Large decrease in streamflow and sediment load of Qinghai-Tibetan Plateau driven by future climate change: A case study in Lhasa River Basin

The Qinghai-Tibetan Plateau (QTP) is one of the most sensitive areas to climate change, and fully understanding the impacts of climate on the hydrological process in this region is desired. This study explores the impacts of climate change on the hydrological processes of the Lhasa River Basin (LRB) in QTP based on the Soil and Water Assessment Tool (SWAT). The model is fed with bias-corrected future climatic data derived from three global circulation models (ACCESS1.3, MRI-CGCM3, and MPI-ESM-MR) under two emission scenarios (RCPs 4.5 and 8.5) within two periods (mid-century and end-century). The results indicate that the sediment load and streamflow of LRB would significantly decrease, and the reduction of former is consistently higher than the that of latter in all scenarios and periods. Changes in streamflow and sediment load are mainly caused by temperature increase. The findings provide additional insights into the impacts of climate change on the hydrologic processes of typical basins in QTP and assist decision-makers in developing watershed management plans.