An Investigation into the Applicability of the SHUD Model for Streamflow Simulation Based on CMFD Meteorological Data in the Yellow River Source Region

The simulator for hydrological unstructured domains (SHUD) is a cutting-edge, distributed hydrological model based on the finite volume method, representing the next generation of coupled surface–subsurface hydrological simulations. Its applicability in high-altitude, cold regions covered by snow and permafrost, such as the Yellow River source region, necessitates rigorous validation. This study employed the China Meteorological Forcing Dataset (CMFD) to simulate streamflow in the Yellow River source region from 2006 to 2018, comprehensively assessing the suitability of the SHUD model in this area. The SHUD model excels in simulating monthly streamflow in the Yellow River source region, while its performance at the daily scale is comparable to existing models. It demonstrated significantly better performance in the warm season compared to the cold season, particularly in the middle and lower reaches of the region. Distinct seasonal and regional differences were observed in simulation performance across sub-basins. However, the model encounters limitations when simulating the extensively distributed permafrost areas in the upstream region, primarily due to oversimplification of the permafrost thawing and freezing processes, which points the direction for future model improvements. Additionally, the model’s shortcomings in accurately simulating peak streamflow are closely related to uncertainties in calibration strategies and meteorological data inputs. Despite these limitations, the calibrated SHUD model meets the hydrological simulation needs of the Yellow River Source Region across various temporal scales, providing significant scientific reference for hydrological simulation and streamflow prediction in cold regions with snow and permafrost.