Introduction to a radar mosaicking system for quantitative precipitation estimation based on the S-band and X-band phase-array polarimetric radars in Shenzhen

Local heavy precipitation caused by severe convection often results in urban waterlogging, causing catastrophic economic losses and hampering people's life and property security. To strengthen the warning ability for urban waterlogging and improve the accuracy of forecasting for urban waterlogging as well as spatial resolution of urban waterlogging risk products, it is imperative to develop high-accuracy and high spatiotemporal resolution precipitation surveillance product. In this paper, we introduce the Shenzhen quantitative precipitation estimation (QPE) mosaicking system with the observations of one S-band polarimetric radar and two X-band polarimetric phase-array radars in Shenzhen. This system comprises 4 modules: (1) non-meteorological echo identi-fication and removal; (2) calculation of hybrid tilt; (3) estimation of rain rate with single radar observations; and (4) mosaicking of rain rate for multi radars. Using the system described in this paper, new QPE products with temporal resolution of 1 min and spatial resolution of 30 m can be generated. The quality of the new QPE product is evaluated against observations of rain gauges and compared with operational QPE product. Results suggest the new QPE product is better than the operational QPE product. It provides more accurate and stable precipitation estimation result.