16 / 2025-07-09 09:55:00

Dynamic modeling of rock-ice-snow avalanche disaster chains

Rock-ice-snow avalanche,Disaster chain,Numerical modeling

In the context of global climate change, rock-ice and snow avalanches pose an increasing threat to infrastructure and communities in high-altitude regions worldwide. These avalanches are characterized by high mobility, long runout and strong destructive force. Predicting their destructive potential is essential for disaster mitigation and has socio-economic significance.

During the rapid downslope movement, the rock-ice and snow avalanches often interact violently with the ambient air, generating powerful air blasts that can cause destruction far beyond the runout area. Simultaneously, the basal shearing and particle collision lead to the progressive melting of ice and snow. The resulting increase in meltwater content can lead to a transition in flow regime, transforming the event into a highly mobile, water-rich debris avalanche or even a debris flow.

Given the multiphase nature and phase transitions inherent in such mass flows, there is a pressing need for specialized dynamic models that can capture their evolution and associated risks. In this study, we present a novel dynamic model for rock-ice-snow avalanches, RAMMS::ROCKICE (Zhuang et al., 2023, 2024), developed based on a two-layer structure and depth-averaged theory. The model incorporates the conservation of mass, momentum, and energy, enabling efficient tracking of ice/snow–water phase transitions, associated changes in flow regime, and the generation of air blasts. We apply this model to two representative events in the Himalayas-the Chamoli rock-ice avalanche-debris flow and the Langtang rock-ice-snow avalanche-air blasts. The simulations successfully reproduce the dynamic processes of these catastrophic events. Our findings provide new insights into the dynamics of rock-ice-snow avalanches and offer a robust tool to support risk assessment in glaciated regions such as Tibet.