Uttarakhand flash floods: Glaciers in Himalayas retreating due to climate change, says GSI DG

Uttarakhand Glacial Burst: A glacier burst in the Tapovan-Reni region of Uttarakhand’s Chamoli district shook the country on Sunday, as the Alakananda and Dhauli Ganga rivers became flooded. The houses near the rivers were heavily damaged and so was the Rishiganga power project, where about 100 workers were deployed, and of them, some of them are feared dead. The glacier burst, however, has left scientists all over the country wondering what exactly happened that caused this event. Amid this, the Director General of Geological Survey of India, Dr Ranjit Rath said that the glaciers in the Himalayas were retreating due to the climate change.

Adding that this was happening at a global scale, he said that as time passed, sometimes glacier lakes near terminus coalesced together to form large glacial lakes which were dammed by a mixture of loose boulders, sand, and gravels containing dead ice, called glacial moraines. These moraines, due to the composition, were weak.

He added that such lakes were very common on Himalayan glaciers, and the outbursts like the one in Uttarakhand, called Glacial Lake Outburst Flood (GLOF), resulted in a huge volume of water being discharged, damaging areas falling in the downstream.

He further said that the breach in the glacial lake can be triggered by a lot of things like an avalanche or a landslide in the lake’s periphery, a cloudburst in catchment, snout’s calving, piping in the moraine dam, or a strong earthquake.

Rath added that after the Kedarnath cloudburst tragedy of 2013 that struck the state, the creation of an inventory of glacial lakes in the Uttarakhand Himalayas began in 2014, in order to identify the GLOF high-risk areas and the exercise was concluded in 2016. The remote sensing and multi-spectral data was analysed and it was found that excluding the supra-glacial lakes, the state had 486 glacial lakes, of which 13 were found to be vulnerable.

Meanwhile, more than 200 people have gone missing in these floods and rescue operations are underway.