Diagnostic and prognostic modeling of glacier dynamics and the driving factors in the Qilian Mountains, China

Study region Qiyi Glacier in the Qilian Mountains, China. Study focus Glacier flow is one of the important processes in the glacier development and evolution. It provides a scientific basis for assessing glacial disaster risks, and is of great significance for formulating adaptive strategies in response to glacial environmental variations. In this study, a two-dimensional higher-order flow-band glacier flow model (PoLIM) was constructed to analyze the spatio-temporal patterns of surface flow velocity on Qiyi Glacier, and the future dynamics and dominant influencing factors of flow velocity under various climate scenarios were investigated. New hydrological insights for the region Impacted by glacier (ice) volume and thickness, the annual variation in surface flow velocity of Qiyi Glacier exhibits a decreasing trend, declining from 16 m a −1 in 1958–5.97 m a −1 in 2021, with significantly higher flow velocity during the ablation season compared to the non-ablation season. The mean glacier surface flow velocity along the main flowline was 6.92 ± 0.13 m a −1 from 2017 to 2021. Under three future scenarios, this velocity is projected to decrease to 0.71 ± 0.13 m a −1 , 0.73 ± 0.12 m a −1 and 0.47 ± 0.09 m a −1 by 2050, respectively. The spatio-temporal patterns of glacier flow velocity are primarily related to glacier scale (ice thickness) and its variation, with climate warming-induced basal sliding serving as a principal driver of velocity changes in certain part of the glacier.