A new scientific study has warned that ice avalanches from hanging glaciers above Badrinath Township in the central Himalayas could expose hundreds of buildings and key infrastructure to danger, and has urged authorities to act early.
Favourable channel shape and downstream terrain can keep an avalanche moving even when the amount of ice released is comparatively smaller. Researchers used remote-sensing data and model-based methods to estimate where ice could break off and how much of it might fall. They then used the Rapid Mass Movement Simulation (RAMMS) model to show how such avalanches might travel downhill. The scientists ran the simulations under low, medium and high mobility conditions by changing the friction values within ranges based on terrain and elevation. Larger release volumes and steeper slopes generally led to stronger flow and longer runout. The high-mobility condition consistently produced the most severe results. However, the gap between the low and high conditions was fairly small. The study also makes an important point about how avalanches behave.
The research, titled “Vulnerability assessment of hanging-glacier avalanches in Badrinath Township, Central Himalayas, India”, looked at three hanging glacier sites surrounding the holy town. The study says flow behaviour was “primarily influenced by release volume, glacier slope, and downstream terrain”. The shift from low to high mobility changed maximum height by “2.3 to 6.7 per cent”, pressure by “2.9 to 3.8 per cent”, deposition by “0.9 to 7.4 per cent” and velocity by “1.3 to 1.8 per cent” across the three sites, according to the study. It notes that runout “is not controlled solely by release volume”.
