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Min Deng, Gerald G. Mace, Zhien Wang, J.-L. F. Li, and Yali Luo

that this result may not be exactly applicable to other datasets since the definition of lidar–radar regions depends on the sensitivities of instruments used in different projects. For the three-species ice-phase scheme in models, the cloud ice mass is generally contributed by the small particles, given the small size assumption of cloud ice. However, snow and graupel are not equivalent to the median and large modes in observations, respectively. Therefore, they need to be repartitioned with a

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Reinout Boers, S. H. Melfi, and Stephen P. Palm

variations in lapserate above the PBL and sea surface temperature leavingall other parameters fixed. Lapse rate changes with thesynoptic time scale, which is larger than 2 h, while a50-km change in initial position only produces littlechange in trajectory distance and sea surface temperature along the trajectory, so that the effect on themodel calculations is small.4. Observations and calculationsa. Introduction In this section the observations and calculations willbe presented. To simulate the lidar

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Timothy D. Crum, Roland B. Stull, and Edwin W. Eloranta

774 JOURNAL OF CLIMATE AND APPLIED METEOROLOGY VOLUME26Coincident Lidar and Aircraft Observations of Entrainment into Thermals and Mixed Layers TIMOTHY D. CRUM,* ROLAND B. STULL, AND EDWIN W. ELORANTABoundary Layer Research Team, Department of Meteorology, University of Wisconsin, Madison, W133706(Manuscript received 1 July 1986, in final fo,rm 23 December 1986) Coincident observations of the daytime

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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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Timothy J. Beatty, Chris A. Hostetler, and Chester S. Gardner

15MARCH 1992 BEATTY ET AL. 477Lidar Observations of Gravity Waves and Their Spectra near the Mesopause and Stratopause at AreciboTIMOTHY J. BEATTY, CHRIS A. HOSTETLER, AND CHESTER S. GARDNERDepartment of Electrical & Computer Engineering, Everitt Laboratory, Urbana, Illinois(Manuscript received 31 May 1990, in final form 16 July 1991)ABSTRACT The UIUC CEDAR Rayleigh

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Zhiqiang Cui, Zhaoxia Pu, G. David Emmitt, and Steven Greco

brightness shaded for case 1 and case 2 in all experiments. The locations of DAWN lidar wind profile observations in the two cases are also marked during 15 and 20 June 2017, respectively. Specifically, for case 1, the sizes of the model grids are 163 × 147, 196 × 196, 367 × 295, and 661 × 442 in order from the outermost to innermost domains. The intermediate two-level nested domains cover most of the DAWN data collection area, and the innermost domain corresponds to the main area where the mesoscale

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James R. Campbell, Cui Ge, Jun Wang, Ellsworth J. Welton, Anthony Bucholtz, Edward J. Hyer, Elizabeth A. Reid, Boon Ning Chew, Soo-Chin Liew, Santo V. Salinas, Simone Lolli, Kathleen C. Kaku, Peng Lynch, Mastura Mahmud, Maznorizan Mohamad, and Brent N. Holben

satellite and complicating passive ground-based observations. An example of this is shown in Fig. 4 for 26 September, taken from the NASA Moderate Resolution Infrared Spectroradiometer (MODIS; King et al. 2003 ), aboard the Aqua satellite, and the Cloud–Aerosol Lidar with Orthogonal Polarization (CALIOP) instrument aboard the Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations ( CALIPSO ) platform; Winker et al. 2010 ). The two instruments are flown in sequence in the NASA A

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L. P. Riishøjgaard, R. Atlas, and G. D. Emmitt

remains a high priority for the global observing system. Such observations are expected to be especially valuable in situations in which the balance assumptions used for assimilation of satellite sounding data are invalid and in regions where the geostationary wind observations are either poor or missing altogether. A spaceborne Doppler wind lidar (DWL) is one of the candidate systems for providing these data. The measurement principle is based on the fact that the Doppler shift of the return from an

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Andreas Schäfler, Andreas Dörnbrack, Christoph Kiemle, Stephan Rahm, and Martin Wirth

simultaneous and collocated measurements of the atmospheric variables υ h and q . Meteorological towers and airborne or balloonborne in situ observations provide this information at specific locations and along flight trajectories. However, observations covering larger areas and the complete troposphere are only possible with high-flying aircraft equipped with nadir-pointing remote sensing instruments. During recent years, airborne lidar measurements of both wind and water vapor have been performed to

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Martin Weissmann, Andreas Dörnbrack, and James D. Doyle

line that is generated by boundary layer separation resulting from strong downslope winds and lifted aloft by the lee wave circulation ( Doyle et al. 2009 ). Some of the major challenges for T-REX are to observe these subrotor vortices, to estimate the strength of the horizontal vorticity, and to investigate their characteristics. In this study, high-resolution scanning Doppler lidar observations taken during T-REX are analyzed, and a method for deriving tangential velocity V ϕ and vorticity

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