According to New Zealand and British scientists, about 15 million people worldwide may be at risk of glacial lake outburst flooding, with populations in the high mountains of Asia (India, Pakistan, China) and the Andes (Peru and Bolivia) facing the greatest threat. According to the study, more than half of the world’s exposed population is concentrated in four countries: India, Pakistan, Peru and China. The study was published February 8 in Nature Communications.
As the glacier melts as the climate warms, meltwater merges into lakes near the glacier. These lakes can cause huge natural disasters in the form of glacial lake outburst floods. Such floods occur when natural dams containing glacial lakes fail, often without warning. Glacial lake outburst floods can cause property damage, damage to infrastructure and historically cause massive deaths.
Lake Dig Tsho in Nepal’s Langmoche Valley. The lake was catastrophic in 1985 when an ice avalanche caused a catastrophic breach in pulses, causing extensive damage to a newly completed hydroelectric power station and valuable local infrastructure and property. The Asian alpine region has the highest risk of glacial lake outbursts globally and accounts for the majority of the world’s population exposed to glacial lake outbursts. Photo by Matthew Westoby
Tom Robinson of the University of Canterbury, Caroline Taylor of the University of Newcastle and collaborators mapped the situation, exposure and vulnerability of glacial lakes around the world to quantify and rank the potential for glacial lake outburst flood damage in 2020. They found that people living in India, Pakistan, China, Peru, and Bolivia had the highest levels of exposure.
The researchers emphasize that the Andes is an understudied hotspot for glacial lake outburst flooding, and more detailed studies of the area are needed. They point out that the most dangerous places are not the largest, largest and fastest growing places of glacial lakes, but rather the size of the local population and the ability of people to respond to disasters are the key to determining risk.
View of the natural dam and glacial lake at the foot of Bhutan’s Chori Lamu Peak. Bhutan has glacial lakes that are larger than the size of the country, posing a great danger to the downstream population, and past glacial lake outbursts and floods have caused great damage. Bhutan has undergone some dramatic changes in population and lake exposure conditions over the past 20 years and may soon become one of the places with the highest risk of glacial lake outbursts. Photo by J. Rachel Carr
Taylor said that by identifying areas with the highest risk of glacial lake outburst flooding, the findings may be used to implement more targeted glacial lake outburst flood risk management. How the threat of glacial lake outbursts and floods will change in the future remains to be discussed. As glaciers continue to retreat under the effects of climate change, current glacial lakes will continue to expand, and many new lakes will be formed, changing the spatial pattern of glacial lake outburst flood threats. Further research is needed on changes in lake conditions, exposure, and vulnerability over time to clarify the relative impact of each factor on GLOF threats. (Source: Feng Weiwei, China Science News)
Related paper information:https://doi.org/10.1038/s41467-023-36033-x