The paper titled “Scale-Dependent Performance of GR4J and TUW Models Under Gauge and GLOFAS Discharge Data,” authored by Res. Asst. Oğuzhan Murat HALAT, a member of the Civil Engineering Department, has been published within the proceedings of the 8th Bilsel International Gordion Science Research Congress, held on March 27–28, 2026.
The study evaluates the performance of hydrological models across sub-basins with varying drainage areas in the Bartın River Basin. Two widely used conceptual models, GR4J and TUW, were calibrated using two different discharge datasets (DSİ gauge observations and GLOFAS data) and validated with independent data. Meteorological inputs were obtained from ERA5 reanalysis datasets, and model performance was assessed using Nash-Sutcliffe Efficiency (NSE) and Kling-Gupta Efficiency (KGE) metrics.
The results indicate that the TUW model outperforms the GR4J model both at the sub-basin scale and across different discharge datasets. Furthermore, scenarios utilizing GLOFAS data showed higher performance values, highlighting the potential of reanalysis data as an alternative source in basins with limited or missing observations. The findings clearly demonstrate the influence of scale and discharge data selection on hydrological model performance.
The department congratulates Res. Asst. Oğuzhan Murat HALAT on this valuable scientific contribution and wishes him continued success in his academic work.
