Warming swells glacial lakes, endangering thousands

IRIN: As global warming shrinks glaciers along the world’s highest peaks, glacial lakes in Nepal are increasingly at risk of bursting the natural dams containing them - endangering the lives of tens of thousands in communities below, experts say. Nepalese authorities have identified about 20 “priority” lakes at risk of leading to glacial lake outburst floods (GLOFs), and are using various methods to reduce the volume of water in some of them.

“With climate change causing the rapid melting of glaciers, the glacial lakes are growing so quickly that the risk of a disaster occurring throughout the Himalayas is increasing,” said Pradeep Mool, of the International Centre for Integrated Mountain Development (ICIMOD), a Kathmandu-based organization funded by eight countries that researches climate change and mountain ecosystems.

“GLOFs come very fast, carry great big boulders; they can push down rock walls and destroy river banks. The destructive impact is very, very high,” Mool told IRIN by phone from Kathmandu.

GLOFs occur when the natural dams of ice or rock containing glacial lakes collapse because the lake has rapidly increased in size or its walls are shattered by earthquakes or avalanches. The resulting floods can cause rivers downstream to rise up to 35 metres, destroying everything in their path for up to 100km in only eight hours, he added….

Glacial lakes in Bhutan, from NASA