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Martin Weissmann, Kathrin Folger, and Heiner Lange

uncertainty and contributes up to 70% of the total error. In addition, those errors can be horizontally correlated over several hundred kilometers ( Bormann et al. 2003 ). As a consequence, AMVs are usually thinned rigorously for the assimilation in NWP models. Spaceborne lidars such as the one on the Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations ( CALIPSO ) satellite can accurately determine the height of cloud tops. Therefore, the combination of AMVs with cloud-top information

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Carmen Cordoba-Jabonero, Manuel Gil, Margarita Yela, Marion Maturilli, and Roland Neuber

small, easily handled aerosol lidar from the new generation of micropulse lidars [MPL version 4 (MPL-4), Sigma Space Corporation] at Belgrano Station, Antarctica (78°S, 34°W). Belgrano remains well inside the vortex during wintertime ( Parrondo et al. 2007 ) providing an excellent location for PSC observations. This new equipment will complete the Antarctic program, which INTA is performing continuously from 1994 for stratospheric ozone monitoring and research. Older versions than MPL-4 are already

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Howard B. Bluestein, Jana B. Houser, Michael M. French, Jeffrey C. Snyder, George D. Emmitt, Ivan PopStefanija, Chad Baldi, and Robert T. Bluth

ground-based wind observations in the boundary layer in and near supercells (mostly in the inflow region and just behind the rear-flank gust front), some tornadic, from a very high-spatial resolution, mobile, pulsed Doppler lidar and collocated, mobile, phased-array, X-band Doppler radar data ( Bluestein et al. 2010 ); and 2) to make a case for the use of the lidar for probing the boundary layer of tornadoes. The data were collected during the second year of the Second Verification of the Origins of

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Christian Herold, Dietrich Althausen, Detlef Müller, Matthias Tesche, Patric Seifert, Ronny Engelmann, Cyrille Flamant, Rohini Bhawar, and Paolo Di Girolamo

disappears almost completely due to the advection and mixing of humid air masses into the free troposphere. The lidar observed a different pattern of development for the vertical water vapor distribution. The dry layer persisted until the arrival of the MCS. This observation explains the deviations between the observations and the model at this height range. The advection of moister air masses in the free troposphere forecasted by COSMO-DE is also less dominant in the lidar observations. The dry layer

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Kathrin Folger and Martin Weissmann

assimilation in NWP models and only a small fraction of the available observations is used. Preceding studies ( Velden and Bedka 2009 ; Weissmann et al. 2013 ) demonstrated that AMVs actually represent the wind in a vertically extended layer, although they are traditionally assimilated at discrete levels. In addition, Weissmann et al. (2013) showed that the height of AMVs can be corrected using airborne lidar cloud-top observations. The study presented here further investigates these two approaches that

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Natalie Midzak, John E. Yorks, Jianglong Zhang, Bastiaan van Diedenhoven, Sarah Woods, and Matthew McGill

derived from airborne polarimeter observations. However, only broad plate-like or column-like categories can be derived using polarimeter observations alone. Noel et al. (2004) found lidar depolarization ratio to be sensitive to modeled aspect ratio which allowed for a coarse classification of habit types. Still only broad ice crystal categories including plates or spheroids, irregulars and columns were derived from the study. Also, distinguishing small from large ice crystals is a challenging task

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Minttu Tuononen, Ewan J. O’Connor, Victoria A. Sinclair, and Ville Vakkari

observations at Cabauw in the Netherlands. Sodar data have also been used to determine the occurrence and characteristics of LLJs—for example, in Florida ( Karipot et al. 2009 ) and in Moscow ( Kallistratova and Kouznetsov 2012 ). High-resolution Doppler lidar has proven to be an ideal instrument to measure vertical wind profiles ( Banta et al. 2002 , 2013 ), and Doppler lidar systems have even been deployed on ships ( Tucker et al. 2010 ; Pichugina et al. 2012 ), enabling the investigation of LLJs in

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Irina Strelnikova, Marwa Almowafy, Gerd Baumgarten, Kathrin Baumgarten, Manfred Ern, Michael Gerding, and Franz-Josef Lübken

. 2010 ; Ern et al. 2018 ). On the other hand, different instruments covering different spectral windows of the GW spectrum yield complementary observations. The combination of different instruments, e.g., lidar and satellite, usually provide a more detailed picture of GW parameters ( Llamedo et al. 2019 ). In practice, it is often convenient to have an average reference GW field being representative for a certain latitude and season. Such averaged GW fields, also called climatologies, were

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H. Luce, T. Takai, T. Nakamura, M. Yamamoto, and S. Fukao

acquisition time and the radar resolution volume. Its range resolution (typically 150 m or more) is a limitation because the humidity (and temperature) gradients are frequently shallower. Obviously, colocalized and continuous observations of humidity would more properly help to validate the radar technique approach. This can be achieved from colocalized Raman lidar observations ( Imura et al. 2007 ). Lidar observations can be performed continuously during favorable conditions (clear nights). Humidity is

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Christian Kühnlein, Andreas Dörnbrack, and Martin Weissmann

strong and possibly severe turbulence. However, as already pictured by Förchgott (1949) and impressively shown by Hertenstein and Kuettner (2005) using numerical simulations, a variation of the upstream shear at mountaintop level results in a totally different downslope flow and rotor types. Moreover, observations of downslope flows and rotors revealing the spatial structure in the boundary layer and the temporal evolution were missing. Some ground-based coherent Doppler lidar observations were

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