The lakes on the Qinghai-Tibet Plateau are quietly "expanding"

The Qinghai-Tibet Plateau is home to the world's highest-altitude lakes, with more than 1,400 lakes larger than 1 square kilometer and a total lake area of ​​more than 50,000 square kilometers. They are an important part of the regional water cycle and play an important role in regulating the regional climate and maintaining ecological balance. Against the backdrop of climate warming and humidification and rapid melting of the cryosphere, the lakes in the inland areas of the Qinghai-Tibet Plateau have generally expanded rapidly since the late 1990s. The continued expansion of the lakes has led to a reorganization of the water system in the inland areas of the plateau, such as overflow of closed lakes and merging of adjacent lakes. This process not only significantly affects the regional landforms and lake water quality changes, but also has different impacts on surrounding infrastructure and human living environments.

Since 2013, researchers have set up automatic weather stations, water level gauges, temperature chains, etc. at more than a dozen lakes, including Peikucuo, Zharinamcuo and Dazecuo in northern Tibet, and carried out continuous monitoring of lake water levels, lake runoff, lake water temperature, glacier meltwater, and other hydrological and meteorological elements, keeping a close eye on the changes in lake water on the Qinghai-Tibet Plateau.

Image 1: Dawa Co is located in Coqen County, Ngari Prefecture, at an altitude of about 4,600 meters. This place is famous for its beautiful natural scenery and is also an important breeding ground for migratory birds. Due to the rising water level, it is about to merge with another small lake, Qingmu Co, on the east side. The picture shows the boundary between the two lakes that is about to disappear.

Image source: Second Qinghai-Tibet Expedition Team

Picture 2: Dangre Yongcuo, one of the four sacred lakes in Tibet, is the fourth largest lake in Tibet, with a maximum depth of 230 meters. Its southern end has a very spectacular ancient lakeshore, reflecting the gradual shrinkage of the ancient lake since the last deglacial period. However, in the past decade or so, the lake water has begun to submerge the ancient lakeshore below again, indicating that the water level is constantly rising.

Image source: Second Qinghai-Tibet Expedition Team

Image 3: Daze Co Lake, located in the hinterland of the Qiangtang No Man's Land, has a lake surface elevation of 4,459 meters, is 21.1 kilometers long from east to west, 11.6 kilometers wide from north to south, and covers an area of ​​244.7 square kilometers. Since 2013, observations have been carried out on the lake's water level, runoff into the lake, and lake water temperature profiles, as well as upstream glacier hydrometeorological research.

Image source: Second Qinghai-Tibet Expedition Team

Picture 4: Caiduo Chaka Lake, which is located in Shuanghu County, Tibet. Over the past 20 years, the lake has expanded rapidly and merged with the upstream Dirangbi Co, flooding the road from Shuanghu County to Yaqu Township, forcing the road to be rerouted. The newly built bridge in the middle of the picture was originally the land where the two lakes met.

Image source: Second Qinghai-Tibet Expedition Team

Image 5: Selin Co, the largest lake in Tibet, is also the fastest rising lake. Its area has increased from 1,640 square kilometers in 1976 to 2,445 square kilometers in 2023. The increase in lake area in the past 10 years is nearly four times that of the previous 24 years.

Image source: Second Qinghai-Tibet Expedition Team

Image 6: Namtso Lake, one of the four sacred lakes in Tibet, is also a favorite destination for tourists. It used to be the largest lake in Tibet. Before 2010, the lake was always expanding, but there was no significant expansion after that. As the area of ​​Selin Co increased dramatically, its throne as the largest lake was also taken away by Selin Co.

Image source: Second Qinghai-Tibet Expedition Team