Understanding the dynamic interplay between floods and climate extremes in the Tibetan Plateau has long been constrained by scale fragmentation. Here, we elucidate the scale-dependent responses using historical observations and modelling. The average flood day and annual maximum daily discharge are governed by two complementary pathways: atmospheric input and catchment modulation. Spatially, flood drivers shift from cryosphere control in the west to monsoon control in the east. Crucially, low-order tributaries are dominated by the atmospheric source mechanism, responding instantaneously to high-intensity precipitation, while catchment modulators play a more important role in high-order mainstems. Furthermore, cross-watershed analysis further underscores that upstream temperature changes contribute 4.0% to downstream flood frequency and 6.4% to magnitude variability via hydrological connectivity. The scale-specific disparities, shaped by the synergistic effects of watershed hydrological processes, underlying surface heterogeneity, climate factor sensitivities, and climate-cryosphere interactions, establish a framework for alpine flood attribution and predictive models. Terrestrial water fluxes on the Tibetan Plateau respond to climate change in uniquely scale-dependent ways shaped by its geography and geomorphology, as shown through analyses of historical observations and modelling.
Li et al. (Wed,) studied this question.