Research On The Spatial Distribution Of Rainfall And The Relation Between Spot And Area

Terrain is one of the important factors affecting rainfall and its distribution. The study of rainfall changes with elevation and the relationship between spot and area are important for deriving design storm, especially in some area without enough data. It can provide basis for design flood of water conservancy, traffic and municipal engineering.In this paper, taking Huangshan City as example, it use the linear correlation method to study the relationship of rainfall variation with elevation, and focuses on changes of more than 300m elevation. Then, the rainfall contour and topographic map integrated authentication method is used to assess the rationality and reliability of the results of the mathematical analysis.In the second part of this study, the moving average method and Length series comparison method are used to analyze the representation of the eight sites with 46 years long-term observing data. In the third part, it focuses on the 24h and 3d surface rainstorm point conversion coefficient of Huangshan City. The Visual estimation curve-fitting method based on P-Ⅲ surface-shaped curve is used to calculate the statistical parameters (mean value and Cr) of the design point rainfall and design surface rainfall for each basins of Huangshan City. Furthermore, the relationship between rainfall duration and area is plotted, and the variation of them is analyzed.1. the paper statistics elevation and rainfall data of Huangshan City, the hydrology of the site. In this paper, all of the selected data series is more than 30 years, and the statistical data is up to 2013. The distribution of the sites are more evenly, and more reasonable and reliable.2. The relation of rainfall with elevation is analyzed. Based on the Statistical data, the correlation analysis method and the least squares method are used to calculate the correlation between them. The calculation results show that with the increasing of elevation, the rainfall is increasing gradually.3. Using the moving average method and length of series comparison method, Huangshan City 24h and 3d Storm series data were reliability analysed, and the data series in the years between 1973 to 2013 have better representation. On this basis point and data series in the length of 30 years to 40 years as a secondary point correlation analysis. This article will be divided into the Qingyi River Basin, Xin’an River basins and other river basins, The corresponding surface point conversion coefficient of each basin is calculated and the relationship between conversion coefficient and the area, the relationship between conversion coefficient and the rainfall duration is analyzed. The calculation results show that with the increasing of area, the conversion coefficient decreased, and with the increasing of rainfall duration, the conversion coefficient increased.