The Third Pole, which spans the Tibetan Plateau and its surrounding Himalayan, Hindu Kush, and Tien Shan mountains, is extremely vulnerable to the effects of climate change. Rising temperatures and changing rainfall patterns have caused more than 10,000 glaciers in the region to retreat over the past 30 years, spurring the formation of thousands of glacial lakes.
Although these bodies of water appear harmless, they have highly destructive potential, especially as they can cause glacial lake outburst floods (GLOFs). Triggered by events such as glacier collapse, avalanches, landslides, and natural dam failures, large amounts of water can be rapidly released from glacial lakes, creating potentially destructive GLOFs.
Because GLOFs pose an immense threat to communities and industries located near third-polar glacial lakes, efforts are underway to understand their triggers and assess their risks, with the aim of facilitating proactive decision-making. It has been. Unfortunately, the methods used to assess these risks vary widely across these studies. For example, the number of reported glacial lakes varied from 10,000 to 30,000 from 2015 to 2020, depending on the definition used. These discrepancies make it difficult to create reliable datasets for further data analysis and GLOF risk assessment.
Against this background, a research team led by Associate Professor Wang Weicai of the Institute of Tibetan Plateau Research, Chinese Academy of Sciences, decided to conduct a more detailed analysis of GLOF risks in the Third Pole. This research nature communications The journal emphasizes the need for urgent action and regional cooperation for the economically disadvantaged and highly vulnerable regions of the Third Pole.
To accomplish this goal, the researchers first acquired satellite images from the Sentinel 2A and Sentinel 2B missions from 2018 to 2022. We then identified and classified all glacial lakes based on their location and topographic features in relation to their source glaciers. This updated glacial lake inventory, combined with previous datasets, allows us to analyze changes in the region over the past few decades, revealing an alarming and continued expansion of glacial lakes. .
Additionally, they analyzed changes in GLOF activity by integrating a dataset of GLOF events at the Third Pole dating back to 1900. Their findings, in contrast to previous studies, revealed an alarming trend, showing an increase from the average in GLOF occurrence. From 1981 to 1990, there were 1.5 events per year, and from 2011 to 2020, there were 2.7 events per year. Researchers noted that the expansion of glacial lakes and the emergence of new glacial lakes will likely lead to an increase in the number of annual GLOFs in the future, and to stay one step ahead of potential disasters. It highlights the need to develop better analytical methods and datasets. .
Finally, the researchers analyzed the effects of GLOF on 5,535 glacial lakes and identified 1,499 of them with a high potential for outburst flooding. The researchers also investigated the “potential disaster volume” based on GLOF simulations of these high-risk lakes. The results were alarming, to say the least. “Approximately 55,808 buildings, 105 existing or planned hydropower projects, 194 km2 of agricultural land, 5,005km of roads and 4,038 bridges are under potential GLOF threat,” Dr Wang said. “Additionally, by utilizing regional population distribution data, we estimated that approximately 190,000 lives were directly exposed within his GLOF pathway,” he explains.
Overall, these findings are particularly worrying for countries exposed to GLOF in the third pole, especially China, Kazakhstan, Nepal, India, and Pakistan. “Our findings highlight the significant challenges posed by the potential mass disasters in these economically disadvantaged and highly vulnerable regions,” Dr. Wang said. It further explains that “Given the predicted escalation of GLOF threats under future climate change scenarios, relevant countries around the Third Pole recognize the urgency of addressing GLOF threats and promote regional cooperation. is extremely important.”
In the future, it is hoped that this initiative will lead to better risk management strategies for GLOF and promote cooperation among third-polar countries. Additionally, and perhaps most importantly, these findings also raise awareness of the many ways climate change threatens our way of life.