Assessment of Avalanche Dynamics of the 2014 Everest Serac Fall Using GIS Hazard Mapping and RAMMS Simulation

Abstract

Abstract

Avalanches pose a persistent and deadly hazard in high-mountain terrain, where steep topography, dynamic snowpack conditions, and rapid cryospheric change converge to generate extreme mass-movement events. The 2014 serac fall on the western shoulder of Mount Everest, which killed 16 Sherpa guides in the Khumbu Icefall, represents one of the most lethal single avalanche incidents recorded in Himalayan mountaineering history, yet its physical dynamics have not previously been analyzed through numerical simulation. This study presents an integrated assessment of avalanche hazards in the Upper Dudh Koshi Basin (Everest region, Nepal) by combining a GIS-based multi-criteria decision analysis (MCDA) using the Analytical Hierarchy Process (AHP) for regional susceptibility mapping with the Rapid Mass Movement Simulation (RAMMS) model for event-specific dynamic reconstruction. Seven terrain and climatic parameters, including slope, elevation, aspect, curvature, land cover, temperature, and precipitation, were derived from satellite and gridded climate datasets, reclassified into hazard levels, and combined through AHP- weighted overlay analysis to produce a five-class susceptibility map. The susceptibility mapping indicates that approximately 34% of the study area falls within the high to very high hazard categories, with the standard Everest climbing route traversing zones classified as very high risk throughout the Khumbu Icefall. RAMMS simulation of the 2014 event yielded a maximum flow height of approximately 35 m, a peak velocity of 36.2 m/s, and localized impact pressures exceeding 1,180 kPa. These modeled dynamics correspond closely with the spatial extent documented by post-event satellite imagery and with accounts from experienced mountaineers who validated the hazard map by independently locating observed avalanche source zones. The results illustrate the utility of this combined GIS-RAMMS framework for hazard assessment in data-scarce, high-alpine environments and suggest practical applications for route safety planning and evidence-based risk governance in Himalayan mountaineering.