基于卫星数据的淮河流域干湿分析及效用评估

Analysis of Dry&Wet Based on TRMM Satellite Rainfall Data and Its Utility Assessment in Huaihe River Basin

选取淮河流域为研究区域,以26个地面气象站的降水数据为基础,评估了TRMM 3B42V7型降水数据的精度,并采用上述两种降水数据,借助标准化降水指数研究了多种时间尺度的流域干湿变化,然后将TRMM卫星降水数据计算结果与地面气象站降水数据计算结果进行比较,评估了TRMM卫星降水数据的干湿分析效用。结果表明:1TRMM3B42V7型数据在月尺度上精度较高、可信度高;2在栅格尺度上,地面气象站降水实测数据和TRMM数据计算结果的相关性较好,其中SPI6s的精度最高,回归分析表明SPI1s精度与纬度和高程变化关系显著,其他仅有CSI3与纬度、CSI6与高程、CSI12与高程的回归方程通过了显著性检验;3在区域尺度上,河南、山东、安徽和江苏四省两种数据计算结果的相关性较好,SPI6s的评价精度最高,而山东省SPI6s和SPI6g的一致性较差;4全流域尺度上SPIs和SPIg的一致性较好,其中SPI6s的精度仍为最高。

In this study, the Huaihe River basin was selected as the study area.Firstly, the Tropical Rainfall Measuring Mission 3B42V7 precipitation data set covering the study area was evaluated via the comparisons with the rain-gauged precipitation data.Subsequently, these two precipitation data sets were adopted to drive the SPI model to assess the wet and dry analysis utility with multiple time scales of TRMM satellite rainfall data.The results show that: a) the correlation and precision are very high between TRMM precipitation and site data on month scale;b) the correlation is also very high between TRMM and site precipitation data on grid scale, and the SPI6s has the highest accuracy, regression analysis shows that the accuracy of SPI1s with latitude and elevation changes dramatically, and it is that only the regression equation of CSI3-latitude, CSI6-elevation and CSI12-elevation through a significant test in the others;c)at the regional scale, the calculation result shows that, the correlation of two kinds of data is also very high in Henan, Shandong, Anhui and Jiangsu provinces, SPI6s has the highest accuracy, while the consistency of SPI6g and SPI6s is poor in Shandong Province;d) at the whole watershed,it has the best consistency between SPIs and SPIg,and SPI6s still has the highest accuracy.