GPM卫星降水产品在长江流域应用的精度估算  

Accuracy evaluation of GPM precipitation product in Yangtze River basin

作　　者：吴一凡 张增信[1] 金秋[1] 黄钰瀚 WU Yifan;ZHANG Zengxin;JIN Qiu;HUANG Yuhan(Collaborative Innovation Center of Sustainable Forestry in Southern China of Jiangsu Province,Nanjing Forestry University,Nanjing 210037,China)

机构地区：[1]南京林业大学江苏省南方现代林业协同创新中心

出　　处：《人民长江》2019年第9期77-85,152,共10页Yangtze River

基　　金：国家自然科学基金项目(41171020);江苏高校优势学科建设工程资助项目(PAPD);卫星海洋环境动力学国家重点实验室开放基金项目

摘　　要：为评价GPM卫星降水产品在长江流域的探测精度,利用长江流域224个气象站点2014年4月1日至2017年12月31日的逐日实测降水数据和GPM卫星遥感探测数据,通过相关系数R、平均绝对误差MAE、均方根误差RMSE、相对偏差RB四种指标评价了GPM卫星降水产品在长江流域年、月、日尺度上的探测精度,并运用探测率POD、误报率FAR、偏差率BIAS、公正先兆评分ETS四种指标衡量了GPM对不同量级降水的捕捉能力。结果表明:①年尺度上,GPM卫星与实测降水的R、MAE、RMSE和RB值分别为0.92,0.44,0.57mm/d和5.68%,表现出较高的探测精度;②月尺度上,GPM卫星在冬夏两季月份与实测值的一致性较差,并明显低估了冬季月份的降水,且对夏季月份的降水估计存在较高误差;③日尺度上,GPM对弱降水的捕捉能力较强,对强降水探测能力较差;④总体而言,GPM在年月尺度上通过表现出较高的相关系数R和较低的MAE和RMSE误差值,显示出比日尺度上更高的探测精度。In order to evaluate the accuracy of the latest-generation Global Precipitation Measurement IMERG(GPM)in the Yangtze River basin,four commonly used error metrics(R,MAE,RMSE,RB)and four category statistical indexes(POD,FAR,ETS,BIAS)were adopted to evaluate the precipitation capture capability of GPM satellite to different precipitation level and the precipitation detecting accuracy of GPM satellite product on annual,monthly and daily scales by comparing with the gauged daily precipitation data obtained from the 224 meteorological stations in the Yangtze River basin during April 2014 to December 2017.Results showed that:①At annual scale,GPM product presented good detection accuracy in the whole Yangtze River basin,the R,RMSE,MAE and RB reached to about 0.92,0.44 mm/d,0.57 mm/d and 5.68%,respectively.②At monthly scale,GPM had a lower consistency in winter and summer months.It significantly underestimated the precipitation in winter months and had greater errors in summer months.③At daily scale,GPM obtained a better capability of detecting weak rainfall events than heavy precipitation.④In general,GPM had a better estimation accuracy at annual and monthly scales by showing a higher correlation coefficient and a lower value of MAE and RMSE compared with the results at daily scales.

关 键 词：GPM卫星产品 降水量 精度评价 长江流域 

分 类 号：P33[天文地球—水文科学]