A flash flood surged down a river in India’s Himalayan Uttarakhand state on February 7, killing a minimum of 30 individuals and getting rid of 2 hydroelectric power stations.
As rescue employees look for more than 100 individuals who are still missing out on, officials and scientists are trying to unwind the reasons for the sudden flood. Did a glacier high up in the mountains collapse, releasing a big plug of frigid meltwater that spilled into the river? Or was the culprit a landslide that then set off an avalanche? And what, if any, link might these occasions need to an altering environment?
Here are 3 things to know about what might have caused the disaster in Uttarakhand.
1. One possible offender was the sudden break of a glacier high in the mountains.
News reports in the instant wake of the catastrophe recommended that the floodwaters were caused by the sudden overflow of a glacial lake high up in the mountain, an occasion called a glacial lake outburst flood.
” It’s likely prematurely to know what exactly occurred,” states Anjal Prakash, the research study director of the Bharti Institute of Public Policy at the Indian School of Organization in Hyderabad. Satellite images show that an area of a glacier broke off, but how that break associates with the subsequent floods is still unidentified. One possibility is that the glacier was holding back a lake of meltwater, and that heavy snowfall in the region two days earlier added sufficient volume to the lake that the water required its way out, breaking the glacier and surging into neighboring rivers.
This situation is definitely in line with known threats for the area.
2. A landslide may be to blame rather.
Other researchers contend that the catastrophe wasn’t caused by a glacial lake outburst flood at all.
” WOW,” he composed on Twitter the morning of February 7, posting side-by-side satellite shots of a dark location of possible “huge dust deposition,” contrasted versus the exact same snowy, beautiful area simply the day before.
Landslides– the abrupt failure of a slope, sending out a rush of rocks and sediment downhill– can be triggered by anything from an earthquake to an intense deluge of rain. In high, snowy mountains, cycles of freezing and thawing and refreezing once again can also begin to break the ground apart; the ice-filled cracks can gradually widen in time, setting the stage for sudden failure, and then, disaster.
The satellite images seem to point plainly to such a landslide, rather than a common glacial lake overflow, Shugar says.
However, a distant question for this hypothesis is where the floodwaters came from.
3. It’s not yet clear whether climate modification contributed in the disaster.
The threat of both glacial lake outburst floods and freeze-thaw-related landslides in Asia’s high mountains has increased due to environment change.
The region, that includes the Hindu Kush Himalayan mountains and the Tibetan Plateau, “has been an environment modification location for a pretty long time,” Prakash states. The region is often called Earth’s third pole, since the stores of ice and snow in the Himalayan watershed total up to the largest reserves of freshwater outside of the polar regions. The area is the source of 10 major river systems that provide water to almost 2 billion people.
Climate change reports have alerted that warming is not just threatening this supply of water, however also increasing the likelihood of natural dangers ( SN: 5/29/19). In the Intergovernmental Panel on Climate Change’s 2019 special report on oceans and the cryosphere, scientists noted that glacier retreat, melting snow and thawing permafrost are making mountain slopes more unstable and also increasing the variety of glacial lakes, upping the possibility of an unexpected, catastrophic failure ( SN: 9/25/19).
A 2019 thorough evaluation concentrating on climate modification’s impacts in Asia’s high mountains found that the glaciers in the area have pulled away a lot more quickly in the last decade than was anticipated, Prakash states, “which is worrying for us.” Here’s another method to take a look at it: Glaciers are pulling away twice as quick as they were at the end of the 20 th century ( SN: 6/19/19).
Glacier-related landslides in the area have also ended up being significantly typical in the last decade, as the area warms and destabilizing freeze-thaw cycles within the ground occur greater and higher up on the slopes.
However when it comes to this particular disaster, Shugar states, it’s simply hard to say conclusively at this point what role climate modification might have played, or even what specific event may have triggered a landslide. “Sometimes there is no trigger; often it’s simply time,” he says. “Or it’s that we just don’t comprehend the trigger.”
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