A recent study by ISRO scientists revealed that Dharali village (Uttarakhand) 2025 flash flood was not triggered by a cloudburst or a Glacial Lake Outburst Flood (GLOF), but by the sudden collapse of an exposed ice patch.

• This ice patch was located within the nivation zone of the Srikanta Glacier.
• Nivation: It is the progressive erosion of the ground beneath and around a snowbank, primarily driven by alternate freeze-thaw cycles.

Causes of increase in Himalayan disasters

• Climate Change: Accelerated glacier thinning, altered precipitation, and rising temperatures reduce the insulating seasonal snow cover that typically protects underlying ice.
• Thermal & Mechanical Destabilization: Exposed ice responds rapidly to temperature fluctuations and minor perturbations, making it highly susceptible to melting, fragmentation, and sudden gravitational collapse.

Effects of Deglaciation in Himalayas

• Cascading Cryo-Hydrological Hazards: The sudden release of fragmented ice, meltwater, and entrained debris can create short-duration, high-velocity surges.
• Topographic Amplification: In steep, confined Himalayan valleys, even a small volume of collapsed ice translates into massive gravitational potential energy, producing highly erosive, debris-laden floods.
• Socio-Economic Destruction: These multiphase hazards lead to massive channel widening, structural destruction of settlements, and threats to religious transit hubs, lowland communities, and hydropower security.