Tadini A., A. Harris, J. Morin, A. Bevilacqua, A. Peltier, W. Aspinall, S. Ciolli, P. Bachèlery, B. Bernard, J. Biren, A. Brum da Silveira, V. Cayol, O. Chevrel, D. Coppola, H. Dietterich, A. Donovan, O. Dorado, S. Drenne, O. Dupéré, L. Gurioli, S. Kolzenburg, J.C. Komorowski, P. Labazuy, D. Mangione, S. Mannini, F. Martel-Asselin, E. Médard, S. Pailot-Bonnétat, V. Rafflin, M. Ramsey, N. Richter, S. Vallejo, N. Villeneuve, and S. Zafrilla (2022).
Volcanica, 5(1), 105–131. doi: 10.30909/vol.05.01.105131

Abstract

Formalised elicitation of expert judgements has been used in recent years to help tackle several problematic societalissues, including volcanic crises and pandemic threats. We present an expert elicitation exercise for Piton de laFournaise volcano, La Réunion island, held remotely in April 2021. This involved twenty-eight experts from ninecountries who considered a hypothetical effusive eruption crisis involving a new vent opening in a high-risk area.The tele-elicitation presented several challenges, but is a promising and workable option for application to futurevolcanic crises. Our exercise considered an “uncommon” eruptive scenario with a vent outside the present calderaand within inhabited areas, and provided uncertainty ranges for several hazard-related questions for such a scenario(e.g. probability of eruption within a defined timeframe; elapsed time until lava flow reaches a critical location, andother hazard management issues). Our exercise indicated that such a scenario would probably present very differentcharacteristics than the eruptions observed in recent decades, and that it is fundamental to include well preparedexpert elicitations in updated civil protection evacuation plans to improve disaster response procedures.