Welcome to the GPM Ground Validation Portal. This section provides access to ground validation activities supported by NASA's GPM Project and by GPM Partners around the world.
A meeting was recently held at GSFC to address progress and plans for direct validation of TRMM and GPM spaceflight data products by using ground-based measurements from the national networks of operational weather services. These ground-based networks may include weather service radars, rain gauges and stream flow gauges. Presentations described the Next-Generation Quantitative Precipitation Estimation (Q2), the GPM prototype Validation Network, the use of radar assets on Kwajalein Island as a national network resource, and national network resources for validation of GPM snowfall retrieval algorithims and data products.
C3VP Field Campaign
A field campaign/physical validation prototype was recently completed in conjunction with the Canadian CloudSAT/CALIPSO Validation Programme (C3VP). The C3VP campaign made ground-based and aircraft-based measurements of snowfall and other forms of precipitation in the vicinity of the Centre for Atmospheric Research Experiments(CARE), located about 70 km north of Toronto. See the "quick links" below for information about access the C3VP data.
The illustration above illustrates simulated composite radar reflectivity (in dBZ) generated by Wei-Kuo Tao and co-workers from the Weather Research and Forecasting (WRF) model in conjunction with the Goddard Cumulus Ensemble (GCE) model. Note how the model output captures the timing and transition of lake effect snow bands to the synoptic snowfall event that occurred during the period from January 20-22, 2007. The model results will be compared to measurements made by C3VP ground-based and aircraft-based instruments that operated during the same period. Once the validation of the model output is completed, and assuming that there is sufficient fidelity in results, the model output will be used in forward radiative transfer models to simulate GPM Microwave Imager (GMI) radiance and Dual Precipitation Radar (DPR) reflectivity. The GMI and DPR radiances and reflectivities will be used to test the precipitation retrieval algorithms that are now under development for GPM.
