Himalayan glacier disaster highlights risks of climate change


NEW DELHI – When Ravi Chopra saw the devastating deluge of water and debris crash downriver from a Himalayan glacier on Sunday, his first thought was that this was exactly the scenario his team had warned the Indian government about in 2014.

At least 31 people have died, 165 people are missing and many are feared to have died. The deluge first slammed into a small dam, accumulating more energy as it became heavier from debris it collected along the way. Then it crashed into a larger dam under construction and gathered even more energy.

The Supreme Court of India commissioned Chopra and other experts to study the impact of retreating glaciers on dams. They had warned that warming due to climate change was melting Himalayan glaciers and facilitating avalanches and landslides, and that damming the fragile ecosystem was dangerous.

“They were clearly warned and yet they kept going,” said Chopra, director of the nonprofit People’s Science Institute.

National Disaster Response Force (NDRF) personnel carry a body recovered from the rubble after part of the Nanda Devi glacier broke off in Reni, in the northern state of Uttarakhand, India.  At least 31 people have died, 165 people are missing and many are feared to have died.
National Disaster Response Force (NDRF) personnel carry a body recovered from the rubble after part of the Nanda Devi glacier broke off in Reni, in the northern state of Uttarakhand, India. At least 31 people have died, 165 people are missing and many are feared to have died.
AP

Scientists first suspected that a glacial lake had erupted on Sunday. After examining satellite images, they now believe that a landslide and avalanche were the most likely causes of the disaster. It is unclear whether the landslide caused an avalanche of ice and debris, or whether the falling ice resulted in the landslide, said Mohammad Farooq Azam, who studies glaciers at the Indian Institute of Technology in Indore.

What is known is that the mass of rock, boulders, ice and snow collapsed Sunday down a 2-kilometer (1.2-mile) mountainside near vertical. And now scientists are trying to find out if the heat produced due to friction would be enough to melt snow and ice and cause a flood of water, he said.

Experts say the disaster underscores the fragility of the Himalayan mountains, where climate change is altering the lives of millions of people.

Even if the world meets its most ambitious climate change goals, rising temperatures will melt a third of the Himalayan glaciers by the end of the century, according to a 2019 report from the International Center for Integrated Mountain Development. Himalayan glaciers are melting twice as fast since 2000 than in the previous 25 years due to human-caused climate change, researchers reported in Science Advances in 2019.

It is not known if this particular disaster was caused by climate change. But climate change can increase landslides and avalanches. As glaciers melt due to warming, valleys that were previously packed with ice open up, creating room for landslides to enter. In other places, steep mountain slopes may be partially “glued” to each other by ice frozen firmly within their crevices.

“As the warming occurs and the ice melts, the pieces can move downhill more easily, lubricated by the water,” explained Richard B. Alley, professor of earth sciences at Pennsylvania State University.

Satellite image published by Planet Labs, Inc., shows Uttarakhand, India, after part of the Himalayan glacier broke.  India's Supreme Court commissioned experts to study the impact of retreating glaciers on dams.  They had warned that warming due to climate change was melting Himalayan glaciers and facilitating avalanches and landslides, and that building dams in the fragile ecosystem was dangerous.
Satellite image published by Planet Labs, Inc., shows Uttarakhand, India, after part of the Himalayan glacier broke. India’s Supreme Court commissioned experts to study the impact of retreating glaciers on dams. They had warned that warming due to climate change was melting Himalayan glaciers and facilitating avalanches and landslides, and that building dams in the fragile ecosystem was dangerous.
AP

With warming, ice is also becoming less frozen: before, its temperature would range from minus 6 degrees Celsius to minus 20 C and now it’s minus 2 C (from 21.2 degrees Fahrenheit to minus 4 F previously at 28.4 F now), he said. Azam. The ice is still frozen, but closer to its melting point, so it takes less heat to trigger an avalanche than it was a few decades ago, Azam added.

Another threat is the explosion of a glacial lake, which some initially suspected was the cause of Sunday’s disaster. The danger posed by these sprawling lakes cannot be ignored, said Joerg Michael Schaefer, a climate scientist who specializes in ice and especially Himalayan glaciers at Columbia University.

The water that lakes release into rivers contains the energy equivalent to “various nuclear bombs” and can provide clean, carbon-free energy through hydroelectric projects, Schaefer said. But it is dangerous to install power plants without looking uphill and mitigate risk by drawing water from lakes to control levels, he said.

“The sheer force of these things is really mind-boggling,” especially if they break, he said. “You cannot tame that tiger. You have to avoid that. “

The Uttarakhand state government said it was continually faced with an “acute power shortage” and was forced to spend $ 137 million each year to buy electricity, documents filed with the Supreme Court of India show. The state has the second highest hydropower generation potential in India, but experts say that solar power and wind power offer more sustainable and less risky alternatives in the long term.

Development was needed to improve the impoverished region, but experts said such projects should take into account the ecological fragility of mountains and the unpredictable risks posed by climate change.

A view of the remains of the Tapovan Hydroelectric Power Dam.  Even if the world reaches its most ambitious climate change goals, rising temperatures will melt a third of the Himalayan glaciers by the end of the century.
A view of the remains of the Tapovan Hydroelectric Power Dam. Even if the world reaches its most ambitious climate change goals, rising temperatures will melt a third of the Himalayan glaciers by the end of the century.
AP

For example, during the 2009 construction of the second dam that was hit by the flood on Sunday, workers accidentally drilled an aquifer. Enough water to drink 2 to 3 million people was drained at the rate of up to 70 million liters (18.5 million gallons) every day for a month and villages in the area suffered from water shortages.

Development plans should “be in accordance with the environment” and not against it, said Anjal Prakash, a professor at the Indian School of Business who has contributed to research on the impacts of climate change in the Himalayas for the Intergovernmental Panel on Climate Change.

“Climate change is here and now. It is not something that will happen later, ”he said.

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