Impacts of snow avalanches on critical infrastructure under a warming climate: a case study from southeastern Tibet

Avalanches pose significant threats to mountain residents and infrastructure. This study employs the AVALANCHE module of the Rapid Mass Movements Simulation model to simulate avalanche dynamics and deposition patterns and examine associated climatic conditions. An avalanche event in southeastern Tibet on 21 April 2023 is used as a case study. The simulated avalanche reached a maximum flow height of 5.3 m， a peak dynamic pressure of 195 kPa， and a maximum velocity of 38 m/s. The simulated deposition extent was consistent with the field constraint used in back-analysis， while deposit thicknesses and tower-impact pressures showed reasonable agreement with independent field observations and engineering evidence. Sensitivity analysis indicated that basal friction primarily controls runout and deposition， release depth strongly influences avalanche magnitude， and turbulent friction mainly affects velocity-dependent resistance and dynamic pressure. The study further evaluates the effects of splitting wedge location， length and orientation on avalanche flow redirection and tower protection. The optimized V-shaped splitting wedge effectively redirects avalanche flow and reduces dynamic loading on the tower. Climatic analysis indicates that antecedent snowfall followed by rapid warming likely contributed to avalanche instability. These findings support avalanche hazard mitigation and resilient infrastructure design in climate-sensitive high-mountain regions.