GPM和CMORPH卫星产品在重庆暴雨过程中的应用评估  

Application evaluation of GPM and CMORPH satellite products during rainstorms in Chongqing

作　　者：何跃 张新科 李强 邓承之 HE Yue;ZHANG Xinke;LI Qiang;DENG Chengzhi(Chongqing Meteorological Observatory,Chongqing 401147,China;Meteorological Bureau of Rongchang District,Chongqing Rongchang 402460,China)

机构地区：[1]重庆市气象台,重庆401147 [2]重庆市荣昌区气象局,重庆荣昌402460

出　　处：《气象研究与应用》2024年第1期64-71,共8页Journal of Meteorological Research and Application

基　　金：中国气象局创新发展专项(CXFZ2022J011);重庆市自然科学基金面上项目(CSTB2022NSCQ-MSX0665)。

摘　　要：基于2020年6月重庆地区连续3次暴雨过程期间地面高时空分辨率加密雨量观测资料,评估GPM(IMERG)和CMORPH两种主流卫星降水产品对重庆暴雨强降水的估测精度。结果表明,IMERG和CMORPH总体上能较好地捕捉到重庆地区暴雨强降水的时间和空间分布特征,但两种卫星产品均表现为高估过程降水量,IMERG的相对误差RB在0.7%~41.6%之间,CMORPH的RB在23.7%~82.8%之间,CMORPH较IMERG高估更为显著。两种卫星产品对雨强小于20mm·h^(-1)的降水估测精度具有显著的系统性误差,表现为低估雨强小于2.0mm·h^(-1)的降水,高估雨强4.0~19.9mm·h^(-1)的降水,且IMERG的估测精度要优于CMORPH。对雨强超过20mm·h^(-1)的极端强降水,两种卫星产品均表现出极大的不稳定性,探测率(POD)和临界成功指数(CSI)均小于0.1,误报率(FAR)均大于0.85,估测能力有限,需要进一步改进算法。Based on the ground-level high-spatiotemporal-resolution encrypted rainfall observation data during three consecutive regional rainstorm processes in Chongqing in June 2020,the estimation accuracies of two mainstream satellite precipitation products,IMERG(GPM)and CMORPH,for heavy rainfall in Chongqing was evaluated.The results show that IMERG and CMORPH can generally capture the temporal and spatial distribution characteristics of heavy rainfall in Chongqing.However,both satellite products overestimate the total precipitation during the rainstorm processes,with the relative error(RB)of IMERG ranging from 0.7%to 41.6%,and the RB of CMORPH ranging from 23.7%to 82.8%,and the overestimation of CMORPH is more significant than that of IMERG.At the same time,the two satellite products have significant systematic errors in the estimation accuracy of precipitation with rainfall intensity less than 20 mm·h^(-1),which is manifested as underestimation of rainfall intensity less than 2.0 mm·h^(-1) and overestimation of rainfall with rainfall intensity of 4.0~19.9 mm·h^(-1),and the estimation accuracy of IMERG is better than that of CMORPH.For extreme precipitation with a rainfall intensity exceeding 20 mm·h^(-1),both satellite products show great instability,the detection rate(POD)and the critical success index(CSI)are less than 0.1,and the false alarm rate(FAR)is greater than 0.85,which means the estimation ability is limited,and further improvement of the algorithm is needed.

关 键 词：暴雨 卫星产品 GPM CMORPH 应用评估 

分 类 号：P426.6[天文地球—大气科学及气象学]