What caused the Glacial Lake Outburst in Uttarakhand?

A part of the Nanda Devi glacier at Joshimath in Chamoli district of Uttarakhand bursted on February 7, 2021 causing the death of at least 18 with more than 150 people missing. Environmentalists claim that the glacier bursted due to changes in the climate.

“There is no doubt that global warming has resulted in the warming of the region. Climate change-driven erratic weather patterns like increased snowfall and rainfall, and warmer winters have led to the melting point of a lot of snow falling. The thermal profile of ice is increasing…. where earlier the temperature of ice ranged from minus six to minus 20 degree Celsius, it is now minus two, making it more susceptible to melting,”
– IANS quoted Mohd. Farooq Azam, an Assistant Professor at IIT Indore
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As per Farooq Azam, no glacial lake was visible in Google Earth images and there might be a probability of existence of a water pocket or lake inside the glacier.

“The IPCC’s Special Report on Oceans and Cryosphere in a Changing Climate reports that climate change has altered the frequency and magnitude of natural hazards. The scientists reported with medium confidence that in some regions, snow avalanches involving wet snow have increased, while the rain on snow floods have also increased at lower elevations in springs,”
– Anjal Prakash, Research Director and Adjunct Associate Professor at the Indian School of Business in Hyderabad
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The outburst of the glacier in Chamoli district led to an increase in the water level in the Alaknanda river system which in turn washed away hydroelectric stations.