Search Results

You are looking at 101 - 110 of 3,998 items for :

  • Lidar observations x
  • All content x
Clear All
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

Full access
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

Full access
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

Full access
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

Full access
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

Full access
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

Open access
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

Full access
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

Full access
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

Full access
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

Full access