As the glaciers of the world melt, it leaves about 15 million people vulnerable to a calamity which could uproot their lives, suggests a study conducted by Newcastle University, England. About 270 billion tonnes of ice has been lost annually within the first two decades of the 21st century. With glaciers melting at this pace, the world is seeing an increase in global sea levels as well as increasing the chances of glacial lake outburst floods (GLOF). In the last 70 years, thousands of people have died due to glacial floodings in Cordillera Blanca, Peru. The aim of this study is to map out potential hotspots in order to better prepare the stakeholders.
Glacial lakes are a naturally occurring phenomenon, when the water from the melting glaciers gets accumulated in a natural cavity created due to glacial erosion, or gets blocked by naturally occurring rock formations in the mountains. At present, these lakes are increasing at an alarming rate, both in terms of amount and volume. Since 1990, there has been an increase of 53 per cent in the amount of such lakes, and that of 48 per cent (156.5 km3) in their volume.
As per the UN, irrespective of any efforts, a third of the glaciers present at UN World Heritage sites are earmarked for extinction by 2050, including the last ones in Africa. The remaining two thirds can still be saved if we manage to keep the rising global temperature below 1.5° Celsius. The last of the glaciers in Mount Kilimanjaro, Tanzania and the Yosemite National Park, along with those in the Alps will melt away by 2050.
The major areas to face the risk of GLOF include India, Pakistan, Peru, and China where about a million people live within a 10km radius of a glacial lake. GLOF is an outcome of dam failures which can be triggered when a piece of rock falls into a glacial lake generating tidal waves that break the dam as they hit it, or it could simply be due to over accumulation of water creating pressure that makes the dam lose ground.
Since it’s difficult to predict when or which of these dams would break, the researchers of the study focused more on the scale of damage that these floods can wreak. Since these floods have the capability of destroying pivotal infrastructure and can occur without little prior warning, the study suggested necessary safety measures in place, including a time lapse camera to monitor the rising levels of these lakes.