Over 15m people, with more than half of these living in China, India, Pakistan and Peru, are at risk from flooding caused by glacial lakes according to a new international study.
The study published in a recent issue of Nature Communications and conducted by an international team of scientists has revealed that the number of glacial lakes has grown rapidly since 1990 as a result of climate change and at the same time, the number of people living in these catchments has also increased significantly. Newcastle University head of physical geography and co-author of the study Rachel Carr said, “Understanding which areas face the greatest danger from glacial flooding will allow for more targeted and effective risk management actions which in turn will help minimize loss of life and damage to infrastructure downstream as a result of this significant natural hazard.”
The research team looked at 1,089 glacial lake basins worldwide and the number of people living within 50kms of them, as well as the level of development in those areas and other societal indicators as markers of vulnerability to glacial lake outburst floods (GLOFs). They then used this information to quantify and rank the potential for damage from GLOFs at a global scale and assess communities’ ability to respond effectively to such a flood.
The results highlighted that 15m people live within 50km of a glacial lake and that high mountain Asia (which encompasses the Tibetan plateau, from Kyrgyzstan to China), has the highest GLOF danger, with 9.3m people potentially at risk. India and Pakistan have around 5m exposed people – about one third of the global total combined.
Newcastle University doctoral researcher and lead author Caroline Taylor said, “This work highlights that it’s not the areas with the largest number or most rapidly growing lakes that are most dangerous. Instead, it is the number of people, their proximity to a glacial lake and importantly, their ability to cope with a flood that determines the potential danger from a GLOF event.”
What are GLOFs? As the climate gets warmer, glaciers retreat and meltwater collects at the front of the glacier, forming a lake. These lakes can suddenly burst and create a fast-flowing GLOF that can spread over a large distance from the original site – more than 120km in some cases. GLOFs can be highly destructive and damage property, infrastructure, and agricultural land and can lead to significant loss of life.