Los Angeles, US, Jun 10 (EFE).- A large wedge of rock that broke off a steep Himalayan ridge and took with it glacier ice that melted on its descent was the cause of the disaster that in February killed at least 45 people and left about 200 missing in the Uttarakhand region in India.
A coalition of 53 scientists led by the Universities of Washington and Calgary published the results of their research in the journal Science on Thursday, ruling out the option that a natural overflow of a river or lake caused the tragedy.
The researchers used satellite imagery, seismic records, and eyewitness videos to recreate computer models of the landslide flow.
“We hope that lessons learned from this effort will improve our ability to respond to future disasters and guide policy decisions that will save lives,” said co-author David Shean, a University of Washington assistant professor of civil and environmental engineering.
Initial hypotheses suggested the overflow of a glacial lake, but there are no glacial lakes large enough to produce a flood, the team determined.
“As the block fell, most of the glacier ice melted within minutes. This resulted in a huge volume of water associated with the flooding,” said co-author Shashank Bhushan, a UW doctoral student in civil and environmental engineering.
“This is highly unusual – a normal rock landslide or snow/ice avalanche could not have produced such huge volumes of water.”
Videos filmed with mobile phones of the moment of the avalanche and disseminated on social media networks showed the sudden appearance of a large column of mud and water through the bed of a river, hitting the slopes of the valley with force.
This mountainous region in the Himalayas also recorded floods, landslides and the collapse of buildings in June 2013 after the monsoon rains came a month earlier with rainfall that was 68 percent stronger than usual.
That tragedy caused about 7,000 deaths or disappearances, many of them Hindu pilgrims who had arrived in Uttarakhand to visit some of the most important religious sites, and where the sacred river Ganges is also born. EFE