TRMM卫星降水数据在江苏省的适用性评价

Applicability Evaluation of TRMM Satellite Precipitation Data in Jiangsu Province

利用江苏省内167个雨量站点2000—2013年的实测资料,多尺度检验和探讨TRMM卫星降水数据(TRMM 3B42日降水产品、TRMM 3B43月降水产品)在江苏省应用的可行性。在多年平均尺度上,TRMM降水数据和实测降水数据空间分布上均呈现从南向北递减,但TRMM降水值高于实测降水量。在日尺度上,通过降水频率、漏演和空演率、降水分级分别检验了TRMM 3B42降水数据与实测降水数据的吻合程度,连云港市和宿迁市漏演率和空演率均较低,在该两地可用TRMM反演数据较为准确地判别实际情况有无降水;TRMM 3B42数据对小雨测量的相对误差较大,对中雨、大雨、暴雨的相对误差较小。在月尺度上,通过相关性系数和绝对误差的检验,看出TRMM 3B43数据与地面实测数据一致性程度整体较高,其中在徐州、连云港北部相关性最高,在江苏南部、洪泽湖周边相关性略差。在年尺度上,比较了实测降水数据与TRMM降水数据的变差系数,两者呈现较一致的规律,江苏南部年降水量波动小,北部波动大。

According to the measured data of 167 rainfall stations in Jiangsu Province from 2000 to 2013,the feasibility of the application of TRMM satellite precipitation data(TRMM 3B42 daily precipitation products and TRMM 3B43 monthly precipitation products)in Jiangsu Province is tested and discussed at multiple scales.On the multi-year average scale,the spatial distribution of TRMM precipitation data and measured precipitation data are decreasing from south to north,but the precipitation value of TRMM is higher than the measured one.On the daily scale,the coincidence degree between TRMM 3B42 precipitation data and measured precipitation data is tested by precipitation frequency,missing and empty retrieval rates,and precipitation classification.The missing and empty retrieval rates of Lianyungang and Suqian are lower,thus,in the two places,TRMM inversion data are more accurate to distinguish whether there is precipitation in the actual situation.The relative error of TRMM 3B42 data for measuring light rain is relatively large,while it is small for medium rain,heavy rain,and rainstorm.On the monthly scale,it can be seen that the consistency between TRMM 3B43 data and ground data is overall high by examining the correlation coefficient and the absolute error.The correlation coefficient is the highest in Xuzhou and the north of Lianyungang but slightly lower in the south of Jiangsu and surrounding areas of Hongze Lake.On the annual scale,the variation coefficients between the measured precipitation data and the TRMM precipitation data are compared,and they show the same law that the fluctuation of precipitation is small in the south of Jiangsu but large in the north.