The GPM Ground Validation McGill W-Band Radar GCPEx dataset was collected from February 1, 2012 to February 29, 2012 at the CARE site in Ontario, Canada as a part of the GPM Cold-season Precipitation Experiment (GCPEx). This datset was collected to aid in the achievement of the over arching goal of GCPEx which is to characterize the ability of multi-frequency active and passive microwave sensors to detect and estimate falling snow. The W-Band radar is a single antenna, 94-GHz pulsed Doppler, vertical pointing radar system. Data products from the W-Band radar include radar reflectivity, Doppler moments, and Doppler spectra of variable lengths. The W-Band radar is primarily used to research various cloud properties. The GPM Ground Validation McGill W-Band Radar GCPEx dataset is available in netCDF format.

The GPM Ground Validation Pawnee Radar MC3E dataset was collected by the Pawnee radar data for the Midlatitude Continental Convective Clouds Experiment (MC3E) held in Oklahoma were collected on May 24, 2011 to support the CHILL radar and the NASA ER-2 instrumentation data. The Pawnee is a single polarization (V polarization) Doppler radar. During the ER2 flight, the Pawnee conducted a wide azimuth opening PPI sector volume scan oriented towards the east designed to provide general 3D coverage of the ER2 flight area. When the ER2 reported starting a course reversal, the CHILL and Pawnee radars attempted to start sector scans at the same time to support dual Doppler wind analyses. In an effort to expand the MC3E sampling to a wider geographical area, the NASA ER2 aircraft was directed to Northeastern Colorado while widespread rain was in progress on May 24, 2011. The aircraft flew a series of pre-defined ground tracks that coincided with radials from the CHILL radar. This aided in keeping the aircraft in the plane of a series of RHI scans done by CHILL. The single polarization Pawnee radar maintained volume coverage of the echo system while the radial flight legs were in progress. During aircraft course reversals at the ends of the radial legs, the CHILL and Pawnee radars started volume scans in synchronization to support dual Doppler wind syntheses. CHILL and Pawnee radar data are available as separate datasets.

The GPM Ground Validation KGLD NEXRAD MC3E dataset was collected from April 22, 2011 to June 6, 2011 for the Midlatitude Continental Convective Clouds Experiment (MC3E) which took place in central Oklahoma; however, this dataset contains data from May 18, 2011 to June 6, 2011. MC3E 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. Radar sites include KGLD, KICT, KINX, KTLX, KTWX, KVNX. The Next Generation Weather Radar system (NEXRAD) is comprised of 160 Weather Surveillance Radar-1988 Doppler (WSR-88D) sites throughout the United States and select overseas locations. The GPM Ground Validation NEXRAD MC3E data files are available as tarred binary files.

The GPM Ground Validation Airborne Second Generation Precipitation Radar (APR-2) GCPEx dataset was collected during the GPM Cold-season Precipitation Experiment (GCPEx), which occurred in Ontario, Canada during the winter season of 2011-2012. GCPEx addressed shortcomings in the GPM snowfall retrieval algorithm by collecting microphysical properties, associated remote sensing observations, and coordinated model simulations of precipitating snow. The Second Generation Airborne Precipitation Radar (APR-2) is a dual-frequency (13 GHz and 35 GHz), Doppler, dual-polarization radar system. It has a downward looking antenna that performs cross track scans, covering a swath that is +/- 25 degrees to each side of the aircraft path. Additional features include: simultaneous dual-frequency, matched beam operation at 13.4 and 35.6 GHz (same as GPM Dual-Frequency Precipitation Radar), simultaneous measurement of both like- and cross-polarized signals at both frequencies, Doppler operation, and real-time pulse compression (calibrated reflectivity data can be produced for large areas in the field during flight, if necessary). The APR-2 flew aboard the NASA DC-8 for the GPM Cold-season Precipitation Experiment (GCPEx) from 11 January to 25 February, 2012.

The GPM Ground Validation NOAA UHF 449 Profiler MC3E dataset was collected during the NASA supported Midlatitude Continental Convective Clouds Experiment (MC3E). 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. The Ultra High Frequency 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 raw data files provide estimates of the vertical air motion during precipitation from near the surface to just below the freezing level. Used together with the S-band profiler, vertical profiles of raindrop size distributions can be retrieved. The raw 449MGx profiler data consists of uncalibrated Doppler velocity spectra data in units of relative power return.

The GPM Ground Validation NASA S-band Dual Polarimetric (NPOL) Doppler Radar MC3E dataset was collected by the NASA NPOL radar, which was developed by a research team from Wallops Flight Facility, is a fully transportable and self-contained S-band (10 cm), scanning dual-polarimetric, doppler research radar that collected data nearly continuously during the Midlatitude Continental Convective Clouds Experiment (MC3E) field campaign. 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. NPOL scanned in high resolution Range Height Indicator (RHI) mode (every 40 sec) and provided measurements of precipitation in liquid, mixed and ice phase. The scanning strategy emphasized vertical structure sampling via RHI and narrow sector-volume data collections. Additional files were processed from the UF files using the Colorado State University (CSU) Hydrometeor Identification Algorithm (HID) providing classification of hydrometeors (e.g. rain, drizzle, hail, ice crystals, wet or dry snow, graupel density). Data was collected from April 11, 2011 through June 3, 2011.

The GPM Ground Validation NASA Micro Rain Radar (MRR) MC3E dataset was collected by a Micro Rain Radar (MRR), which is a vertically pointing Doppler radar which provides measurements of vertical velocity, drop size distribution, rainfall rate, attenuation, liquid water content, and reflectivity factor obtained during the Midlatitude Continental Convective Clouds Experiment (MC3E), which took place in Oklahoma during the Spring of 2011. The MRR is a frequency-modulated continuous wave (FMCW) vertically pointing Doppler radar, which operates at 24.24GHz, and is the second generation of the instrument manufactured by METEK (URL: http://metek.de/product/mrr-2/).