NASA's Global Precipitation Missions (GPM) is designed as a constellation of satellites to measure precipitation with a 3-hour average revisit time over 80% of the globe, and the data will be available to users within 3 hours of observation time. A Ground Validation System (GVS) is an integral part of GPM.
Global Precipitation Radar (GPM) Space and Ground Radar Comparison Software Goals
The GPM GVS Validation Network (VN) compares TRMM satellite data to similar measurements from the national network of operational weather radars. The goal of the VN is to identify and resolve significant discrepancies between the US national network of ground radar observations and satellite observations. The VN is scalable to targeted hydrometeorological assets external to continental US (e.g., Kwajalein and other national networks). The ultimate goal of such comparisons is to understand and resolve the first order variability and bias of precipitation retrievals in different meteorological/hydrological regimes at large scales.
Collection of coincident spacecraft and ground radar data within various climatic regimes for the purpose of precipitation product validation.
The software collects data from the Precipitation Radar instrument flying on the Tropical Rainfall Measuring Mission (TRMM) spacecraft. It also collects ground radar data from the US weather service radars. The software re-samples both data sets to a common grid and generates statistics that compare radar reflectivity and rain rates. The software does the data collection and comparisons on a routine basis. The software is scalable and additional ground radar sites can be added easily.
Scaling to additional ground radar types and locations. Inclusion of satellite microwave data, rain rates, gauge data. Addition of a user interface to the VN database.
Extensive use by international partners for GPM ground validation.