Monitoring and adjusting ground-based weather radar in Europe using TRMM space-borne radar

* Corresponding author: Marco Gabella – [email protected] This research was co-funded by the European Commission as part of contract EVK2-CT-2002-00155 (VOLTAIRE). Abstract – We show how the TRMM Precipitation Radar (TPR) can be used to monitor and adjust Ground-based Radar (GR) data as a function of the distance from the radar site. The analysis is based on the average, linear radar reflectivity in circular rings around the GR site, 2π, as a function of the range from the GR site. The GR/TPR ratio varies for the Cyprus radar on average from 2 dB, at 10 km, to −10 dB at 100 km. The cause of the average departure at the average range is ascribed mainly to the calibration of the GR. The range dependence of GR/TPR is significant and similar in all the investigated cases. This is attributed to the increasing sampling volume of GR with range combined with non-homogeneous beam filling. For example, at longer ranges of GR, the lower part of the volume could be in rain, whereas the upper part of the same pulse is filled with snow, or even without echo.