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Robert Atlas, Ross N. Hoffman, Zaizhong Ma, G. David Emmitt, Sidney A. Wood Jr., Steven Greco, Sara Tucker, Lisa Bucci, Bachir Annane, R. Michael Hardesty, and Shirley Murillo

). The OAWL sensor is described in section 2a . c. Summary of past global OSSEs The basic methodology for OSSEs, as modified by Atlas and others in the early 1980s ( Atlas et al. 1985a ), is illustrated in Fig. 1 . An OSSE begins with an NR generated by a state-of-the-art atmospheric model. From the NR all currently available observations, as well as any new observations to be evaluated, are simulated. In the experiments reported here, for the wind lidar, a very detailed lidar simulation model is

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Shane D. Mayor

observations presented here are unique because 1) they include both in situ and scanning lidar data, 2) the lidar images reveal the microscale structure and motion of the fronts on horizontal and vertical cross sections, and 3) the dataset contains 7 fronts out of the nearly-continuous 77 days of data available. The Raman-shifted Eye-safe Aerosol lidar (REAL; Mayor et al. 2007 ) was deployed in Dixon, California, between 15 March and 11 June 2007 as an appendix to the Canopy Horizontal Array Turbulence

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Tammy M. Weckwerth, Kristy J. Weber, David D. Turner, and Scott M. Spuler

forecasting skill and for obtaining improved accuracy in QPF skill. This latter report noted that “moisture and BL wind field observations are likely to be even more important on the mesoscale.” ( NRC 2012 , p. 87). Optimal temporal resolution requirements for profiling water vapor ranges from better than 1 h for monitoring purposes to better than 1 min for turbulence studies (e.g., Weckwerth et al. 1999 ; Turner et al. 2014 ; Wulfmeyer et al. 2015 ). The differential absorption lidar (DIAL) validated

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Lindsay J. Bennett, Tammy M. Weckwerth, Alan M. Blyth, Bart Geerts, Qun Miao, and Yvette P. Richardson

studies showing horizontal maps of the moisture in the CBL from an airborne water vapor lidar. The structure of the paper is as follows. The layout and description of instrumentation are described in section 2 and the general meteorological situation in section 3 . Observations of the evolution of the early morning boundary layer are presented in section 4 , the development of the convective boundary layer in section 5 , and the characteristics of the open cells in section 6 . A summary of the

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Timothy J. Wagner and Jessica M. Kleiss

observational accuracy of sky cover, it is necessary to compare these observations to a similar instrument with greater vertical range. The micropulse lidar (MPL) is an eye-safe ground-based lidar that operates at 532 nm and is capable of observing cloud-base heights up to 20 km ( Wang and Sassen 2001 ). This instrument provides a dataset of sky cover observations that is qualitatively similar to that of the ceilometer; however, with over 5 times the vertical range, it is capable of observing clouds that

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J. A. Reagan, J. D. Spinhirne, D. M. Byrne, D. W. Thomson, R. G. De Pena, and Y. Mamane

SEPTEMBER 1977 REAGAN ET AL. 911Atmospheric Particulate Properties Inferred from Lidar and SolarRadiometer Observations Compared with Simultaneous In SituAircraft Measurements: A Case StudyJ. A. REAGAN, J. D. SP~NmRNE AND D. M. BYRNE The University of Arizona, Tucson 857fl D. W. THOMSON, R. G. DE PENA AND -. 1VfAMANE The Pennsylvania State University, University Park 16801

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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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David Atlas, Bernard Walter, Shu-Hsien Chou, and P. J. Sheu

(Manuscript received 3 September 1985, in final form 29 January 1986)ABSTRACTThe combination of vertical lidar and in situ meteorological observations from two aircraft provide an unprecedented view of the marine atmospheric boundary layer (MABL) during a cold air outbreak. To a firstapproximation, the lidar reflectivity is associated with the concentration of sea salt aerosols. Across the cappinginversion, the lidar reflectivity contours approximate isentropes and streamlines thereby defining the

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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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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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