28026 - Volcanic Risk

Learning outcomes

At the end of the course, the student learned the basic concepts on the evaluation of volcanic risk mitigation in relation to the hazards for different primary eruptive phenomena (fall processes, pyroclastic currents, lava flows) and secondary (collapses, lahars, tsunamis, landslides), and monitoring systems of the eruptive activity. In particular, the student is able to read and use hazard maps and know the volcanological implications of land planning based on volcanic risk.

Course contents

The course is divided into six parts:

1. Introduction to volcanic risk: definition of the impact of volcanic processes on the territory and society, highlighting the different meanings of the concepts of hazard, risk, and volcanic disaster.

2. Physical Volcanology: definition of the processes underlying volcanic eruptions and the methods used for their characterization. The most recent methodologies useful for reconstructing the tectonic-stratigraphic evolution of a volcanic area and defining the physical-mathematical parameters of eruptions through detailed analysis of the characteristics of the deposits from the eruptions will be illustrated. This approach aims to assess the hazard for fallout deposits (intensity, magnitude, critical mass load), pyroclastic flow deposits (dynamic pressure, flow-front velocity e slip velocity), lava flows, lahars (hydrodynamic pressure), and debris avalanches.

3. Volcanic monitoring: the precursor signals of an eruption are linked to the movements of fluids, magma, and vapor within a volcano and its feeding systems; these precursor signals can be detected by an adequate monitoring program. Different techniques of geophysical, geodetic, and geochemical monitoring (both in situ and remote sensing) will be illustrated, useful for measuring seismic, soil deformation, and gas species variation that characterize the transition from a state of quiescence to one of unrest in an active volcano.

4. Volcanic eruption forecasting: starting from the data synthesis of physical volcanology and monitoring for the development of hazard maps (based on geological, probabilistic bases, etc.), related to different volcanic phenomena that characterize the progress of eruptions, different methodological paths for long-term (forecast) and short-term (prediction) eruption forecasting will be illustrated. The success of forecasting different volcanic events depends on: a) the accuracy of the reconstruction of the eruptive history of the volcano and its internal structure, as well as the potential eruption trigger mechanisms from past eruptions; b) the precision of the monitoring network in detecting any changes in the standard behavior of the volcano during the transition from a state of quiescence to one of unrest. Examples of recent eruptions where forecasting has been effective (Mount St. Helens 1980, Pinatubo 1991, etc.) or ineffective (La Soufrière 1974, Mount Pelée 1902, Nevado de Ruiz, etc.) will be presented.

5. Mitigation and management of volcanic risk: the most effective practices for developing targeted actions for systematic development and the application of policies, strategies, and practices to minimize vulnerability and disasters by prevention and/or limiting (mitigation and preparation) the damage caused by volcanic eruptions will be illustrated, in order to promote sustainable development.

6. Impact of volcanic eruptions on ecosystems: analysis of how volcanic eruptions have an impact at both regional and global levels due to climatic disturbances, ash dispersion in the atmosphere, and perturbations in air traffic. The ecological consequences of volcanic ash, which can disrupt trophic chains even thousands of kilometers away from the volcano, will be highlighted. Special emphasis will be placed on marine and coastal ecosystems, with specific reference to the impact of tephra dispersion during eruptions of great magnitude.

Excursions to Vesuvius and the Phlegraean Fields: the course will be completed by an excursion to Vesuvius and the Phlegraean Fields, with a visit to the monitoring center of the Vesuvius Observatory (INGV), or alternatively, the Aeolian Islands.

Readings/Bibliography

· Lecture notes.

· J. Martì & G.G.J. Ernst. Volcanoes and the Environment. Cambridge University Press, 2005.

· S.A. Fagents, T.K.P. Gregg, R.M.C Lopes. Modelling volcanic processes.The physics and mathematics of volcanism. Cambridge University Press, 2013.

· H. Sigurdsson. Encyclopedia of Volcanoes. Accademic press, San Diego, U.S.A., Second edition, 2015.

· P. Papale. Volcanic hazards, risks and disasters. Elsevier, 2015.

· P. Papale Forecasting and Planning for Volcanic Hazards, Risks, and Disasters. Elsevier, 2021.

Teaching methods

Class lectures performed by adopting up-to-date techniques in didactics (e.g. powerpoint and keynote presentations). Use of original iconographic stuff (outcrop photos) depicting volcanic structures and deposits which have been treated during the lessons on theory. The course will end with a field event in which the students will examine the deposits related to the high hazard eruptions of Vesuvius and Phlegrean Fields.

Assessment methods

The final test will be carried out through a multiple-choice or oral examination aimed at verifying of the student's theoretical knowledge in risk assessment and mitigation, together with the ability to correlate theoretical knowledge and field observation data.

Teaching tools

Keynote and powerpoint presentations

Links to further information

https://www.unibo.it/sitoweb/claudio.tranne/

Office hours

See the website of Claudio Antonio Tranne

See the website of Federico Lucchi