基于网格降水产品的资水流域实况面雨量计算方法研究

Research on Method of Live Surface Rainfall in Zishui Basin Based on Grid Precipitation Products

摘要: 本研究利用2008~2018年中国地面与CMORPH融合逐小时降水网格实况产品与DEM高程数据开展资水流域实况面雨量计算方法研究。首先利用GIS技术对资水流域DEM高程数据进行建模，计算汇流信息并建立栅格河网，进而生成河流分水岭，利用反向搜索技术从流域的出口沿河道向上游搜索每一条河道的集水区范围，对搜到的所有栅格所占区域的边界进行勾画确定总的流域界限，将资水流域划分为6个子流域。其次利用湖南范围降水网格产品，通过GIS技术将降水网格映射到其所属流域范围，建立网格与流域之间的索引。最后利用格点平均法，逐一计算各流域内所有网格点的降雨量平均值，进而得到该流域的流域面雨量实况。

Abstract: This paper uses the hourly precipitation grid live product and DEM elevation data of China ground and CMORPH fusion in 2008-2018 to study the calculation method of the actual surface rainfall in Zishui Basin. Firstly, the GIS technology is used to model the DEM elevation data of the Zishui Basin, calculate the sink information and establish a grid river network, and then generate the river watershed, use the reverse search technology to search the upstream of the river basin from the outlet of the basin. The scope of the water area, the boundary of the area occupied by all the found grids is delineated to determine the total basin boundary, and the water basin is divided into 6 sub-basins. Secondly, using the Hunan-based precipitation grid product, the precipitation grid is mapped to the scope of the watershed by its GIS technology, and the index between the grid and the basin is established. Finally, using the grid point averaging method, the average rainfall value of all grid points in each basin is calculated one by one, and then the basin surface rainfall in the basin is obtained.