Fig. 5: Uncertainty and sensitivity analysis. a: The contribution of groundwater obtained by different calibration scenarios.
a UB, UM, US, UYA, and UYE refer to Upper Brahmaputra, Mekong, Salween, Yangtze, and Yellow basins. The boxplot represents the range (the upper and lower range line), the standard deviation (the upper and lower boundary of the box), and the mean value (the red line) of the contribution of groundwater. The boxplots in blue and red backgrounds represent the results of calibration with and without the isotope objective, respectively. b, c The model sensitivities to the contribution of runoff components. The lines represent the envelope curves of the scatter between model performance on streamflow/isotope simulations and the proportion of groundwater/glacier meltwater. Blue and red curves show the performance on discharge and isotope simulations represented by the difference in NSEdis/NSEiso from the best metrics, respectively. The relationships between the model performance and the contribution of groundwater in all five basins are shown in subfigure b, while only the relationships between the model performance and the contribution of glacier meltwater in the three basins with relatively high contribution (>2%) are shown in subfigure c. The dashed lines in subfigure c represent the optimal contribution of glacier melt at which the best glacier simulations are achieved.
