Search Results

You are looking at 151 - 160 of 3,998 items for :

  • Lidar observations x
  • All content x
Clear All
William P. Hooper and Jeffrey E. James

2 s and provided excellent spatial and temporal resolution. However, the GPS positions of the Truxton were only recorded every 15 min, and these positions had to be supplemented by visual observations made from the Glorita of the relative azimuth of the Truxton and its approximate range. Since the estimated positions of the Truxton on pass 4 are inaccurate, the data from this pass are not used in this paper. Figure 4 shows a false color image of the lidar data taken on pass 5 where the

Full access
Rod Frehlich

from towers, sodars, radar profilers, and instrumented aircraft essentially produce a spatial sample of the atmosphere along a line defined by the mean wind (or aircraft trajectory). The scanning lidar is the only instrument able to provide high-spatial-resolution observations in a three-dimensional volume, which provides superior statistical accuracy because of the larger number of independent samples of the atmospheric processes. This is very important for atmospheric research of those phenomena

Full access
Chusei Fujiwara, Kazuya Yamashita, Mikio Nakanishi, and Yasushi Fujiyoshi

(e.g., Sinclair 1969 ). A number of invisible, intense, low-level vortices were detected by a research aircraft over boreal forests ( MacPherson and Betts 1997 ), however, suggesting that these phenomena may occur over various types of environments and a wide range of surface conditions ( Hess and Spillane 1990 ). For instance, in the urban area of Oklahoma City, some apparent vertical vortices can be found in the results of the Doppler lidar observations made by Newsom et al. (2005 , see their

Full access
A. Ansmann, I. Mattis, U. Wandinger, F. Wagner, J. Reichardt, and T. Deshler

, apparatus and data evaluation are outlined in detail. In section 3 , the results are discussed. The observational findings are compared with results of several other lidar measurements; data taken with balloonborne optical particle counters at Laramie, Wyoming; airborne in situ and satellite observations [SAGE, Advanced Very High Resolution Radiometer (AVHRR)]; and model calculations. A summary and concluding remarks are given in section 4 . 2. Apparatus and data evaluation The Raman lidar of the GKSS

Full access
Pavel I. Ionov and Andrew K. Mollner

. , and Hao W. M. , 2012 : Direct multiangle solution for poorly stratified atmospheres . Appl. Opt. , 51 , 6139 – 6146 , doi: 10.1364/AO.51.006139 . Müller, D. , Wandinger U. , Althausen D. , and Fiebig M. , 2001 : Comprehensive particle characterization from three-wavelength Raman-lidar observations: Case study . Appl. Opt. , 40 , 4863 – 4869 , doi: 10.1364/AO.40.004863 . Müller, D. , Kolgotin A. , Mattis I. , Petzold A. , and Stohl A. , 2011 : Vertical profiles of

Full access
Maximilien Bolot and Stephan Fueglistaler

1. Introduction A common problem in many fields of atmospheric sciences, here discussed for the parameterization of ice water content and sedimentation flux from lidar observations, is that remote measurements often have to be supplemented with a priori information (henceforth also referred to as ancillary data) to estimate geophysical quantities of interest. This can create a challenge for operations involving statistics on measurements—such as estimating bulk properties for a whole range of

Free access
Kevin S. Repasky, John A. Reagan, Amin R. Nehrir, David S. Hoffman, Michael J. Thomas, John L. Carlsten, Joseph A. Shaw, and Glenn E. Shaw

be seen that the lidar ratios change for data collected during the morning and data collected during the afternoon. The lidar ratio retrieved from the radiometer data collected in the morning (afternoon) for the 532-nm wavelength is S a ,532nm = 61.2 ± 6.7 sr ( S a ,532nm = 49.5 ± 5.3 sr). The lidar ratio retrieved from the radiometer observations in the morning (afternoon) for the 1064-nm wavelength is S a ,1064nm = 44.4 ± 4.6 sr ( S a ,1064nm = 31.6 ± 3.7 sr). The lidar ratios for both

Full access
Susanne Drechsel, Georg J. Mayr, Michel Chong, Martin Weissmann, Andreas Dörnbrack, and Ronald Calhoun

coherent Doppler lidars were operated by the Arizona State University (ASU) and by the Institute of Atmospheric Physics of the German Aerospace Center (DLR), Oberpfaffenhofen, respectively. A proven algorithm for the 3D wind retrieval from multiple Doppler radars was applied to the dual-lidar observations. We chose the Multiple Doppler Synthesis and Continuity Adjustment Technique (MUSCAT) since it provides stable solutions and can be used over complex terrain. A brief description of MUSCAT will be

Full access
Paul J. Neiman, R. M. Hardesty, M. A. Shapiro, and R. E. Cupp

NOVEMBER 1988 NEIMAN ET AL. 2265Doppler Lidar Observations of a Downslope Windstorm PAUL J. NEIMANCooperative Institute for Research in the Environmental Sciences, University of Colorado/NOAA, Boulder, ColoradoR. M. HARDESTY, M. A. SHAPIRO AND R. E. CUPPNOAA/ERL / Wave Propagation Laboratory, Boulder, Colorado(Manuscript received 12 February 1988, in final form 5 May 1988

Full access
Neil P. Lareau

. To this end, the goal of this study is to provide observational statistics and physical descriptions of subcloud and cloud-base water vapor fluxes associated with shallow cumulus convection over land. This work innovates on a previous Doppler lidar study of cloud-base mass fluxes ( Lareau et al. 2018 ; hereafter LZK18 ) by combining the Doppler lidar observations of vertical velocity with Raman lidar observations of the water vapor mixing ratio to probe the statistics and physics of water vapor

Open access