基于泰森多边形法的庆阳市面雨量计算

Surface precipitation calculation of Qingyang area based on Thiessen polygons method

以甘肃省庆阳市为例,利用结合各雨量站点权重的泰森多边形法进行面雨量计算,分别采用AutoCAD 2008软件进行人工网格划分和ArcGIS 9.3程序进行自动网格划分,并与传统的算术平均法进行比较,探讨了雨量站对计算结果的影响、人为划分网格的主观性因素、泰森多边形法的精度问题等。结果表明,与算术平均法相比,基于泰森多边形法的两种网格划分下的面雨量计算结果更接近实际降雨量,雨量站与网格划分都是影响计算结果的重要因素。

Taking an example of Qingyang city, which is a city in the northeast of Gansu Province, we apply Thiessen Polygons method to calculate the surface precipitation by combining the weights of the rainfall site, then use the AutoCAD 2008 software to make artificial meshes and apply the ArcGIS 9. 3 software to make automatic meshes. At the same time, the calculation result of the surface precipita- tion could be compared with the traditional method that calculate the average rainfall value of all rain- fall site. Based on the results of surface precipitation, we make some relevant analysis on this paper, such as considering the results influenced by the numbers of the rainfall site, the human beingg sub- jectivity factors on the aspect of the grid meshing, and the precision of the method. The results of the study show that, the surface precipitation calculation result, which based on the Thiessen Polygon method, is more close to the real rainfall, what＇s more, both the numbers of rainfall sites and grid meshing are the important factor that affects the calculation results.