Comparison of Assimilation Experiments Before and After Correction of Weather Radar Reflectivity Data in Numerical Model ARPS

Taking the accurately calibrated PR (Precipitation Radar) equipped with TRMM (Tropical Rainfall Measuring Mission) satellite as the standard reference source, the reflectivity factor deviation of GR (ground radar) is corrected by comparing with the PR observations. Reflectivity factor from the Doppler radar are added directly to the mesoscale model ARPS(The Advanced Regional Prediction System) by its data processing system ADAS(ARPS Data Analysis System) of simulating two rainstorm process around Jiangsu Province. The experiments include: the control experiment, original and corrected reflectivity separately assimilated experiment. The results showed that: (1) reflectivity data assimilation improved the initial moisture field, and the rainfall prediction (rainfall area and precipitation) was more close to observation data; (2) Corrected reflectivity assimilation adjusted initial moisture field and ascending motion (The adjustment effect is mainly reflected in the first 2 to 3 hours), and improved the rainfall area prediction than original reflectivity assimilation.