Author(s): Mohammad Zounemat-Kermani; Sanaz Zeraati
Linked Author(s):
Keywords: Copula function; Peak flow; Qarah-Soo Watershed; Flood; Hydrology
Abstract: Flood is considered as one of the major natural disasters, in which lack of proper management can cause life losses and financial damages. Since many infrastructures such as highways, dams, bridges, and drainage systems are located near the confluence point of tributaries, it is very important to evaluate and estimate peak flow in such areas. Thus, it is possible to estimate the flooding probability by examining a number of floods with specified return periods. In this study, according to the statistical data of annual peak flow between 1979 and 2000 in Qarah-Soo Watershed (located in Kermanshah Province in Iran, ) annual peak flows are estimated using copula models in four types of Archimedean copula functions including: 1) regression form, 2) summation, 3) weight factor, and 4) nearest station as well as conditional copula model. Thereafter, probability distributions were fit to the data series and, finally, the values of annual peak flow were obtained using the best copula function in each model. Results showed that copula function in the form of regression with Spearman's correlation coefficient of 0.872 and determination coefficient of 0.671 had higher accuracy and was superior to other models in terms of estimating annual peak flow.
Year: 2018