Glacial Lake Outbursts Threaten 15 Million People with Potential Flooding

Glacial lake outbursts are threatening the lives of communities with roughly 15 million people amid potential flooding and inland tsunamis.

Researchers published a report on Tuesday where they warned that melting mountain glaciers are endangering millions of lives, primarily communities in Asia. Runoff water from melting glaciers commonly gathers in shallow lakes and is held back by rocks and debris.

The Threat of Glacial Lake Outbursts

The threat that the team of researchers detailed comes when a lake overfills and bursts through its natural barrier, sending a torrent of water flowing down mountain valleys. Scientists have now assessed, for the first time, how many people worldwide could be impacted by these floods.

They found that more than half of vulnerable populations live in India, Pakistan, China, and Peru. The study reported that the danger is highest among communities with large populations who live near a lake.

In a statement, the study's co-author, Stuart Dunning, a physical geographer at Britain's Newcastle University, said that their work focused on more than just the size or number of glacier lakes. Instead, it also considered the presence of people, especially vulnerable people, in the landscape that causes a disaster, as per Reuters.

Experts are projecting glacial lake outburst floods to worsen due to a warming climate caused by global warming. The world's glaciers collectively lost roughly 332 gigatons of ice per year from 2006 to 2016. The number and volume of glacial lakes worldwide have each increased by about 50% since 1990.

Some 9 million people in the high mountains of Asia live near more than 2,000 glacial lakes. Two years ago, over 100 people were reportedly killed in India due to an outburst of flood in the country's northern mountains.

When compared with mountain glaciers in the Alps and North America, Asia's icy plates are less well monitored by scientists. Most of these plates need long-term observations that observe how they have changed over time.

Caused by Global Warming

Glacial lakes rise as temperatures get warmer, causing more pieces of glaciers to melt away. This puts people living downstream from one of these lakes at high risk. According to CNN, if the lakes' water levels rise too high or the surrounding land or ice gives way, it could burst.

A study's co-author, Tom Robinson, a senior lecturer at the University of Canterbury in New Zealand, said that a glacial lake outburst is similar to an "inland tsunami." He said that the event is similar to the impact of a sudden dam collapse.

In an interview, Robinson noted that glacial dams are similar to constructed dams in that if they were suddenly removed, the massive lake behind it would go somewhere else. These glacial lake outbursts happened with little to no warning.

One flood in Peru in 1941, considered one of the most devastating, resulted in the death of between 1,800 and 6,000 people. In 2020, a glacial lake outburst in British Columbia, Canada, caused a flood that, in turn, created a tsunami of water roughly 330 feet high, said ABC News.