GPM Ground Validation NOAA S-Band Profiler Minute Data MC3E
GPM Ground Validation NOAA S-Band Profiler Original Dwell Data MC3E
GPM Ground Validation NOAA S-Band Profiler Raw Data netCDF format MC3E
GPM Ground Validation NOAA S-Band Profiler Raw Data SPC format MC3E
Table of Contents
Introduction
The NOAA S-Band Profiler data was gathered during the MC3E campaign in Oklahoma April-June 2011. The S-band profiler was deployed at the DOE Atmospheric Radiation Mission (ARM) Southern Great Plains (SGP) Central Facility. Measurements of the vertical structure of precipitation from approximately 200 meters to 16 km were taken as precipitation passed over the profiler site. Further details are available in the Principal Investigator's document ftp://ghrc.nsstc.nasa.gov/pub/doc/gpmgv/mc3e/gpmsbandmc3e/MC3E_NOAA_Sband_Profiler_Description_2012-1209.pdf.
The S-band Profiler Minute Dwell dataset is in netCDF format, and spectra and moment files are included. For the S-band Profiler Original Dwell dataset, the data is in hourly files in netCDF format. The S-band Profiler Raw dataset was saved in two data formats: netCDF and a proprietary Vaisala SPC format. The numeric values in both formats are exactly the same. The raw datasets consist of uncalibrated Doppler velocity spectra data in units of relative power return. For the proprietary Vaisala SPC format, specialized read software may be purchased from Vaisala.
When the S-band Profiler and the NOAA 449 MHz Profiler raw data files are used together, vertical profiles of raindrop size distributions can be retrieved. Additional details on the 449 MHz Profiler Raw dataset are available here.
Campaign
The Midlatitude Continental Convective Clouds Experiment (MC3E) took place in central Oklahoma during the April-June 2011 period. The experiment was a collaborative effort between the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility and the National Aeronautics and Space Administration's (NASA) Global Precipitation Measurement (GPM) mission Ground Validation (GV) program. The field campaign leveraged the unprecedented observing infrastructure currently available in the central United States, combined with an extensive sounding array, remote sensing and in situ aircraft observations, NASA GPM ground validation remote sensors, and new ARM instrumentation purchased with American Recovery and Reinvestment Act funding. The overarching goal was to provide the most complete characterization of convective cloud systems, precipitation, and the environment that has ever been obtained, providing constraints for model cumulus parameterizations and space-based rainfall retrieval algorithms over land that had never before been available.
Further details on GPM MC3E are available at http://gpm.nsstc.nasa.gov/mc3e/. Information on MC3E ARM is available at http://campaign.arm.gov/mc3e/.
Instrument Description
The S-band profiler operates at 2.8 GHz, points vertically, and measures the backscattered power from raindrops and ice particles as precipitating cloud systems pass overhead. The S-band operated in two modes: precipitation mode and attenuated mode. The precipitation mode was the normal or full-power mode, and the attenuated mode was the low-power mode. The profiler alternated between modes collecting either 7 or 9 consecutive precipitation mode profiles separated by 1 attenuated mode profile. Both modes processed radar pulses collected during a 7-second dwell before calculating the Doppler velocity spectra at each radar range gate that were separated by 60-meters in the vertical. The attenuated and precipitation mode data are available in moment, pop spectra (uncalibrated raw spectra) and calibrated spectra hourly files. The S-band spectra were calibrated against the surface disdrometer to determine a radar calibration constant. Calibrated spectra were constructed for each profile and are expressed as reflectivity spectral density. After calibration, the instrument provides an unattenuated reflectivity estimate through the precipitation.
Further details on the NOAA S-band precipitation profiler are available at http://www.esrl.noaa.gov/psd/data/obs/instruments/SbandDescription.html.
Investigators
Christopher R. Williams, Ph.D., PMP
CIRES Research Scientist
University of Colorado at Boulder
Cooperative Institute for Research in Environmental Sciences (CIRES)
Boulder, CO 80309-0216
File Naming Convention
Data and browse files are of the form:
sgp<data_type><mode><data_name>C1.<data_level>.yyyymmdd.hhmmss.mc3e.nc
sgp<data_type><mode><data_name>C1.<data_level>.yyyymmdd.hhmmss.<file_type>.mc3e.tif
sgp<data_type>C1.<data_level>.yyyymmdd.hhmmss.lmc_yydddhhmmss<mode>_SM.nc
sgp<data_type>C1.<data_level>.yyyymmdd.hhmmss.raw.[D|H]lmc0000000<mode>.SPC.tar.gz
where
mode = (precip/P = precipitation, atten/A = attenuated)
sgp = Southern Great Plains
data_type = (sbd = S-band Profiler Original Dwell, 1sbd = S-band Profiler Minute)
C1 = Central Facility
data_level = (00 = raw, a1 = raw counts converted to geophysical units)
yyyymmdd = year, month, day
yyddd = year, day of year
hhmmss = hour, minutes, seconds
data_name = (mom = calibrated moments, spc = calibrated spectra, pop = POP spectra)
SPC = spectra
file_type = (daily, hourly)
lm = Lamont, OK
mc3e = Midlatitude Continental Convective Clouds Experiment
nc = netCDF
tif = tagged image file
tar = Unix "tape archive" format
gz = gzipped
Data Format
The NOAA S-band Profiler Minute Dwell, Original Dwell and Raw datasets are in netCDF format. Addtionally the S-band Profiler Raw dataset was saved in a proprietary Vaisala SPC format. For the Raw dataset, the numeric values in both formats are exactly the same. Specialized read software may be purchased from Vaisala for the SPC format. Further format details are available in the Principal Investigator's document ftp://ghrc.nsstc.nasa.gov/pub/doc/gpmgv/mc3e/gpmsbandmc3e/MC3E_NOAA_Sband_Profiler_Description_2012-1209.pdf.
Citation
Our data sets are provided through the NASA Earth Science Data and Information System (ESDIS) Project and the Global Hydrology Resource Center (GHRC) Distributed Active Archive Center (DAAC). GHRC DAAC is one of NASA's Earth Observing System Data and Information System (EOSDIS) data centers that are part of the ESDIS project. ESDIS data are not copyrighted; however, in the event that you publish our data or results derived by using our data, we request that you include an acknowledgment within the text of the article and a citation on your reference list. Examples for general acknowledgments, data set citation in a reference listing, and crediting online web images and information can be found at: http://ghrc.nsstc.nasa.gov/uso/citation.html
References
White, A. B., J. R. Jordan, B. E. Martner, F. M. Ralph, and B. W. Bartram, 2000: Extending the dynamic range of an S-band radar for cloud and precipitation studies. J. Atmos. Oceanic Technol.,17,1226-1234.
Ecklund, W. L., C. R. Williams, P. E. Johnston, and K. S. Gage, 1999:A 3-GHz profiler for precipitating cloud studies. J. Atmos. Oceanic Technol., 16, 309.322.
Matrosov, S.Y., R. Cifelli, P.C. Kennedy, S.W. Nesbitt, and S.A. Rutledge (2006) A comparative study of rainfall rate retrievals based on specific differential phase shift measurements and X- and S-band radar frequencies. J. Atmos. Oceanic Technol., 23, 952-963.
Contact Information
To order these data or for further information, please contact:
Global Hydrology Resource Center
User Services
320 Sparkman Drive
Huntsville, AL 35805
Phone: 256-961-7932
E-mail: support-ghrc@earthdata.nasa.gov
Web: http://ghrc.nsstc.nasa.gov/
|
