Climate Change Accelerates River–Lake System Reorganization on the Tibetan Plateau

Climate change is accelerating the reorganization of river–lake systems on the Tibetan Plateau, reshaping hydrological and ecological processes within the region known as the "Asian Water Tower". A new study led by Professor LU Shanlong from the Aerospace Information Research Institute, Chinese Academy of Sciences (AIRCAS), has published in Communications Earth & Environment, reveals that since 2019, when the previously isolated Zonag-Yanhu drainage basin became connected to the headwaters of the Yangtze River, both hydrological and ecological processes within the basin have undergone rapid transformation.

By integrating field investigations, remote sensing, and climate data, the researchers reconstructed nearly four decades of hydrological evolution across the Zonag, Kusai, Haidingno'er, and Yanhu lakes in the Hoh Xil region of the Tibetan Plateau. They found that a 2011 dam breach at Zonag Lake triggered hydrological connectivity among the lakes, while a 2019 artificial drainage project linked Yanhu Lake to Qingshui River — the northernmost tributary of the Yangtze River, thereby establishing a hydrological connection to the river’s northern source.

The study highlights that extreme precipitation events have intensified in recent years, driving sharp lake-level fluctuations and heightening downstream flood risks. In 2024, precipitation in the region rose by 195% above the historical average, widening the outlet breach and increasing discharge from Zonag Lake, which in turn caused the downstream Yanhu Lake to expand once again. Meanwhile, the shoreline of Zonag Lake continued to retreat, exposing sediments that have become new sources of sandstorms. Since 2017, the frequency of sandstorm events in the region has risen significantly, degrading the calving habitats of Tibetan antelopes along the lakeshores.

Looking ahead, projections indicate continued warming and wetter conditions through 2035, suggesting that that hydrological and ecological instability will likely persist. To mitigate these risks, the researchers recommend adaptive management strategies — such as reinforcing the outlet structure of Zonag Lake, stabilizing receding shorelines with gravel, and establishing a long-term monitoring system to prevent secondary breaches, downstream flooding in Yanhu lake, and ecological degradation.

This research advances our understanding of the climate-hydrology-ecology mechanism coupling in high-altitude regions and provides critical guidance for water resource management, disaster prevention, and ecosystem conservation across the Tibetan Plateau and similar alpine regions globally.

Outlet of Zonag Lake-July 17, 2024. (Image by AIRCAS)