Historic glacial lake outburst flood (GLOF) recorded in East Greenland

One of the three largest glacial lake outburst floods (GLOF) by outflow rate occurred in Eastern Greenland between September 23 and October 11, when Catalina Lake released approximately 3.4 km³ (0.82 mi³) or about 3 billion liters (792 million gallons) of water into Scoresby Fjord.

The water level of Catalina Lake dropped to approximately 154 m (505 feet) during the event, which was monitored in real-time by scientists from the University of Copenhagen’s Niels Bohr Institute using satellite imagery.

The outburst occurred over approximately 20 days, with a peak discharge rate of 7 200 m³/s (254 000 feet³/s), more than double the peak flow of Niagara Falls.

The outburst flood was triggered by 20 years of meltwater accumulation in Catalina Lake, located in a valley blocked by the Edwards Bailey Glacier. Rising water pressure lifted the glacier, carving a 25 km (16 miles) long tunnel beneath it and releasing the water into the world’s largest fjord.

“We have previously found traces of similar outburst floods. However, due to polar night and cloud cover obstructing satellite observations, this is the first time researchers have monitored such an event and measured water volumes in real-time,” said Aslak Grinsted, a climate researcher at the Niels Bohr Institute.

According to Grinsted, it’s worth considering how to harness the immense energy of such natural phenomena as a source of green energy.

In theory, the energy released from the Catalina Lake event could have continuously provided 50 megawatts of electricity, enough to meet the needs of a small town. However, in this instance, the nearest settlement is 180 km (112 miles) away and inhabited by a mere 350 residents – posing a significant technological challenge for energy utilization.

“As with many other natural resources in Greenland, infrastructure is a problem. But if a brilliant engineer could figure out how to harness these meltwater outbursts, there’s enormous power and energy potential in them,” concludes Grinsted.

Although glacial lake outburst floods can be catastrophic in densely populated regions like the Himalayas, where they often devastate villages, this particular event caused no harm due to Greenland’s sparse population.

However, a 2023 study found that 15 million people worldwide live under the threat of deadly glacial floods.

“I expect that we will witness outbursts from even larger ice-dammed lakes as Greenland’s ice sheet retreats in the coming centuries,” said Grinsted. “At the end of the last Ice Age, Lake Missoula experienced an outburst 2 500 times larger than the recent Catalina event. To understand these immense forces, we must study the largest outbursts as they occur,” he added.

Historically, over 12 000 people worldwide have died due to GLOFs, with most fatalities occurring in South America and Central Asia.

University of Copenhagen scientists are saying the number and size of glacial lakes have grown significantly since 1990s.

References:

¹ One of the world’s largest glacier floods triggered in Greenland – University of Copenhagen – December 11, 2024