Global Volcanic Simulator Assessment of Multiple Hazards of Cities on Volcanoes

Simulatore Vulcanico Globale valutazione di molteplici pericoli delle città sui vulcani

Flavio Dobran, GVES, Naples (Italy)

Useful multi-hazard assessment of cities on active volcanoes requires the utilization of appropriate tools. These hazards should be assessed with different volcanic eruption scenarios that depend on chemical compositions, storage and feeding characteristics of magmas within the volcanos, structures of volcanic edifices that may contain a variety of different fractured systems and aquifers, and conditions of built environments on the slopes of the volcanos. The historical records of eruptions for cities on volcanoes are incomplete because they are subject to different interpretations of eruption dynamics and can be biased (as in the densely populated Neapolitan area) because of the built environments that are hiding some or most of these records.

Building resilient cities on volcanoes is therefore a complex undertaking where the assessment of volcanic eruption scenarios must be performed by the tools that can reliably simulate complete eruptions. Global Volcanic Simulator (Dobran, 1993, 1994) is a tool that can accomplish this task and is continuously being verified and validated to ensure its usefulness. This simulator numerically solves the multidimensional forms of multicomponent and multiphase mass, momentum, energy, and entropy transport equations for each characteristic part of the volcanic complex (magma chamber, volcanic conduit, surroundings of conduit and magma chamber, environment above the volcanic edifice) with the appropriate constitutive equations that best describe the material response (thermo-fluid and elasto-plastic deformations) of each part (Dobran, 1992, 2001, 2006). The simulator determines the relevant equations to be solved for each characteristic part and provides the coupling conditions between different parts (GVES, 2017).

Global Volcanic Simulator has been used to simulate 30,000 years of magma discharge from Vesuvius, magma ascent in volcanic conduits, and dispersions of volcanic products in the atmosphere and propagations of pyroclastic flows on the slopes of several volcanoes. The pyroclastic flow propagation phase is one of the most hazardous scenarios of an explosive volcanic eruption because it can greatly affect the nearby area surrounding the volcanic vent. Within this exclusion area all human habitats should be prohibited and beyond this area the built environment should be made resilient (Dobran, 2018). Mapping of exclusion areas of cities on volcanoes is the first step for making these cities resilient and sustainable.

References

Dobran, F. Theory of Structured Multiphase Mixtures. Springer, New York (1992).

Dobran, F., Modeling of structured multiphase mixtures. Int. J. Eng. Sci., 30 (10) 1497-1505 (1992).

Dobran, F. Global Volcanic Simulation of Vesuvius. Giardini, Pisa (1993).

Dobran, F. Prospects for the global volcanic simulation of Vesuvius. Accademia Nazionale Dei Lincei, Atti dei Convegni Lincei 112, Rome, 197-209 (1994).

Dobran, F. Volcanic Processes: Mechanisms in Material Transport. Kluwer Academic/Plenum Publishers (Springer), New York (2001).

Dobran, F., Ramos, J.I. Global Volcanic Simulation: Physical modeling, numerics, and computer implementation. In F. Dobran (ed), VESUVIUS: Education, Security and Prosperity, 311-372. Elsevier, New York (2006).

Global Volcanic Simulator Manual: Edition 2017. GVES, Naples (2017).

Dobran, F. VESUVIUS-CAMPIFLEGREI PENTALOGUE. International Conference on Resilience and Sustainability of Cities in Hazardous Environments, 26-30 November 2018, Naples, Italy (2018).