| 摘 要： |
Reflectivity bias of ground-based weather radar (GR) is a common error source that can lead to biases in quantitative precipitation estimation (QPE). In this study, the Dual-frequency Precipitation Radar onboard the Global Precipitation Measurement Mission Core Observatory (GPM-DPR) is used to correct GR reflectivity bias. The reflectivity bias correction comprehensively considers variations in GR-DPR reflectivity difference associated with radar frequency difference, data matching approach, precipitation type, GR orographic beam blockage, attenuation, and sample size. The criteria to perform a robust GR-DPR comparison are presented. Disdrometer validation, based on eight typical rain events from April to August 2019, demonstrates that GPM-DPR can effectively reduce GR reflectivity bias to +/- 1 dB. For the period from June to August 2021, the reflectivity correction method is applied to 17 operational GRs. The multiradar QPE shows a significant increase in correlation coefficient (from 0.62 to 0.71), and decreases in relative mean bias (from -0.28 to -0.19) and root mean square error (from 3.96 to 3.54 mm) compared to rain gauges. These results confirm that GPM-DPR can effectively correct the reflectivity biases of a GR network and improve multiradar QPE accuracy and consistency. |
在线留言
联系我们
所长信箱