Uttarakhand has been inclined to disasters owing to its pure geography. However, the February 7 catastrophe in the hilly terrain of Chamoli will stay one of the crucial tragic with over 200 folks being killed or reported lacking.
The particles circulation that went viral on social media and the ensuing tragedy that destroyed two hydropower tasks in the area was attributed to a glacier outburst. Now, a group of 53 scientists from internationally have printed a report analysing what occurred on that fateful day.
The research contradicts previous claims and states that the tragedy began on high of the 6 km-high Ronti peak, the place a big mass of ice and rock dislodged from the slopes triggering a large landslide that reworked into mud and particles circulation inflicting destruction alongside its path. The large mass of rock on the Roti peak had already been shifting since 2016 and satellite tv for pc pictures confirmed it had slipped a number of tens of metres through the years.
The report published in the journal Science takes under consideration satellite tv for pc imagery of the area, eyewitness accounts and seismic data to generate a pc mannequin of the catastrophe.
A flash flood tragedy hit the Chamoli district of Uttarakhand on February 7 following a glacier burst in the Himalayas. (Photo: Screengrab)
What actually occurred?
The rock and ice avalanche quickly reworked into an “extraordinarily large and mobile debris flow” that transported boulders over 20 meters in diameter and deposited 27 million cubic metres of fabric down the slope inside a minute of the descent.
After the rock and ice avalanche impacted the valley flooring, most of it moved downstream, “Heating of the ice in the avalanche generated liquid water that allowed the transition in flow characteristics, becoming more fluid down the valley, creating a flow consisting of sediment, water, and blocks of ice,” the researchers stated. As the large block of ice moved it cooled from -8°C to 0°C after which melted by frictional heating producing a large quantity of water.
“The calculated 80 per cent rock in the avalanche completely converted the 20 per cent glacier ice into water over the 3200-meter elevation from Ronti Peak to the Tapovan hydropower plant. This conversion is largely responsible for the devastating impact of the resulting mud and debris flood wave,” Andreas Kääb, from the University of Oslo, said.
The particles circulation generated a robust air blast that flattened almost 20 hectares of forests. (Photo: Ritesh Mishra/ India Today)
The particles circulation generated a powerful air blast that flattened nearly 20 hectares of forests. By the time it reached Rishiganga hydroelectric plant, the massive debris flow had gained a speed of 90 kilometres per hour without any warning to those working at the plant.
The co-authors of the study from Wadia Institute of Himalayan Geology conducted a field reconnaissance of the area and concluded that a bottleneck was created at the confluence of Rishiganga River with Dhauliganga River that furthered the damage in the area.
The tragedy destroyed two hydropower tasks in the area. (Photo: Javed Akhtar/India Today)
Is climate change the reason?
While there was speculation of climate change as the reason behind the outburst, researchers have not attributed it directly. Instead, they said that it has led to rockfalls and landslide in the mountainous region. However, they said “Regional local weather and associated modifications in frozen ice may have interacted in a fancy manner with the geological options to produce this huge slope failure.”
The researchers said that the sensitivity of glaciers and permafrost to climate changes is exacerbating these hazards. They used satellite imagery from Landsat and the European Space Agency’s Copernicus Sentinel-2 mission to quantify the total volume, elevation differences and travel distances of the debris flow.
Over 200 people were killed or are presumed dead in the disaster. (Photo: Ritesh Mishra/India Today)
Earlier the government had claimed that the Chamoli disaster was due to a glacier burst that reportedly took place due to heavy snowfall in the region. While agencies had recovered 68 bodies in the post-tragedy search and rescue operations, the Uttarakhand government had in late February notified that the 136 persons missing in the Chamoli tragedy in Uttarakhand will be declared “presumed lifeless”.