Two Micro-Pulse Lidar (MPL) systems were deployed to Africa for the SAFARI 2000 Dry Season 2000 experiment. One MPL was set up in Mongu, Zambia, and the other was set up in Skukuza, South Africa. The primary focus of MPL work during SAFARI was to study the vertical distribution and optical properties of smoke from biomass burning in the region.
The MPL system is a single-channel (523nm), autonomous, eye-safe lidar originally developed at GSFC that is now available commercially. The MPL system is used to determine the vertical structure of clouds and aerosols in the atmosphere. MPL data are analyzed to produce optical properties such as extinction and optical depth profiles of the clouds and aerosols. The data for the two SAFARI 2000 sites were added to MPL-Net, a global network of micro-pulse lidar (MPL) systems.
The data set companion file contains example data images and more information about the MPL system, data processing, and data quality [http://daac.ornl.gov/daacdata/safari2k/atmospheric/micro_pulse_lidar/comp/mpl_doc_20040325.pdf ]. Additional information can also be found at: http://mplnet.gsfc.nasa.gov/
Cite this data set as follows:
Welton, J., J. Spinhirne, and J. Campbell. 2004. SAFARI 2000 Micro-Pulse Lidar Cloud and Aerosol Data, Dry Season 2000. Data set. Available on-line [http://www.daac.ornl.gov] from Oak Ridge National Laboratory Distributed Active Archive Center, Oak Ridge, Tennessee, U.S.A. doi:10.3334/ORNLDAAC/715.
Welton, E. J., and J. R. Campbell. Micro-pulse Lidar Signals: Uncertainty Analysis. J. Atmos. Oceanic Technol., accepted, 2002.
Campbell, J. R., D. L. Hlavka, E. J. Welton, C. J. Flynn, D. D. Turner, J. D. Spinhirne, V. S. Scott, and I. H. Hwang. 2002. Full-time, Eye-Safe Cloud and Aerosol Lidar Observation at Atmospheric Radiation Measurement Program Sites: Instrument and Data Processing. J. Atmos. Oceanic Technol. 19: 431-442.
Welton, E. J., J. R. Campbell, T. A. Berkoff, J. D. Spinhirne, S. Tsay, and B. Holben. First Annual Report: The Micro-pulse Lidar Worldwide Observational Network, Project Report. 2001. (Download PDF File)
Spinhirne, J. D. 1993. Micro Pulse Lidar IEEE Transactions on Geoscience and Remote Sensing 31: 48-55.
Schmid, B., J. Redemann, P. B. Russell, P. V. Hobbs, D. L. Hlavka, M. J. McGill, B. N. Holben, E. J. Welton, J. Campbell, O. Torres, R. A. Kahn, D. J. Diner, M. C. Helmlinger, D. A. Chu, C. Robles Gonzalez, and G. de Leeuw. Coordinated airborne, spaceborne, and ground-based measurements of massive, thick, aerosol layers during the dry season in Southern Africa. J. Geophys. Res., accepted, 2002.
Campbell, J. R., E. J. Welton, J. D. Spinhirne, Q. Ji, S. Tsay, S. J. Piketh, M. Barenbrug, and B. N. Holben. Lidar Observations of Tropospheric Aerosols Over Northeastern South Africa During the ARREX and SAFARI-2000 Dry Season Experiments. J. Geophys. Res., in review, 2002.
McGill, M. J., D. L. Hlavka, W. D. Hart, E. J. Welton, and J. R. Campbell. Airborne Lidar Measurements of Aerosol Optical Properties During SAFARI-2000. J. Geophys. Res., in review, 2002.
Welton, E. J., J. R. Campbell, J. D. Spinhirne, and V. S. Scott. Global monitoring of clouds and aerosols using a network of micro-pulse lidar systems. 2001. In Lidar Remote Sensing for Industry and Environmental Monitoring, U. N. Singh, T. Itabe, N. Sugimoto, (eds.), Proc. SPIE, 4153, pp. 151-158.
MPL results are provided for Skukuza and Mongu sites. Three files were generated for each site: a file containing aerosol backscatter profiles, a file containing aerosol extinction profiles, and a file containing other parameters such as aerosol top height. The data are Level 1.5a MPLNET products and are real-time data. They are not quality checked nor are they quality assured. More information on data quality and screening is available in the companion file [ link to DAAC mpl_doc_20040325.pdf ]. The data files are in space-delimited ASCII format.
Mirco-Pulse Lidar Data Files
Mongu aerosol backscatter profiles
Mongu aerosol extinction profiles
Mongu aerosol top height, AOT, Extinction-to-backscatter ratio, MPL Calibration Constant, etc.
Skukuza aerosol backscatter profiles
Skukuza aerosol extinction profiles
Skukuza aerosol top height, AOT, Extinction-to-backscatter ratio, MPL Calibration Constant, etc.
Data File Format
Files Ending with _ext.dat
Files ending with _ext.dat contain aerosol extinction (1/km) profiles and their uncertainties. These files are arranged as rows, with the first column containing the header for each row. The first row is altitude (km) above sea level. The follow on rows contain extinction and uncertainty profiles for times coincident with AERONET optical depth observations. The format of the file is:
Altitude_(km) 1.1475 1.2225 1.2975 ...... 232.236588_Extinction_1/km 2.99E-02 3.23E-02 3.48E-02 ...... 232.236588_Extinction_Uncertainty 8.49E-03 8.53E-03 8.47E-03 ......
The altitude increment is 75 m as set by the MPL range resolution. The number in the extinction and uncertainty headers is the Day of Year, and the decimal indicates fraction of day in UTC.
Files Ending with _bks.dat
Files ending with _bks.dat contain aerosol backscatter (1/km*sr) profiles and their uncertainties. These files are arranged exactly as the _ext.txt files, except the data are backscatter and not extinction.
Files Ending with _para.dat
Files ending with _para.dat contain parameters other than aerosol backscatter and extinction. These files are arranged as columns and contain a header row with the following column titles:
Day_of_Year_(UTC) Latitude Longitude AERONET_AOT_523nm_(+-0.01) Extinction-to-Backscatter_(sr) Extinction-to-Backscatter_Uncertainty AERONET_Angstrom_Exponent AERONET_Angstrom_Coeff AERONET_PolyFitCoeff1 AERONET_PolyFitCoeff2 AERONET_PolyFitCoeff3 AERONET_Airmass AERONET_Water MPL_Detector_Temperature_(C)
Day_of_Year_(UTC) is the same format as the other files. Latitude and Longitude are in decimal format.