A team of scientists from the Northwest Institute of Environment and Resources of the Chinese Academy of Sciences examined changes in the cryosphere across China’s Altai Mountains from 2000 through 2021 and how these shifts influence regional water resources. The findings appeared in the scientific journal CATENA.
The research combined remote sensing, long-term ground-based observations, and field reconnaissance to build a cohesive picture of how the Altai snow and ice have evolved over two decades.
The study shows that glaciers in the Chinese Altai have continued to shrink and thin since 2000, driven by rising temperatures and a complex pattern of snowfall. These trends align with global observations of mountain cryosphere sensitivity to warming and snowfall variability.
In addition, snow depth in the Altai range near the Chinese border increased markedly from 2000 to 2021, while the overall snow-covered area experienced a slight decline. This divergence illustrates the nuanced responses of snowpack to changing weather regimes, with deeper intermittent snowpack coexisting with reduced seasonal coverage.
Permafrost extent in the Chinese Altai also contracted during the study period, signaling a persistent warming signal in high-altitude soils.
When considering the broader hydrological impact, the cryosphere of the Chinese Altai contributed roughly 41.9% to the Irtysh River’s flow. Within that contribution, meltwater from snow cover accounted for about 37.1% of the river level, followed by glacial meltwater at around 3.4%, and permafrost contributing approximately 0.6%. These figures underscore the dominant role of seasonal snowmelt in sustaining downstream water resources while highlighting the smaller but non-negligible inputs from glaciers and permafrost thaw.
Russian scientists have noted a substantial long-term decline in Altai glaciers, with observations indicating that glacier area has roughly halved over the last 150 years. This broader context reinforces the importance of monitoring cryospheric changes for water security in the region and beyond.