Calibration Assessment of the Distributed Hydrologic Model Using SWAT-CUP

The idea of distributed hydrologic modeling is embedded in the interrelationships of geospatial and hydro-meteorological data and represented by mathematical abstractions. The behavior of each process is controlled by its attributes as well as by its interaction with other processes active in the catchment. Model calibration is the process of estimating model parameters by comparing model predictions to a given set of assumed conditions with observed data under the same circumstances. The Soil Water Assessment Tool-Calibration Uncertainties Program (SWAT-CUP) is a computer model for calibrations of SWAT model is utilized in the study for the simulation of the daily streamflow. For Langat River Basin, the coefficient of determination (R2), Nash–Sutcliffe efficiency (NSE) and PBIAS for the calibration period were found as 0.75, 0.70, and 0.15, respectively, which confirms the satisfactory performance of the model.