统计降尺度在AREM模式洪水预报试验中应用初探

利用2006~2008年AREM模式预报降雨和漳河水库逐小时雨量站观测降雨及入库流量资料,对水库流域进行网格划分,建立了基于网格的空间分辨率分别为(0.25°×0.25°)和(0.5°×0.5°)的降雨预报统计降尺度模型,同时对降尺度模型了进行了模拟效果的检验,证明该降尺度模型的计算结果可以用于漳河水库洪水预报试验。从2009~2010年中选取了4次洪水过程,进行个例试验,试验结果表明,统计降尺度模型对洪水过程效率系数的改进效果不明显,但对减小预报洪峰流量相对误差有一定的效果,平均相对误差降低了10%左右,峰现时差也略有减小。

PRELIMINARY STUDY ON THE APPLICATION OF STATISTICAL DOWNSCALING IN AREM MODEL FLOOD FORECASTING

Using AREM model of precipitation forecasting, hourly precipitation data of the Zhanghe reservoir station and the reservoir inflow data from the 2006 to 2008, a statistical downscaling model of forecasting precipitation was established based on the grids at the spatial resolutions of 0.25° and 0.5°. At the same time, the simulation result of statistical downscaling model are carried out. The results showed that the proposed method can be used in the flood forecasting of Zhanghe reservoir. From the 2009 to 2010, four prediction experiments were carried out, and the results showed that the statistical downscaling model was not good at improving flood process efficiency, but there was a certain effect to reduce the peak flow forecasting relative error, the average relative error was reduced by about 10%, the peak time error was slightly decreased, too.