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David O'C. Starr, C. Laurence Korb, Geary K. Schwemmer, and Chi Y. Weng

June 1991, in final form 29 April 1992) Airborne observations using a downward-looking, dual-frequency, near-infrared, differential absorption lidar(DIAL) system provide the first measurements of the height-dependent pressure-perturbation field associatedwith a strong mesoscale gravity wave. A pressure-perturbation amplitude of 3.5 mb was measured within thelowest 1.6 km of the atmosphere over a 52.kin flight line. Corresponding vertical displacements of 250-500 mwere inferred from lidar

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C. J. Grund and E. W. Eloranta

-zenith observations. Correlations between small-scale wind structure andcirrus cloud morphology have been observed. These correlations can bias the range averaging inherent in windpwfding lidars of modest vertical resolution, leading to increased measurement errors at drrus altitudes. Extendedperiods of low intensity hackscatter were noted between more strongly organized cirrus cloud activity. Opticalthicknesse/ranging from 0.01-1.4, backscatter-phase functions between 0.02-0.065 sr-~, and backscatter

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Shane D. Mayor, Gregory J. Tripoli, and Edwin W. Eloranta

lidar data to monitor the evolution of convective structures in a convective boundary layer. Avissar et al. (1998) compared autocorrelation functions of lidar backscatter with simulated aerosol scattering in an LES of a homogeneous convective boundary layer. Therefore, this paper builds upon the previous research and demonstrates how techniques that use aerosol backscatter data can be applied to the testing of LESs of inhomogeneous convective boundary layers. 2. Lidar observations The University

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B. B. Demoz, D. O’C. Starr, K. D. Evans, A. R. Lare, D. N. Whiteman, G. Schwemmer, R. A. Ferrare, J. E. M. Goldsmith, and S. E. Bisson

activity during a dryline–frontal merger ( Shapiro et al. 1985 ; Parsons et al. 2000 ). In addition, it is the only lidar-based observational study that clearly illustrates the time–height evolution of the interaction between a dryline, undular bore, and a cold front. This paper focuses only on the observations; numerical simulations and wavelet-based-analysis aspects of the data will follow in a subsequent work. Section 2 describes the synoptic conditions, time series surface mesonet observations

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Robert M. Banta

California, or perhaps even a largercontinental scale. The lidar observations also included the evening transition, which began as a very shallowland breeze observed only by surface observing stations. In the deep sea-breeze layer between 250 m and 1 kmAGL, the flow returned to offshore gradient flow simultaneously through the entire layer 2-4 h after sunset.The sea breeze was thus seen as a daytime interruption of the basic gradient offshore flow.1. Introduction Sea breezes occurring on two different

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Daniel C. Hartung, Jason A. Otkin, Ralph A. Petersen, David D. Turner, and Wayne F. Feltz

Raman lidar is evident ( Figs. 4a–d ). Contrary to the positive impacts on the thermodynamic fields, assimilation of RAM profiles alone degraded the vector wind analysis below 400 hPa in the CONV-RAM case ( Figs. 4e,f ). Minor differences exist below 400 hPa between cases in which DWL wind observations are assimilated, supporting the conclusion from Part I that the improved wind accuracy relative to the CONV case is due to the DWL wind observations. However, as an indirect affect on the wind field

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David H. Levinson and Robert M. Banta

the ASCOTdomain. The NOAA/ERL Environmental Technology Laboratory Doppler lidar, one of an ensemble of instrumentsparticipating in the ASCOT field experiment, obtained high-resolution measurements of the structure of boththe vortex and the canyon drainage flows. The lidar observations documented the kinematic and structuralchanges in the cyclone and their relationship to a drainage jet exiting a nearby canyon. Lidar analyses clearlyshow the layering and stratification present during this case

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Will McCarty, Ronald M. Errico, and Ronald Gelaro

observations of the clouds. For the purpose of this study, the December–February (DJF) months of the nature run are considered, as they correspond to efforts under way at the GMAO that will be the basis for future OSSE studies. 2. Verification data a. CloudSat and CALIPSO The level-2 cloud geometrical profile with lidar product (2B-GEOPROF-lidar; Mace and Zhang 2008 , hereafter CS/CAL) is the primary verification data used in this study. This product contains two-dimensional cloud profiles, vertically

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Alexander Gohm, Günther Zängl, and Georg J. Mayr

1. Introduction The spatial resolution of the present-day numerical weather prediction models has outpaced routine meteorological networks. A thorough verification of the numerical results therefore requires higher-resolution observations that can in general only be collected in dedicated field campaigns. In contrast to in situ measurements, remote sensing instruments such as radar, lidar, sodar, and optical sensors are able to map atmospheric parameters continuously over a wide domain. These

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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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