Evaluations of Ground-Based Weather Radars Over the India with the Spaceborne Precipitation Radar

Recently, calibration methods of the ground-based weather radars with reference to spaceborne precipitation radars, such as the Global Precipitation Measurement (GPM) Dual-Frequency Precipitation Radar (DPR), have attracted lot of attention, because of their cost effectiveness and near real-time inputs. This paper describes evaluations for radar reflectivity factors (Z-factors) of S-band and C-band ground-based radars over the Indian region with reference to the GPM/DPR observations. By statistical analyses, using a matching program between the ground-based radar and the GPM/DPR, the S-band ground-based radar measurements at Cherrapunji, Meghalaya, India tended to be significantly underestimated. In this case, a mean bias in the Z-factors was 13.203dBZ was computed. On the other hand, the C-band ground-based radar at Shar, Sriharikota, India was well-corresponded with the GPM/DPR and the mean bias tended to be small (0.688 dBZ).