Simulation and projection of hydrological processes in Golmud River basin,northern Qinghai-Xizang Plateau
The accurate simulation and projection of hydrological processes are of great significance for the man-agement and protection of water resources in the Qinghai-Xizang Plateau. However,the limited and uneven dis-tribution of national meteorological observation stations brings a great challenge to the accurate simulation of hy-drological processes in plateau areas. Utilizing multi-source precipitation data is an effective means to improve simulation accuracy. In this study,the Golmud River basin in the northern Qinghai-Xizang Plateau was selected as a case study area. The VIC-CAS model was employed using three precipitation products (ERA5,World-Clim,and TPHiPr) to represent the multi-year monthly average precipitation as the background field. The mete-orological forcing data was derived through interpolation of observed data from meteorological stations,enabling simulation and analysis of the runoff process in the Golmud River basin. Additionally,future runoff predictions were made by downscaling CMIP6 climate model data. The results showed that the meteorological forcing data obtained by using the annual average precipitation of ERA5 as covariate and TPS interpolation method has the most effective simulation results,The Nash efficiency coefficient (NSE) were 0.71 and 0.70 in the calibration and validation period. The contribution of glacier meltwater and snow meltwater to annual runoff in Golmud Riv-er basin is about 14.9％ and 32.5％ respectively. From 1971 to 2019,under the background of slow increase of annual precipitation and significant trend of temperature rise,the increase rates of snowmelt runoff and glacier runoff were 0.28×108 m3·(10a)-1 and 0.03×108 m3·(10a)-1,respectively. The annual runoff increased at a rate of 0.54×108 m3·(10a)-1,and the increase of snowmelt runoff contributed more than 50％. Under the SSP2-4.5 and SSP5-8.5 scenarios,the average annual runoff of Golmud River basin from 2025 to 2100 is projected to be 10.92×108 m3 and 11.51×108 m3,with an increase rate of 0.38×108 m3·(10a)-1 and 0.51×108 m3·(10a)-1,respec-tively. Furthermore,it is projected that snowmelt runoff and glacier runoff in the future period will reach their in-flection points in the 2020s and 2030s under both SSP2-4.5 and SSP5-8.5 scenarios,followed by a significant decrease by the end of the 21st century. This study provides valuable insights for simulating runoff in other data-scarce regions of the Qinghai-Xizang Plateau.
hydrological simulationVIC-CASGolmud River basinrunoff projection
万方数据
维普
