Levan Tielidze, Monash University and Digital Storytelling Team, The Conversation
On August 26 a glacier collapsed in the Langtang region of Nepal near the China border, triggering an ice and rock avalanche. This apparently entered the Lhende Khola, a tributary of the Bhote Koshi river, where it either caused or contributed to a temporary blockage. When this burst, a catastrophic flash flood travelled almost 100 kilometres downstream.
A glacier collapses
There’s nothing to stop the avalanche down the Trishuli river valley
Did warm conditions play a role?
There is increasing interest in the role of unusually warm conditions and glacial permafrost instability. Warming can increase meltwater penetration into the crevasses of glaciers and weaken ice-rock bonds. British Antarctic Survey researchers reported unusually high ground temperatures two days before the collapse.
Satellite images stitched from Copernicus Sentinel-2 data
Video sources: Gyirong Port – AP News_; Boulder – ABC News; Fast moving water – @pujanpokhareofficial/Instagram
You can support the Nepal Flood Disaster Appeal through the Emergency Action Alliance website or by calling 1300 939 000.
Levan Tielidze, Research Fellow in Glacial Geomorphology, Monash University and Digital Storytelling Team, The Conversation
This article is republished from The Conversation under a Creative Commons license. Read the original article (https://theconversation.com/satellite-images-show-how-the-nepal-flood-disaster-unfolded-290721).
Featured image credit: ABC/Instagram
