Regional Precipitation-Frequency Analysis in Serbia Based on Methods of L-Moment

Precipitation is the main water resource for agronomy. The frequency is one of the most significant characteristics of precipitation. The objectives of this study are (1) to identify the homogenous regions, (2) to determine the probability distribution that fits precipitation the best for each region, (3) to perform regional precipitation-frequency analysis by using L-moment methods, and (4) to derive the return levels for precipitation. In this study, the precipitation data collected from 24 meteorological stations for the period 1965-2013 over Serbia were analyzed. Three distributions [generalized extreme value (GEV), generalized Pareto (GPD), and generalized logistic (GLO)] based on three parameters (scale, shape, and location) are investigated. The L-moment method is applied to determine the parameters. Three independent precipitation regions (R1, R2, and R3) were studied. The homogeneity test indicates that the identified regions are homogenous. To confirm the goodness-of-fit for the selected three probability distributions, the Z-statistics was applied. Based on the obtained results, the GEV distribution best fits the precipitation data in the regions R1 and R2, while the GPD was selected for the region R3.