TRMM卫星降水数据在黄河源区的适用性研究

Study on the Applicability of TRMM Satellite Precipitation Data Based on Distributed Hydrological Models in the Headwaters of Yellow River Basin

具有较高时空分辨率的卫星降水数据为研究缺乏地面实测站点流域的水文循环过程提供了有力的支撑。以黄河源区为研究对象,在对比分析2002—2015年TRMM 3B42卫星降水数据与站点实测降水数据的基础上,利用VIC分布式水文模型验证了TRMM降水数据在我国资料稀缺的高寒流域径流模拟的适用性。结果表明,TRMM卫星测雨数据与站点实测降水数据在时空分布及变化趋势上有较好的一致性,TRMM数据多年平均相对误差为-7.1%,相关系数达到0.86。根据VIC模型模拟结果可知,TRMM数据与站点实测数据的月尺度模拟效果较好,日尺度模拟效果不佳,丰水年TRMM数据模拟精度较枯水年高。

Satellite precipitation data with high spatial⁃temporal resolution provides a strong support for the study of hydrological processes in watersheds lacking ground stations.In this study,the applicability of satellite precipitation data TRMM 3B42 for streamflow simulation over the source region of the Yellow River from 2002 to 2015 was evaluated by using the VIC distributed hydrological model.The results show that the TRMM satellite precipitation data is consistent with the gauge data in the spatial and temporal distribution and change trend.The annual average bias between the TRMM data and the rain⁃gauge observations precipitation is-7.1%and the correlation coefficient reaches to 0.86.According to the simulation results of the VIC model,the TRMM data show good performance in monthly streamflow simulation.However,it gets poor performance for daily streamflow simulation.The simulation accuracy of the TRMM data in the wet years is higher than that in dry years.