A Comparative Study of Doppler Weather Radar and GPM Over Mountainous Terrain In North-East India

Abstract

GPM is one of the crucial satellite radars for rainfall study over the globe and widely being used for several application areas. However, the performance of the same is yet to be understood over orographic regions due to inherent limitations of the Ku/Ka band space borne radars. In this study, we explored a few rainfall events over the complex terrain on Himalayas in North-east India using a ground-based C-band doppler weather radar. The study focused on the representation of the precipitation in terms of rain types which plays a critical role in the Radar QPE. Results indicate a significant underestimation of convective rain by GPM satellite while overestimation of stratiform rain in some cases. The reason could be orographic lifting which may not be well captured at lower levels by the GPM satellite. The study also generated a combined DWR-GPM dataset which could be useful to understand the evolution of rainfall over this location. © 2024 URSI.