Graphic by Annabel Driussi for ODP

by Amy Lupica, ODP Staff Writer

More than 171 people are missing and 26 have died after a Himalayan glacier burst occurred, sending a wall of water and rocks hurtling through a dam and two hydroelectric project sites in northern India. The flash floods have impacted 13 villages and about 2,500 people. While rescuers are hard at work clearing debris and searching for victims, climate scientists are concerned about future disasters from melting glaciers in the region.

Why This Matters: A 2019 study found that Himalayan glacier melt has accelerated by 100% in the last century, and if greenhouse gas emissions continue at current rates, the Himalayas could lose two-thirds of its glaciers before this century is over. Glaciers in the Hindu Kush Himalayan Region span 2,000 miles of Asia and provide drinking water for about 25% of the world population, nearly 2 billion people. These events aren’t new; glacier bursts can happen for a variety of reasons, including landslides and normal thaw cycles.

• In 2013, a glacier burst in the same region of northern India killed 6,000.
• In Peru in 1941, a glacier burst swept through a populated village, killing about 6,000 people.

But experts say that these events will become more frequent and more devastating as warming temperatures destabilize glaciers across the globe.

On Thin Ice: Glacier bursts can occur when landslides knock ice and water free from mountain glaciers. These glaciers undergo freeze/thaw cycles where new snow will compact freeze over the existing snow and ice from the previous cycle. Thaw cycles leave the glaciers more vulnerable to damage and bursts; as global temperatures warm, these thaw cycles become warmer and longer. In this recent case, a landslide occurred, knocking out a part of one such vulnerable glacier.

The water knocked free can travel extremely fast and with great force. 

• In the northern Indian state of Uttarakhand’s Chamoli district, after the rush hit the first hydroelectric power station officials attempted to dispatch emergency cell phone warnings to those in the direct path of the “tsunami,” but workers at a second plant received the alert only minutes before being hit by the flooding, and only 15 out of 176 workers were able to evacuate in time.
•  Local resident Sanjay Singh Rana described his fear when the flooding reached his village, “It came very fast, there was no time to alert anyone. I felt that even we would be swept away.”

Uttarakhand government officials stated that the burst was “a one-time incident,” a claim met with much criticism from the science community, who have been warning the government for years that unchecked development in the region would increase the chances of disasters like this one.

Weighing Risk: It’s not just the Himalayas that scientists are worried about. Glaciers like these exist on every continent, and nearly every single one is undergoing rapid melting due to climate change. Many glacier burst risks have been identified across the globe, including in the Himalayas and the Andes region of South America. Even so, scientists struggle to discern when these bursts will occur, and measuring melt and risk in remote areas like the Himalayas can be difficult and dangerous.

Experts worry that existing infrastructure in these remote regions won’t be able to withstand future bursts, but building that infrastructure could further destabilize the rapidly thawing glaciers. Sarah Das, an associate scientist at the Woods Hole Oceanographic Institution explained, “Many of these lakes are upstream of steep river valleys and have the potential to cause extreme flooding when they break. Where these floods reach inhabited regions and sensitive infrastructure, things will be catastrophic.”