A devastating flood disaster is waiting to happen in Sikkim! If only one will awaken to it.
Analysis of satellite data has revealed that the lake has formed at the snout of South Lhonak glacier, that is about 7,000 metres high on the mountain in the northeastern state. The lake, bounded by loose soil and debris, could cause havoc downstream if it ruptures, according to scientists at the National Remote Sensing Centre (NRSC) in Hyderabad.
The lake is 630 metres wide and 20 metres deep and is over an area of 98.7 hectares containing 19.7 billion litres of water! The scientists added that the probability of this happening was very high. Actually, the South Lhonak glacier has receded almost 2 km back since 1962. Information and images from American Landsat, CORONA and Terra satellites and India’s own Resourcesat-1 satellite were used to determine the impact of Climate change. In 1962 it was a small water body, but as the glacier melted, it kept on adding to the water of the lake. Over the years, the water will only increase as the glacier melts away, making this a veritable ticking time bomb!
It is anybody’s guess if the Government of Sikkim or India plan and do something to mitigate a sure disaster waiting to happen?
Sad thing is that this is not the only glacier lake forming in Sikkim, there are several others. Global Warming can be devastating to Himalayan states over the years.
Changsang Glacier is a valley glacier just north of Kanchengjunga, the third highest peak, in Sikkim. A comparison of Landsat imagery from 1989 to 2012 identifies the formation of a lake at the end of the glacier. The red arrow indicates the downvalley end of the lake that will develop, the green arrow the upvalley end. In 1989 there is no evidence of a lake either on top of the glacier, supraglacial or proglacial, at the end of the glacier. In 2000 there are a several small lakes beginning to develop. In the 2006 Google Earth imagery the lake is 700 meters long with several other developing smaller lakes. By 2011 the main lake is 1000 meters long and has one debris covered ridge that separates it from a second lake. By 2012 the lake has expanded incorporated the second lake and is now 1500 meters long. The Changsang Glacier was reported to be retreating 22 m/year from 1976 to 2005 (Raina, 2009). In Sikkim 26 glaciers examined were retreating at an average rate of 13.02 m per year from 1976 to 2005 (Raina, 2009) is following the same path as South Lhonak Glacier just to the north and Zemu Glacier just to the south. Zemu Glacier to the south is fed by a higher accumulation zone, and has not been retreating as fast, but it should be anticipated that a lake will form near its terminus.
With 3 glacier lakes forming, something needs to be done about this region like yesterday! If the devastation by these lakes cannot be mitigated, then the entire population from this region should be moved out.