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Belay Demoz, Cyrille Flamant, Tammy Weckwerth, David Whiteman, Keith Evans, Frédéric Fabry, Paolo Di Girolamo, David Miller, Bart Geerts, William Brown, Geary Schwemmer, Bruce Gentry, Wayne Feltz, and Zhien Wang

dimension of the box being parallel to the dryline. In this section, we examine the horizontal variability of the moisture field in the BL as observed by L2 on 22 May 2002 along one of the early east–west survey legs (shown in Fig. 1 ). Horizontal pointing DIAL measurements made in the framework of IHOP_2002 provided the first ever lidar observations of the horizontal structure of the water vapor field in the vicinity of drylines. The two-dimensional horizontal structure of the water vapor field

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

m the temperature profile follows a dry adiabatic lapse rate indicating a well-mixed layer. Just below the subsidence inversion the dewpoint indicates saturation, consistent with the lidar and satellite observations of a thin cloud. Below 300 m the temperature no longer follows the dry adiabatic lapse rate and becomes a few degrees cooler than the air above, representing another cooler, stable layer below. Perhaps the most compelling evidence of the existence of three distinct layers is the wind

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Hélène Chepfer, Gérard Brogniez, Laurent Sauvage, Pierre H. Flamant, Vincent Trouillet, and Jacques Pelon

. Ingram, 1989: CO 2 and climate: A missing feedback? Nature, 341, 132–134. Pelon, J., P. H. Flamant, and M. Meissonnier, 1990: The French airborne backscatter lidar LEANDRE-1: Concept and operation. 15th Int. Laser Radar Conf., Tomsk, USSR, Institute of Atmospheric Optics, 36–39. Platt, C. M. R., 1973: Lidar and radiometric observations of cirrus clouds. J. Atmos. Sci., 30, 1191–1204. ——, 1978: Lidar backscatter

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Brian J. Vanderwende, Julie K. Lundquist, Michael E. Rhodes, Eugene S. Takle, and Samantha L. Irvin

measurements are taken along four cardinal directions at an inclination of 62.5° above the horizon. The lidar beam cycles through those four angles and after a full rotation uses the retrieved radial observations to calculate a vertical profile of wind vectors ( Lundquist et al. 2014b ). For this experiment, the lidar was configured to measure from 40 to 220 m AGL at 20-m increments, as in previous CWEX experiments ( Rhodes and Lundquist 2013 ). In practice, the maximum height of the profile depends on the

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Hristo G. Chipilski, Xuguang Wang, and David B. Parsons

additional period of 6 h. The model configuration described so far serves as a control experiment and is referred to as BASELINE hereafter. Additional data impact experiments were also conducted, in which PECAN observations from IOP20 were assimilated on the d03 domain. The name of those experiments alongside with optimally tuned 2 localization values for EnKF are summarized in Table 3 . Arguably, the vertical localization value in LIDAR_VAD is relatively large, especially in view of the rapidly

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Sha Lu, Arnold Heemink, Hai Xiang Lin, Arjo Segers, and Guangliang Fu

.1016/0025-5564(85)90098-7 Kawabata , T. , H. Iwai , H. Seko , Y. Shoji , K. Saito , S. Ishii , and K. Mizutani , 2014 : Cloud-resolving 4D-Var assimilation of Doppler wind lidar data on a meso-gamma-scale convective system . Mon. Wea. Rev. , 142 , 4484 – 4498 , doi: 10.1175/MWR-D-13-00362.1 . 10.1175/MWR-D-13-00362.1 Lahoz , W. , B. Khattatov , and R. Menard , 2010 : Data Assimilation: Making Sense of Observations . 1st ed. Springer-Verlag, 718 pp., doi: 10.1007/978-3-540-74703-1 . 10

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E. B. Rodgers, R. Mack, and A. F. Hasler

and Allen)in black. The mode Tee in these cases is the Tee mostfrequently observed within the eye wall CDO, definedby the circles representing the inner and outer radii 'of the eye wall (28 and 83 km) that was determined F~G. 7. WB-57F aircraft path for 12 September 1979, comparingstereo (S) with lidar (L) measurements superimposed on a GOESvisible image of Frederic at 2120 GMT.subjectively from the stereo observations. Withinthese black areas, bounded by the two circles, themean height of the

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Gerald M. Heymsfield, Richard Fulton, and James D. Spinhirne

emphasis on interpretations from lidar measurements. The purpose of this paper is to present an analysis of'unique observations from ER-2 overflights for two Midwest severe weather events both which producedFEBRUARY 1991 HEYMSFIELD, FULTON, AND SPINHIRNE 437IR V features: 1 ) a group of severe thunderstorms inArkansas on 7 May 1984 that later transformed intoa linear mesoscale convective system (MCS), and 2)a severe

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Matthias Schindler, Martin Weissmann, Andreas Schäfler, and Gabor Radnoti

the process ( Simmons and Hollingsworth 2002 ; Bauer et al. 2015 ). While satellite data assimilation is indispensable due to its temporal and spatial data coverage, providing the majority of observations that are assimilated every day, in situ observations of diabatically active regions associated with tropical cyclones (TCs) and midlatitudinal frontal systems are quite limited to a few observations provided by buoys and a scarce observation network of radiosondes and adaptively deployed

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Taylor B. Aydell and Craig B. Clements

for close-range observations of the smoke plume. The deployment site was located perpendicular to the estimated fire spread, providing a safe location from which to scan and with a clear and safe exit route in case the fire moved into the valley. PPI scans at an elevation angle of 5.04° were used to observe plume structures and evolution through the collection of radar reflectivity, velocity, and Doppler spectrum width ( Figs. 5a–l ). Vertical wind profiles taken with the Doppler lidar are shown

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