Weathering, tectonics, gravitational and volcanic processes can transform the regular sediment delivery from unstable slopes in catastrophic landslides. Mass spreading and mass wasting processes can potentially evolve in rapid landslides are among the most dangerous natural hazards that threaten people and infrastructures, directly or through secondary events like tsunamis.

Documentation and monitoring of these phenomena requires the adoption of a variety of methods. The difficulties in detecting their initiation and propagation have progressively prompted research into a wide variety of monitoring technologies. Nowadays, the combination of distributed sensor networks and remote sensing techniques represents a unique opportunity to gather direct observations. A growing number of scientists with diverse backgrounds are dealing with the monitoring of processes ranging from volcano flak deformations to large debris flows and lahars. However, there is a need of improving quality and quantity of both documentation procedures and instrumental observations that would provide knowledge for more accurate hazard assessment, land-use planning and design of mitigation measures, including early warning systems. Successful strategies for hazard assessment and risk reduction would imply integrated methodology for instability detection, modeling and forecasting. Nevertheless, only few studies exist to date in which numerical modelling integrate geological, geophysical, geodetic studies with the aim of understanding and managing of terrestrial and subaqueous volcano slope instability.

Scientists working in the fields of hazard mapping, modelling, monitoring and early warning are invited to present their recent advancements in research and feedback from practitioners and decision makers. We encourage multidisciplinary contributions that integrate field-based on-shore and submarine studies (geological, geochemical), geomorphological mapping and account collection, with advanced techniques, as remote sensing data analysis, geophysical investigations, ground-based monitoring systems, and numerical and analogical modelling of volcano spreading, slope stability and debris flows.