The GPM Ground Validation ACHIEVE W-band Cloud Radar IPHEx dataset consists of cloud and light precipitation radar observations gathered during the Global Precipitation Measurement (GPM) mission Ground Validation Integrated Precipitation and Hydrology Experiment (IPHEx) Intensive Observing Period (IOP) in North Carolina from May 1 through June 15, 2014. The goal of IPHEx was to evaluate the accuracy of satellite precipitation measurements and use the collected data for hydrology models in the region. The dataset includes data from the ProSensing 95 GHz W-band cloud radar, which is part of the NASA Goddard Space Flight Center (GSFC) Aerosol, Cloud, Humidity, Interactions Exploring and Validating Enterprise (ACHIEVE) ground-based mobile laboratory. The W-band cloud radar is a scanning 95 GHz dual-polarization (horizontal transmission and co- and cross-polar receiving) Doppler radar used for observing liquid and ice clouds and light precipitation. The instrument measures co- and cross-polar reflectivity, radial velocity, Doppler spectrum width, and signal-to-noise ratio. Linear depolarization ratio was derived from the measured parameters. During the IPHEx campaign, the W-Band radar was used exclusively in vertical-pointing mode. The dataset files are available from May 9 through June 14, 2014 in netCDF-3 data format.

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 NASA S-Band Dual Polarimetric (NPOL) Doppler Radar OLYMPEX V2 dataset consists of rain rate, reflectivity, Doppler velocity, and other radar measurements obtained from the NPOL radar during the Global Precipitation Mission (GPM) Olympic Mountains Experiment (OLYMPEX) campaign. NPOL,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 was placed near the ocean on the Olympic Peninsula. Data files are available from November 5, 2015 thru January 15, 2016 in Universal Format (UF), with browse imagery files in PNG format containing corrected radar reflectivity, differential reflectivity, specific differential phase, differential phase, co-polar correlation, and Doppler velocity images.

The GPM Ground Validation Cloud Radar System (CRS) OLYMPEX dataset provides radar reflectivity and Doppler velocity data collected during the Olympic Mountain Experiment (OLYMPEX). This dataset is used to estimate cloud droplet distribution for the storms monitored during the field campaign. The CRS instrument is a 94GHz W-band Doppler radar with a 3mm wavelength. CRS can be deployed as both an airborne instrument onboard NASA’s high-altitude science aircraft, the Earth Resource 2 (ER-2), as well as a ground based radar system. Only the airborne mode was used during OLYMPEX. In addition to reflectivity and Doppler velocity, the data files include aircraft flight information. The CRS was flown on 10 different days between November 10, 2015 and December 10, 2015. Each data file contains one hour of flight measurements during flight in UTC time. Files for this dataset are in netCDF-3 format and readily accessible without the need of specialized software.

The GPM Ground Validation High-Altitude Imaging Wind and Rain Airborne Profiler (HIWRAP) OLYMPEX dataset consists of Doppler velocity and reflectivity profiles collected by the High-Altitude Imaging Wind and Rain Airborne Profiler (HIWRAP) onboard the NASA ER-2 high-altitude research aircraft during the Global Precipitation Measurement mission (GPM) Ground Validation Olympic Mountains Experiment (OLYMPEX). The OLYMPEX field campaign took place between November 2015 and January 2016, with additional ground sampling continuing through February 2016, on the Olympic Peninsula in the Pacific Northwest of the United States. The purpose of the campaign was to provide ground-validation data for the measurements taken by instrumentation aboard the GPM Core Observatory satellite. HIWRAP is a Doppler radar that combines conical scan mode measurements at two different frequency bands (Ka- and Ku-band) and two different incidence angles (30 and 40 degrees) to obtain profiles of wind and rain. These Level 1B HIWRAP data files are available from November 10 through December 12, 2015 in netCDF-3 format.

The GPM Ground Validation Cloud Radar System (CRS) IPHEx data were collected in support of the Global Precipitation Measurement (GPM) mission Integrated Precipitation and Hydrology Experiment (IPHEx) in North Carolina, with an intense study period occurring from May 1, 2014 through June 15, 2014. The goal of IPHEx was to evaluate the accuracy of satellite precipitation measurements and use the collected data for hydrology models in the region. The ER-2 aircraft flew during the IPHEx field campaign to aid in GPM validation. The science instruments, including the CRS, onboard the aircraft acted as a proxy for GPM satellite instruments. The CRS provided high-resolution profiles of reflectivity and Doppler velocity in clouds at aircraft nadir along the flight track. The CRS data are available from May 3, 2014 through June 12, 2014 and files for this dataset are available in netCDF-3 format.

The GPM Ground Validation NOAA X-band dual-Polarimetric radar (NOXP) IPHEx dataset consists of differential reflectivity, differential phase shift, co-polar cross correlation, radial Doppler velocity, spectrum width, signal index, melting layer index, reflectivity, drop size distribution, and rainfall rate observations, as well as other radar parameters, collected by NOXP mobile radar during the GPM Integrated Precipitation and Hydrology Experiment (IPHEx) field campaign. The IPHEx field campaign occurred in the Southern Appalachians, spanning into the Piedmont and Coastal Plain regions of North Carolina. The NOXP radar, operated by the NOAA National Severe Storm Laboratory (NSSL), was positioned in the Pigeon River basin of the Great Smoky Mountains of North Carolina. NOXP data are available in netCDF-3 format for dates between April 21, 2014 through June 15, 2014. The dataset includes weather condition photos taken at the NOXP radar site in JPG format.

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 NASA S-Band Dual Polarimetric (NPOL) Doppler Radar IFloodS dataset was collected from April 30 to June 16, 2013 near Traer, Iowa as part of the Global Precipitation Measurement (GPM) mission Iowa Flood Studies (IFloodS) campaign. Officially the IFloodS campaign ran from May 1 to June 15 but the NPOL Doppler radar was installed and calibrated prior to the start, allowing for the wider period of record. The NPOL radar, 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 and operated nearly continuously during the IFloodS field campaign. It takes accurate volumetric measurements of precipitation including rainfall rate, particle size distributions, water content and precipitation type. The NPOL Doppler Radar IFloodS data is available in Universal Format (UF) with browse images available in PNG file format.

The GPM Ground Validation CAX1 Radar RB5 format OLYMPEX dataset consists of radar parameters, such as radar reflectivity, Doppler velocity, Doppler width, Differential reflectivity, and signal quality index, provided on a 0.4 to 1.0 km spatial resolution within the OLYMPEX field campaign study region in the state of Washington. These data were obtained for the GPM Ground Validation OLYMPEX field campaign by the SELEX Meteor 60DX10 Compact Weather (CAX1) radar. The CAX1 radar was located at the southern tip of Vancouver Island on the Canadian Forces Base (CFB) Esquimalt Albert Head (AHD) military training area. The CAX1 radar was operated by Environment and Climate Change Canada (ECCC) to support the OLYMPEX field campaign. These data are available in RB5 binary and PNG formats from November 13, 2015 to April 20, 2016.