Simulation of Runoff through Improved Precipitation: The Case of Yamzho Yumco Lake in the Tibetan Plateau

Alpine lakes on the Tibetan Plateau have significantly changed under a changing climate over past decades. However, patterns of inflow sources lakes, i.e., rainfall and melt water snow glaciers, their response to change remain uncertain because obtaining accurate precipitation discharge is difficult due complex topography, spatial variability, scarce stations alpine area. A distributed hydrological model, J2000, was employed in this study simulate runoff component variations Yamzho Yumco Lake glaciated basin during 1974–2019. Except for observed daily from two tributaries, High Asia Refined (HAR) high-resolution reanalysis data combined with field gradient observation cover area validation, all performed simultaneously reduce uncertainty components model. Results showed that average into lake 1974–2019 5.5 ± 1.4 × 108 m3/10a, whereas runoff, glacier snowmelt baseflow contributed 54.6%, 10.8%, 1.8%, 32.7% total mean, respectively. Seasonal spring, summer, autumn, winter accounted 6.7%, 60.6%, 23.9% 8.8% annual In glacial areas, reduction after removing trend times than temperature, non-glacial 1.6 increase temperature trend. The proportion increased at rate 1.0%/10a, decreased 0.07%/10a period.