Impact of Different Potential Evaporation Estimation Methods on Runoff Simulation of Weihe River on the Loess Plateau

Abstract

Evapotranspiration is an important part of the surface hydrologicalprocesses, and potential evapotranspiration has an important impact on thesimulation and prediction of the hydrological process. Taking the upper reach ofBeidao Hydrological Station in Weihe River as the study area, this paper drivesthe SWAT model by Penman-Monteith method and E-601 pan potentialevapotranspiration data (PET601), and analyzes parameter sensitivity and modelcalibration, verification and uncertainty. The results show that the values ofpotential evapotranspiration obtained by different methods are quite different,but they all have similar inner-annual distributions. The potentialevapotranspiration of PET601 methods is lower than that of Penman-Monteith. Aftersimulating the runoff process through hydrological model driven by PETP-M andPET601, the results indicate that the simulation accuracy of the two methods isgood. The PET601 method is more suitable for the simulation in Weihe River onLoess Plateau, and the influence of potential evapotranspiration bias onhydrological simulation is significantly weakened due to adjustment of modelparameters. The research results will provide a reference for the management ofregional evapotranspiration in the ecological protection of the Yellow RiverBasin.

Keywords

• potential evapotranspiration;hydrological model;parameter uncertainty;the Loess Plateau