全球降水观测计划IMERG降水产品对中国大陆极端降雨监测能力评估  

Evaluation of GPM IMERG Precipitation Product in Capturing Extreme Precipitation Events over China's Mainland

作　　者：刘若兰 江善虎[1,2] 任立良 卫林勇[1] 王孟浩 陆玉洁 LIU Ruo-lan;JIANG Shan-hu;REN Li-liang;WEI Lin-yong;WANG Meng-hao;LU Yu-jie(College of Hydrology and Water Resources,Hohai University,Nanjing 210098,China;State Key Laboratory of Hydrology-water Resources and Hydraulic Engineering,Hohai University,Nanjing 210098,China)

机构地区：[1]河海大学水文水资源学院,南京210098 [2]河海大学水文水资源与水利工程科学国家重点实验室,南京210098

出　　处：《中国农村水利水电》2021年第4期57-63,共7页China Rural Water and Hydropower

基　　金：“十三五”国家重点研发计划项目(2016YFA0601504);国家自然科学基金(51979069);中央高校基本科研业务费项目(2019B10414)。

摘　　要：全球降水观测计划GPM降水产品IMERG(Integrated Multi-satellitE Retrievals for GPM)作为热带降水观测计划TRMM降水产品TMPA(TRMM Multisatellite Precipitation Analysis)的继任者,提供了覆盖范围更大、时间序列更长、精度和时空分辨率更高的降水数据来源。论文以国内809个气象台站2000-2017年逐日降水作为基准数据,选取极端日降水(R95p)、极端降水总量(R95pTOT)、最大日降水量(Rx1day)、最大5日降水量(Rx5day)和大雨日数(R25mm)5种极端降水指标,评价IMERG V06 Final(IMERG)在中国大陆的极端降水探测能力,并与TMPA 3B42V7(TMPA 3B42)的结果进行对比。结果表明:①总体上,各项极端指标下IMERG对极端降雨监测表现优于TMPA 3B42产品;②IMERG除倾向于低估R95p、高估R95pTOT外,其他极端降水指标偏差均低于TMPA 3B42;③在极端降雨的探测上,两个卫星产品在高海拔和干旱地区的探测精度较低,但IMERG V06的表现较TMPA 3B42更好,可靠性更高;④在极端降水频率的表现上,IMERG的频率分布较TMPA 3B42更接近于实测雨量,但在更高强度降水(>100 mm/d)中均存在低估。As the successor of TMPA,the Global Precipitation Mission(GPM)IMERG(Integrated Multi-satellitE Retrievals for GPM)products provide a source of precipitation data with greater coverage,longer time series,and higher accuracy and spatial and temporal resolution.Based on gauging daily rainfall from 824 meteorological stations,this paper adopts five extreme precipitation indices(R95p,R95pTOT,Rx1day,Rx5day and R25mm)and three statistical metrics(CC,Bias and rRMSE)to evaluate the extreme precipitation detection capability of IMERG Final product(hereafter IMERG)and compare with the results of TMPA 3B42V7 product(hereafter TMPA 3B42).The result shows that:①The accuracy of IMERG generally outperforms TMPA 3B42 product with higher CC values and lower rRMSE values of each extreme rainfall indices.②Except for the underestimation of IMERG in R95p,both IMERG and TMPA 3B42 estimates show overestimation on all five extreme rainfall indices.③In extreme rainfall detection,the accuracy of the two satellite products has decreased under complex topography conditions,but IMERG exhibits smaller range and lower level of bias than that of TMPA 3B42.④For analyzing the frequency distribution of precipitation with different intensities,the distribution of IMERG is more consistent with gauge precipitation compared to that of TMPA 3B42,but there is underestimation at higher rainfall intensity(>150 mm/d)in both IMERG and TMPA 3B42.

关 键 词：极端降水 频率分布 监测评估 TMPA IMERG 

分 类 号：TV21[水利工程—水文学及水资源]