Will climate change inevitably disrupt the cryospheric budget dynamics of the Third Pole?

Abstract The global cryosphere is retreating under ongoing climate change. The Third Pole (TP) of the Earth, which serves as a critical water source for two billion people, is also experiencing this decline. However, the interplay between rising temperatures and increasing precipitation in the TP results in complex cryospheric responses, introducing uncertainties in the future budget of TP cryospheric water (including glacier and snow water equivalents and frozen soil moisture). Using a calibrated model that integrated multiple cryospheric-hydrological components and processes, we projected the TP cryospheric water budgets under both low and high climatic forcing scenarios for the period 2021–2100 and assessed the relative impact of temperature and precipitation. Results showed (1) that despite both scenarios involving simultaneous warming and wetting, under low climatic forcing, the total cryospheric budget exhibited positive dynamics (0.017 mm yr −1 with an average of 1.77 mm), primarily driven by increased precipitation. Glacier mass loss gradually declined with the rate of retreat slowing, accompanied by negligible declines in the budget of snow water equivalent and frozen soil moisture. (2) By contrast, high climatic forcing led to negative dynamics in the total cryospheric budget (−0.056 mm yr −1 with an average of −1.08 mm) dominated by warming, with accelerated decreases in the budget of all cryospheric components. These variations were most pronounced in higher-altitude regions, indicating elevation-dependent cryospheric budget dynamics. Overall, our findings present alternative futures for the TP cryosphere, and highlight novel evidence that optimistic cryospheric outcomes may be possible under specific climate scenarios.