Introduction To Glacier Collapse
The recent glacier collapse in the Nepali Himalayas has raised concerns about a new kind of risk in a world warmed by climate change. The devastating flooding unleashed by the collapse has killed at least 584 people and left more than 2,400 missing. Scientists are warning that similar phenomena could occur elsewhere, and the risk is amplified by the terrain and high tectonic activity in the Himalayas.
Understanding Glacier Collapse
A glacial collapse is similar to an avalanche, but instead of snow descending from a mountain slope, falling ice gathers energy and debris into a fast-flowing, destructive mixture. The glacier in question was likely a cirque glacier, which is a glacier that has formed in a depression or basin high in the mountains. According to Dan Shugar, an Earth scientist at the University of Calgary, new satellite imagery shows that the glacier was only part of what failed, and it looks to have been a large rock avalanche that took part of the glacier with it.
Climate Change Link
Several scientists have urged caution about linking the latest disaster to climate change, although some experts are already drawing connections. Etienne Berthier, a glaciologist at the French National Centre for Scientific Research, notes that while the collapse itself may not be directly caused by climate change, the risk of similar phenomena is amplified by the terrain and high tectonic activity in the Himalayas. Tristram Hales, a professor of environmental hazards at Cardiff University, warns that rockfalls and landslides triggered by earthquakes or the thawing of permafrost, which is being accelerated by climate change, are more likely than entire sections of a mountain coming down.
Rising Global Hazard
The resulting flood was triggered by a glacier collapse so violent that it generated energy equivalent to a magnitude 5.2 earthquake and caused numerous landslides. Scientists are warning that the number of extremely hazardous flows, such as glacial lake outburst floods (GLOFs), has increased dramatically in the past decade or so. Ludovic Ravanel, a geomorphologist at the CNRS, notes that this year's extremely hot summer saw a record number of rockfalls in the Alps, including some that were fatal, and the vast majority of which can be attributed to the climate crisis.
Prediction And Prevention
While the disaster in Nepal was probably very hard to predict, scientists are working to analyze rock movements to see whether signs of instability were visible in the preceding weeks or months. Bernard Francou, a retired glaciologist and former research director at the French National Research Institute for Sustainable Development, notes that in the Alps, they are well-equipped to monitor glacier-fed lakes and check for risks of overflowing or sudden drainage. However, the risk of similar phenomena occurring elsewhere is still present, and scientists are urging caution and increased monitoring to prevent such disasters in the future.
Future Outlook
The glacier collapse in Nepal has highlighted the need for increased awareness and monitoring of glacier-related hazards. As the climate continues to change, the risk of similar phenomena occurring elsewhere is likely to increase. Scientists are warning that the number of extremely hazardous flows, such as GLOFs, will continue to rise, and it is essential to take proactive measures to prevent such disasters in the future. By understanding the mechanisms behind glacier collapse and the links to climate change, we can work towards mitigating the risks and protecting communities from the devastating effects of these events.
Sources
This is an original synthesis by Qivorane based on reporting from the outlets below.
