TRMM降雨数据在喀斯特地区的适用性分析——以贵州省为例

Applicability analysis of the TRMM precipitation data in Karst region:a case study in Guizhou Province,China

为验证TRMM(Tropical Rainfall Measurement Mission)降雨数据在喀斯特地区的适用性,以贵州省为研究区,利用贵州省19个气象台站1998-2015年的降水数据,在年尺度和月尺度上验证了TRMM卫星降水数据的精度,并在此基础上基于TRMM月降水数据分析了贵州省的降水时空分布特征。结果表明TRMM降水数据基本能反映降水的空间分布及演变过程,年尺度上TRMM降水数据与站点实测降水量相关系数R=0.817,斜率K=0.751,数据精度较高,数值上比站点实测降水量略高。月尺度上TRMM降水数据与站点实测降水量相关系数最高,达到0.927,斜率为0.9127,数值略高于站点实测降水量。分析表明:坡度对TRMM降水数据精度的影响大于高程和坡向,坡度小于10°的精度较高。总体而言,TRMM降水数据在喀斯特地区具有一定精度,但是降水量少或地形起伏大的地区精度相对较低。

In order to verify the applicability of rainfall data of TRMM （Tropical Rainfall Measurement Mission） in karst area, this study takes Guizhou Province as the research area and uses the precipitation record of 19 meteorological stations in Guizhou Province from 1998 to 2015, and on the yearly and month- ly scale the accuracy of precipitation data of TRMM satellite is verified, and the temporal and spatial dis- tribution characteristics of precipitation in Guizhou Province are analyzed based on the monthly precipita- tion data of TRMM . The results show that the TRMM precipitation data can reflect the spatial distribution and evolution of precipitation. On the yearly scale, the correlation coefficient between the TRMM precipi- tation data and the observed data from metrologieal stations is R = 0. 817 and, the slope is K =0. 751. The data accuracy is high, and the TRMM precipitation data value is slightly higher than the observed da- ta form metrological stations. On the monthly scale, the correlation coefficient between TRMM precipitati- on data and site precipitation is 0. 927, which is the highest, and the slope is 0. 9127. The value of former is slightly higher than that of the measured precipitation. In areas with an altitude greater than 1 300 m and a slope less than 10°, TRMM precipitation data is more accurate. The analysis shows that the effect of elevation on the accuracy of TRMM precipitation data is greater than that of slope and aspect. In gener- al, the TRMM precipitation data has a certain accuracy in the karst area, but the accuracy in the area with less precipitation or complex terrain is relatively low.