Devastating flash floods hit the northeastern state of Sikkim on Wednesday, 5 October, with at least 14 people dead and over 100 more missing.
But what exactly triggered the floods? The National Remote Sensing Centre, a unit of the Indian Space Research Organisation (ISRO), conducted a satellite-based study on the 'Outburst of the South Lhonak Lake' in Sikkim.
The study was conducted on the basis of before-and-after images which shows that the South Lhonak Lake was drained of vast volumes of water that flowed downstream into the Teesta River, and in turn, flooded low-lying areas.
Here's what the ISRO study reveals.
"It is observed that Lake is Burst and about 105 Hectares area has been drained out (28 September 2023 image versus 04 October 2023) which might have created a flash flood downstream," ISRO wrote on its website.
The country's space agency added that it will continue monitoring the lake by further using satellite data.
'A Combination of Rainfall & GLOF': NDMA
Meanwhile, the National Disaster Management Authority (NDMA) has also provided a brief explanation: "In the early hours of Wednesday, there was a sudden surge in water flow in the Teesta river, which washed away several bridges, parts of NH-10, the Chungthang Dam and has impacted several small villages, towns and infrastructure projects in the upper reaches of the river valley."
"The primary reason for sudden surge appears to be a likely combination of excess rainfall and the Glacial Lake Outburst Flood (GLOF) event at the South Lhonak Lake in North Sikkim," it added.
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