Comparative study on spatial variability of rainfall and its spatial interpolation methods

Zhu Li Hao Ganhong

In order to compare the advantages and disadvantages of various spatial interpolation methods in the study of spatial variability of precipitation, taking the Wuding River basin as the research object, the spatial interpolation methods such as inverse distance weighting method, trend surface fitting method, spline interpolation method, ordinary kriging method and universal kriging method were used to interpolate the precipitation in the basin, and the change of spatial field was analyzed. For ordinary kriging method, the results show that the semivariogram of precipitation accords with the general spherical model. Comparing the continuous spatial distribution of various interpolation methods with the actual observation data, the results show that there is no significant difference between several interpolation methods, but the general kriging method and the inverse distance weighting method have the best overall effect, especially the circular model of the general kriging method. Finally, the above interpolation methods are used to interpolate and plot the precipitation in the basin.