3-3-3-3-3-3-3-3-3-3-3-3-3 From: fabiodioguardi@xxxxxxxxx Dear community, We would like to invite you to contribute to Session NH2.1 "*Multidisciplinary Efforts in Understanding Volcanic Processes, and in Quantifying Volcanic Hazard and Environmental Impact*" at the next EGU2025 conference in Vienna (27 April - 2 May 2025). The abstract submission deadline is 13:00 CET, 15 January 2025. *Volcanoes are complex systems capable to cause catastrophic impacts. Understanding, modelling and forecasting volcanic hazards is challenging because they encompass a wide range of processes from grain to flow scales, whose complexity often require a multidisciplinary approach to quantitatively model them. In fact, there is always a need for the development of robust and reliable models for forecasting volcanic hazards, both syn- and post-eruptive.Syn-eruptive hazards include gravity-driven flows (e.g., pyroclastic density currents, rock avalanches), volcanic plumes and gas emission and dispersion, which can all be theoretically described by computational fluid dynamics, and experimentally modelled. But application of experimental and numerical modelling results to large-scale natural processes is often not straightforward due to scaling issues and simplifications of the modelled systems.Uncertainty management is a central issue in volcanic hazard analyses and a plethora of statistical methods have attempted to quantify uncertainty in both hazard modelling and eruption forecasting. The data underlying models for both eruption occurrence and hazard propagation are multi-scale, multi-dimensional and nonlinearly correlated, and often not representative of the volcano's potential behaviour. Additional knowledge is often required to manage causal links, and to extrapolate outside of the perceived bounds of existing data.Post-eruption, understanding the origin, transport and emplacement mechanisms of volcanic deposits is fundamental for accurately reconstructing accumulation histories of ancient and modern volcano-sedimentary records, thus helping to assess future hazards and their potential economic impacts. Many knowledge gaps in these records could be reduced by bringing together multidisciplinary specialists and methods, combining classical field-based work with novel laboratory modelling approaches.The session aims at advancing volcanic hazard estimation and response through multidisciplinary approaches, including:â?¢ A better description of uncertainty in volcanic hazard estimates through the use of statistical, analogue, surrogate and synthetic data,â?¢ Field studies of volcanoclastic features in sedimentary records,â?¢ Analysis of the short- and long-term downstream effects of volcanic events on active landscapes (landslides, lahars, re-sedimentation, flooding etc.).â?¢ New developments in statistical, experimental and computational modelling.* Thanks! Fabio Dioguardi, Melody Whitehead, Alexis Bougouin, Jacopo Selva, Mark Bebbington 3-3-3-3-3-3-3-3-3-3-3-3-3 ------------------------------