Natural hazards rarely occur independently. Earthquakes can trigger landslides, landslides can dam rivers and generate floods, volcanic eruptions can induce mass movements and tsunamis, wildfires can alter hydrological and sediment transport processes, and changes in glaciers and permafrost can initiate sequences of slope failure, debris flow, and flooding. In such cascades, an initial process modifies the physical state of the system and controls the initiation, magnitude, timing, or propagation of subsequent hazards. Risk evolves with these cascades, as exposure and vulnerability are reshaped by each successive event. Damaged infrastructure, depleted response capacity, displaced populations, and altered land use can amplify the consequences of later hazards, so that dynamic vulnerability becomes a first-order control on cascading risk.
Despite increasing attention to multi-hazard risk, the mechanisms governing these interactions remain poorly understood. Key questions concern how energy, mass, water, sediment, and stress are transferred between processes; how these processes interact; how antecedent conditions and event history influence subsequent hazards; and how feedbacks, nonlinearities, and differences in spatial and temporal scales control whether a disturbance attenuates or develops into a cascade. Answering these questions requires long-term observations to capture the slow preconditioning, relaxation, and recovery phases that link successive events, and allow rare but high-impact cascades to be placed in a meaningful statistical and process-based context.
This session brings together research on the physical processes governing cascading natural hazards. We welcome observational, experimental, theoretical, numerical, and data driven studies addressing topics including:
•Multiphysics modelling of triggering, coupling, amplification, and attenuation between hazard processes;
•Transfer of mass, momentum, energy, stress, water, and sediment between interacting processes;
•Reconstruction and analysis of well documented cascading events across different environments and spatial and temporal scales.
•Field observations, Earth observation, geodetic, seismological, hydrological monitoring, and other measurements used to resolve process interactions;
•Methods for identifying causal relationships and separating triggering from coincident or common forcing;
•Effects of environmental and climatic change on the physical conditions controlling hazard cascades;