Gamma distribution function as a tool for monthly precipitation generation in the Bashkortostan Republic, Russian Federation

摘要

This article presents the use of a stochastic approach to generate monthly precipitation total at the regional scale. The data of 32 meteorological stations located in the territory of the Bashkortostan Republic were used. To generate precipitation monthly data the gamma distribution function has been selected. To check the accuracy of approximation of the theoretical distribution of data the χ~2-test has been used. To perform a regional scale application, estimated gamma distribution parameters (α and β) have been interpolated using the geostatistical method (kriging) to map the spatial variability. The parametric Fisher's and Student's tests have been used to test the suitability of the regional approach to describe observed data, for the available point stations. The stochastic model based on gamma distribution function shows acceptable results of precipitation generation. Differences between observed and synthetic data could be caused by the particular climate conditions and orography features of the region.