In a dramatic ecological event, Tibet’s largest inland lake, Siling, has overflowed into the nearby salt lake Bange, marking the first such occurrence in over 4,000 years. Scientists attribute this rare phenomenon to the impacts of climate change.
A historical spill
Siling Lake, the largest inland lake in Tibet, has begun to spill into the adjacent Bange Lake. According to a report by the South China Morning Post (SCMP), researchers observing these lakes on the Tibetan plateau have indicated the two bodies of water might soon merge.
The two lakes, situated merely four miles (6.44 km) apart, have remained hydrologically disconnected for millennia—possibly dating back 8,200 years, a period marked by rising sea levels due to glacier melting.
In September 2023, Siling’s waters breached an ancient riverbed lying between the two lakes.
Scientific insight and warnings
Lei Yanbin, a professor at the Institute of Tibetan Plateau Research at the Chinese Academy of Sciences, led a study analyzing the changes at Siling Lake. The findings, published in the peer-reviewed journal Science Bulletin in July, underscore the need for proactive measures. “Real-time monitoring and early warnings for critical lake water level changes are needed to protect surrounding roads, bridges, and villages from emerging threats,” Lei stated.
Siling’s significant expansion
Over the past two decades, Siling Lake has experienced substantial growth. In the 1970s, the lake spanned approximately 1,640 sq km (630 sq miles). By 2023, it had expanded to 2,445 sq km (945 sq miles), as per Lei’s analysis.
“While Bange water level decreased by about one metre [3 feet] over the last decade, Siling rose by four metres [13 feet],” noted Lei.
Should Siling and Bange merge, the impact on local communities could be profound. “The outburst flood … will lead to the rapid expansion of Bange,” Lei explained. “Satellite data revealed that within a month of the overflow, Bange’s area had increased by more than 10 per cent.”
The immediate cause of this overflow is a steady rise in Siling’s water levels over the past 20 years—an overall increase of about 13 metres between 1998 and 2023, exacerbated by heavy rainfall in August and September of the previous year.
Future projections
Lei and his team attribute these changes to climate change, estimating that by 2100, Siling Lake’s water levels could rise by another 16.8 metres. They predict that Siling and Bange could merge around 2030.
The unfolding situation highlights the urgent need for environmental monitoring and adaptation strategies to mitigate the growing risks posed by climate change on the Tibetan plateau.