GPM Ground Validation NOAA UHF 449 Profiler MC3E
GPM Ground Validation NOAA UHF 449 Profiler Raw Data SPC format MC3E
Table of Contents
Introduction
The NOAA Ultra High Frequency 449 Profiler data were collected during the NASA supported MC3E campaign in Oklahoma April-June 2011. The UHF 449 MHz profiler was deployed at the DOE Atmospheric Radiation Mission (ARM) Southern Great Plains (SGP) Central Facility. The 449 MHz profiler was one of three NOAA deployed instruments which also included a Parsivel and a 2.8 GHz profiler (S-Band). The 449-MHz profiler operated in one mode and continuously observed in the vertical direction taking approximately 45 seconds to collect one profile of Doppler velocity spectra. Further details are available in the UHF MC3E Data Description document.
The UHF 449 MHz profiler dataset contains both the raw netCDF data files and the processed vertical air motion estimate (omega) at the original 40 second resolution and at 1 minute interpolated resolution. The raw 449 MHz profiler data consists of uncalibrated Doppler velocity spectra data in units of relative power return and provides estimates of the vertical air motion during precipitation from near the surface to just below the freezing level. The raw netCDF data is an exact numerical representation of the raw SPC formatted data. For the proprietary Vaisala SPC format, specialized read software may be purchased from Vaisala.
When the 449 MHz Profiler and the NOAA S-band Profiler raw data files are used together, vertical profiles of raindrop size distributions can be retrieved. Additional details on the S-band 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 NOAA UHF 449 MHz profiler is a phased-array 1/4 scale wind profiler which combines the best sampling attributes of the 404 MHz and 915 MHz profilers. Wind profilers transmit small amounts of energy vertically and slightly off-vertical and then sample the backscatter returns. Coherent integration is done by the profiler, and then those integrations are processed to produce a single Doppler velocity spectrum. The strongest peaks in the spectrum are analyzed to determine those that are the result of atmospheric returns.
Further details on the NOAA UHF 449 MHz profiler are available at http://www.esrl.noaa.gov/psd/data/obs/instruments/WindProfilerDescription.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:
sgpdualfreqomegaC1.<data_level>.yyyymmdd.hhmmss.449mhzsbd.mc3e.tif
[sgp1|sgp]dualfreqomegaC1.<data_level>.yyyymmdd.hhmmss.449mhzsbd.mc3e.nc
sgp449mhzC1.<data_level>.yyyymmdd.hhmmss.lmt_yydddhhmmssa_SM.nc
sgp449mhzC1.<data_level>.yyyymmdd.hhmmss.raw.Hyyddda.SPC.gz
where
sgp = Southern Great Plains
449mhz = 449-MHz Profiler
dualfreqomega = dual-frequency omega
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
SPC = spectra
lm = Lamont, OK
mc3e = Midlatitude Continental Convective Clouds Experiment
nc = netCDF
tif = tagged image file
gz = gzipped
Data Format
The NOAA UHF 449 Profiler dataset is in netCDF format and contains both the raw data files and the processed vertical air motion estimate files. Additionally the NOAA UHF 449 Profiler Raw dataset is available 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 document http://ghrc.nsstc.nasa.gov/uso/ds_docs/gpmgv/mc3e/gpmuhf449mc3e/Profiler_MC3E_Data_Description_2012_08_29v2.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
Ecklund, W.L., D.A. Carter, & B.B. Balsley, "A UHF wind profiler for the boundary layer: brief description and initial results", J. Atmos.Oceanic.Tech., 5, 432-441, 1988.
Rogers, R. R., Ecklund, W. L., Carter, D. A., Gage, K. S., and Ethier, S. A.: 1993, Research Applications of a Boundary-Layer Wind Profiler, Bull. Amer. Meteor. Soc. 74, 567 580.
Martner, B. E., and Coauthors, 1993: An Evaluation of Wind Profiler, RASS, and Microwave Radiometer Performance. Bull. Amer. Meteor. Soc., 74, 599-613.
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/
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