Application of S-band and X-band Dual Polarization Radar for Quantitative Precipitation Estimation in Shijiazhuang
Based on the observation data of Shijiazhuang S-band radar and X-band radar,along with information from raindrop spectrometer and ground rain gauge data,this investigation analyzes four quantitative precipitation estimation methods:R(ZH),R(ZH,ZDR),R(KDP)and R(KDP,ZDR)applied to two radar systems in Shijiazhuang area.Firstly,the T-matrix method is used to calculate dual polarization parameters using raindrop spectrum data,fitting various rain measurement equations;Subsequently to this,13 precipitation cases are used to test different quantitative precipitation estimation methods,selecting surface rainfall data of Shijiazhuang area.These results reveal that the radar reflectivity factor calculated from raindrop spectrometer data is generally consistent with the radar measurement,with a slight overall overestimation of 5 dB.The precipitation estimation results using R(KDP,ZDR)from both two radars are superior,and the use of polarization parameter KDP can significantly en-hances the rainfall estimation.The addition of ZDR does not substantially improve the rainfall measurement formu-la compared to the single parameter.The application of R(KDP)and R(KDP,ZDR)methods demonstrates height-ened accuracy in precipitation estimation with the X-band radar compared to the S-band radar.The utilization of X-band radar,distinguished by its high spatial-temporal resolution,further refines the precision of urban precipi-tation estimation.