Fig. 2: The diagram of detailed water cycle components in the major river basins on the Tibetan Plateau.

The values represent the average of water components across the five basins for the simulation period. Glacier simulations are validated using glacier mass balance data, while snow simulations are validated with snow cover area ratio data, as illustrated in the two subplots on the right. Groundwater simulations are validated using isotope data, as illustrated in the subplot on the left: The surface runoff and groundwater have different isotopic variation, represented by the standard deviation (STD). These two components must be combined in an appropriate proportion to ensure that the isotopic variation of their mixture (i.e., streamflow) matches the observations.