Since the 20th century, the temperature on the Qinghai–Tibetan Plateau (QTP) has increased at a rate of 2–3 times that of global warming. Consequently, the soil temperature and active layer thickness have also increased, which have directly caused severe degradation of the frozen ground on the QTP. Using a hydrological model driven by climate and vegetation forcing, the spatial and temporal changes in the hydrothermal characteristics of the Upper Yellow River Basin (UYRB) from 1960 to 2019 were modeled and the mechanism of the changes was analyzed. During the past six decades, the soil temperature in the UYRB exhibited an increasing trend. The degradation of permafrost in the UYRB was accompanied by thickening of the active layer, a reduction of the maximum depth of the seasonal frost penetration, and continuous extension of the basin thawing time. This degradation was also associated with the increase in the soil moisture content and decrease in the soil ice content, resulting in degradation of the permafrost area by one-tenth of the total area in the UYRB. The reduction of the permafrost area and the thickening of the active layer can profoundly impact hydrological processes and ecosystems. These findings play a critical role in designing efficient strategies to manage and protect frozen ground and serve as a valuable reference for understanding the consequences of frozen ground degradation globally.

20世纪以来，青藏高原气温上升速度是全球变暖速度的2-3倍。随之而来的土壤温度和活性层厚度也随之增加，直接导致青藏高原冻土严重退化。利用气候和植被强迫驱动的水文模型，模拟了1960-2019年黄河流域上游水热特征的时空变化，并分析了变化机制。近60年来，青藏高原土壤温度呈上升趋势。青藏高原多年冻土的退化伴随着活动层的增厚、季节性霜冻最大渗透深度的减少以及盆地融化时间的不断延长。这种退化还与土壤含水量的增加和土壤冰含量的减少有关，导致青藏高原多年冻土面积退化了十分之一。永久冻土面积的减少和活动层的增厚可以深刻地影响水文过程和生态系统。这些发现对于设计管理和保护冻土的有效策略发挥着关键作用，并为了解全球冻土退化的后果提供了宝贵的参考。