乌苏里江流域TRMM降水数据精度评价与修正

将地面站点观测的降水数据作为基准降水数据,评估汛期热带降雨观测计划(TRMM)降水产品3B42研究型数据(V7)与实时降水数据(RT)的日以及月尺度数据在黑龙江省乌苏里江流域的时空精度。结果表明:在时间尺度上,TRMM 3B42V7与3B42RT的日降水数据与站点降水数据相比,均系统性偏小,且相关性不是很好;相对而言,3B42RT与站点数据的偏差程度较小,相关性较好;月尺度数据与日尺度数据相比,月数据精度均有很大提高,且2种产品数据精度相差不大;在空间尺度上,TRMM 3B42V7和3B42RT都能较好地展现乌苏里江流域降水的空间分布特征。针对评估结果,使用加法和乘法模型对TRMM 3B42V7和3B42RT的月降水数据进行修正。修正后,2种TRMM卫星降水产品的月降水数据精度均有提高,并且加法模型修正效果更好。因此,可选取加法模型修正后的3B42RT月尺度降水数据用于汛期乌苏里江流域的相关水文研究。

Accuracy evaluation and correction methods of TRMM satellite precipitation data in Ussuri River basin

Taking the ground site observation precipitation as the benchmark data,the accuracy of the daily and monthly precipitation product 3B42V7 and 3B42RT of Tropical Rainfall Measuring Mission(TRMM)in flood season in Ussuri River basin,Heilongjiang Province,are evaluated.The results show that on the time scale the TRMM 3B42V7 and 3B42RT daily precipitation data are systematically smaller than the ground site precipitation data,and their correlation coefficients to the site precipitation are not good,in contrast,the deviation degree between 3B42RT and site precipitation is smaller and the correlation coefficient is better than that of 3B42V7;the monthly precipitation data accuracy of the two products have greatly increased,and the gap between the daily data is close;on the spatial scale,both of the TRMM 3B42V7 and 3B42RT satellite precipitation data can commendably reflect the spatial distribution characteristics of precipitation in Ussuri River basin.In view of the evaluation results,the addition and multiplication model are used to amend the two TRMM satellite monthly precipitation data.The correction results show that the monthly precipitation accuracy of the two precipitation data all have increased,and the correction results of addition model is better than multiplication model.Therefore,the 3B42RT monthly precipitation data amended by addition model can be used for the related hydrological research in flood season in Ussuri River basin.