GROUND VALIDATION OF TRMM/PR MEASUREMENTS

In order to secure the quality of precipitation estimates, ground validation (GV) of satellite data and retrieval algorithms is essential. Since end-to-end comparisons between instantaneous precipitation data observed by satellite and ground-based instruments is not enough to improve the algorithms. The error of various physical parameters in the precipitation retrieval algorithms (e.g. attenuation factor, drop size distribution, terminal velocity, density of the snow particles, etc.) will be estimated by the comparison with the ground-based observation data. The detail of the ground validation observation network in Okinawa for TRMM/PR and GPM/DPR are described. The intensive field observations are conducted using this observation network. Comparisons between the radar reflectivity from the TRMM/PR (2A25) and COBRA and the k-Z relationship estimation by use of the 400MHz WPR are conducted