In conversation with International Innovation, Drs Amanda NERI & AUGUSTO DRS AMANDACLARKE Clarke and Augusto Neri Explosive describe their successful international collaborative research programme on work exploding volcanoes

Flavio Dobran and Dr Giovanni Macedonio, aimed collaborations, such as the special and long- at simulation of volcanic processes. This was lasting cooperations with Professor Barry Voight, then a very innovative approach that recognised Amanda and Dr Christina Widiwijayanti on the the need to complement field observations with modelling and simulation of magma ascent and quantitative representations based on the laws explosive events at Mount St Helens and Soufriere of physics and modern mathematics. Explosive Hills volcanoes. volcanism was a key subject for us due to the fact that in Italy we have very-high-risk explosive What do you consider to be your team’s major volcanoes such as Vesuvius and Campi Flegrei. I contributions up to now? was also fascinated by the challenging and always surprising beauty of these phenomena, and wished AN: I would say that perhaps the most important to contribute to mitigating their hazards. contribution of our INGV research team, which includes Amanda as Research Associate, has been Could you discuss your accomplishments and the demonstration of the genuine value that The INGV research group (from left to right): Augusto your hopes for the far-reaching impact of physical and mathematical models can provide Neri, Mattia de’Michieli Vitturi, Amanda Clarke, Sara your work? for a deeper understanding of volcanic processes. Barsotti and Tomaso Esposti Ongaro. Very often the complexity of these nonlinear and AC: Like Augusto, a key goal of my work has often non-observable processes prevents a simple Dr Clarke, could you begin with some remarks been to combine mathematical models with interpretation of the dynamics, and therefore on your background and what attracted you to relevant field observations and data in order to mathematical models are required to quantitatively explosive volcanism research? better understand the physics of, and controlling describe the relationships between the variables factors in, important eruptions of the past. The that control the system. Our research work has AC: Certainly! My undergraduate degrees at purpose has been to illuminate the key processes also had a significant impact in the assessment of the are in Aerospace and demonstrate the effectiveness of a particular volcanic hazards. With the 2D and 3D modelling and Mechanical Engineering, and Philosophy. model in simulating real volcanic eruptions. technology we developed at INGV, time-varying My interest in volcanic eruptions began while We have been fortunate in achieving some numerical simulations of plausible future explosive interning at the Boeing Company, when I became success, for instance in understanding the role events – at Vesuvius and for instance – aware of an incident involving the loss of four of dynamic pressure in producing damage in a have proven extremely useful to represent the likely engines on a 747 airliner that had interacted pyroclastic current, and in partnership with INGV dynamics of eruption and identify areas at risk. with a volcanic ash cloud. Several years later in describing the physics in great detail inside an I began a PhD in Geosciences at Pennsylvania otherwise opaque eruption plume, and also the Do you play an active role in nurturing the State University working under Professor Barry physics of lava-dome eruptions. development of the next generation of Voight, with my main research focused on researchers in the field? solving problems in explosive volcanism using Who makes up your collaborative modern numerical fluid dynamics. As part of this research team? AC: Yes, I am very proud of my PhD students, research I also assisted the volcano observatory and several of them have become quite in Montserrat during the summer of 1997, and AN: In my activity I have tried as much as possible successful. Brittany Brand is now an assistant had the good fortune of witnessing a series of to attract bright young researchers that can professor at Boise State University, Kimberly spectacular hazardous explosions. Not long contribute to the development of our modelling Genareau is an assistant professor at the afterward this study triggered the possibility approach. I have been lucky to find special PhD University of Alabama and Kirsten Chojnicki is a of collaboration with Augusto at the Istituto students that are now leading the advancement postdoc at Scripps Institution of Oceanography. Nazionale di Geofisica e Vulcanologia (INGV). of this field at the international level. In particular One of my goals in mentoring PhD students Tomaso Esposti Ongaro, Mattia de’Michieli Vitturi is to ensure they will have made a unique Dr Neri, how did your interest and efforts in and Sara Barsotti. Tomaso is based in INGV, Mattia contribution to the field of and this area begin? shares his time between INGV and Arizona State have built a strong, effective research skillset. University (ASU) working with Amanda, and Sara This will help them to stand out in the research AN: My background is in chemical engineering, so I is currently Head of the volcanic hazard section community. Our ASU group has also been started out similarly to Amanda. After my Master’s at the Icelandic Meteorological Office, currently well supported by visitor research, including my interest was piqued by a new and ambitious dealing with the Bardarbunga eruption. A further Mattia, and others such as the Russian field project starting at INGV with the support of paramount contribution to the development volcanologists Drs Marina and Sasha Belousov, Professor Franco Barberi and the leads of Professor of our research team comes from international and UK scale-modeller Dr Jeremy Phillips. WWW.INTERNATIONALINNOVATION.COM 39 DRS AMANDA CLARKE & AUGUSTO NERI

Challenges in volcanology The study of volcanoes is challenging for a number of reasons, but novel research based at Arizona State University, USA, and the Istituto Nazionale di Geofisica e Vulcanologia, Italy, is overcoming these difficulties using a unique approach that combines a variety of experimental and theoretical methods with broad collaboration and interdisciplinary influences

VOLCANOLOGY IS AN immensely interesting EXAMPLE APPLICATIONS the propagation of the eruptive cloud, made field where the basic sciences of geology and up of high-temperature gases, ash, pumice geophysics encounter profound and readily Volcanic lateral blasts are among the most and rock fragments, over the mountainous understandable human impacts. The scale and spectacular and devastating of natural phenomena region surrounding the volcano, and correctly diversity of volcanic impacts is such that, even but until the recent work of PhD student Tomaso reproduce the flow-front velocity, run-out (the in recent years, disasters at Mount St Helens Esposti Ongaro, Neri, Clarke and colleagues, their maximum distance reached by the cloud) and in the US, in Colombia, the dynamics had not been properly understood. The impact. The team’s results demonstrated that, Soufrière Hills volcano in Montserrat and Iceland’s best documented and most controversial of blasts when detailed geological constraints and high- Eyjafjallajökull have confounded the ability of occurred in a destructive eruption in a forested performance supercomputers are available, those affected to predict or respond effectively wilderness area at Mount St Helens in 1980, physical models can now fairly accurately to them. The practical value of volcanology in which provided the spark for a renaissance in reproduce the main large-scale features of blast assessing volcanic hazards is clear. modern volcanology. By means of 3D multiphase scenarios. Such an improvement in modelling flow numerical simulations, the researchers’ work capability will make it possible to more The field has traditionally relied on mapping of demonstrated that the blast-front propagation, effectively map potential blast flows at blast- past eruptions to estimate the threat from future final run-out and damage can be explained by dangerous volcanoes worldwide. blasts, but following pioneering, collaborative the emplacement of an unsteady, stratified achievements such as those of Drs Amanda pyroclastic density current, controlled by gravity The results are a tribute to the fully 3D transient Clarke and Augusto Neri, based at Arizona State and terrain morphology. multiphase flow code – Pyroclastic Dispersal University (ASU) and the Istituto Nazionale di Analysis Code (PDAC) – recently developed by Geofisica e Vulcanologia (INGV), respectively, 30 years after the 1980 eruption, supercomputer Ongaro and his colleagues at INGV. PDAC utilises volcanologists increasingly rely on numerical and simulations have allowed the team to reproduce the power of supercomputers, with runs using 8 laboratory models to understand the process and and analyse the large-scale features of this blast, million computational cells, and with each run mitigate hazards. which devastated a broad area of 600 km2 north (simulating about 400 s of the real event) taking of the volcano and about 10,000 hours of CPU time, equivalent (at resulted in the deaths that time) to about five days on 128 AMD cores at of 57 people. Initial 2.4 GHz in parallel execution. conditions, triggering the violent explosion NOTORIUS MOUNT VESUVIUS of the magmatic mixture, were derived The INGV team, in cooperation with the from the wide CINECA Supercomputing Center in Bologna, geological dataset applied the simulation model, based on available for this multiphase transport laws, to describe the 4D eruption, which is one (3D spatial coordinates plus time) dynamics of the most studied of explosive eruptions at Mount Vesuvius, and documented in Italy. Numerical experiments, carried out Simulation output at Vesuvius. PDAC multiphase flow model for boiling-over collapse volcanology. on a parallel supercomputer, describe the in a sub-Plinian eruption scenario. a) Isosurfaces of the total volume particle fraction collapse of the volcanic eruption column and corresponding to 10_4 (dark brown), 10_6 (light red) and 10_8 (grey). b) Distribution of The 3D computer the propagation of pyroclastic density currents the total volume particle fraction over a selected vertical plane passing through the vent model was then (PDCs), for selected medium-scale (sub- and over the ground. able to describe Plinian) eruptive scenarios at Vesuvius. 40 INTERNATIONAL INNOVATION INTELLIGENCE SCHOOL OF EARTH AND SPACE EXPLORATION, ARIZONA STATE UNIVERSITY ISTITUTO NAZIONALE DI GEOFISICA E VULCANOLOGIA OBJECTIVES • To combine science and engineering research and education to achieve a better understanding of the Universe • To research and monitor geophysical phenomena, including seismic surveillance, real-time volcanic monitoring and forecast activities FUNDING National Science Foundation (Petrology and The simulations provide crucial insights into the Geochemistry) • E-project EXPLORIS • Italian effects of the generation mechanism of the flows Civil Protection Agency – partial collapse versus boiling-over – on their evolution and hazards potential, the unstable CONTACT dynamics of the fountain, and the topographic Dr Amanda B Clarke influence of the Mount Somma open-sided crater Associate Professor on the propagation of PDCs into the circum- Vesuvian area, one of the world’s most hazardous Arizona State University School of Earth and Space Exploration volcanic settings. The group’s results also show PO Box 871404 that it is possible to characterise the volcanic Tempe, Arizona, 85287-140 column behaviour in terms of percentage of USA the mass of pyroclasts collapsed to the ground, and how this parameter strongly influences the T +1 480 965 6590 dynamics and hazards of the associated PDCs. E [email protected] http://volcanology.asu.edu/faculty.html WORK IN THE DESERT Dr Augusto Neri Research Director of Physical Volcanology At ASU, Clarke leads her lab in investigations of the physics behind explosive volcanism, combining Istituto Nazionale di Geofisica e Vulcanologia numerical modelling and active fieldwork with Sezione di Pisa scaled laboratory experiments to provide an Via della Faggiola 32 exhaustive picture of how volcanoes operate. 3D Computer model of Mount St Helens blast. Total 56126 Pisa, Italy Innovative theoretical research on conduit concentration of pyroclast particles (in logarithmic scale) T +39 050 831 1930 magma flows has been developed with Mattia in the atmosphere. A) Initial position of the exploding E [email protected] source. B) 3D volume-rendering at 380 s (final run time). de’Michieli Vitturi. Also, drawing on her own varied C) 2D rendering along the NE section, superimposed on www.pi.ingv.it educational background Clarke pursues a diverse map at 10 m above the ground level. portfolio of research directions comprising not DR AMANDA B CLARKE studies the nature only volcanic physics, but also eruption prediction and causes of explosive volcanic eruptions, and hazard assessment, volcano deformation and multifarious approach to understanding three with special interest in understanding the even the interpretation of pyroclastic deposits on important factors in the behaviour of short-lived behaviour of multi-phase fluids. She gathers Earth and Mars. eruptions: firstly, the causes and controls of their data about complex natural systems by distinctive timing; secondly, the characteristics observing and monitoring eruptions and The Arizona team brings a number of unique of their jet and plume dynamics; and finally, the performing stratigraphic and sample analysis. methodologies to their work, both inside the lab degassing and integrated gas flux qualities they She uses laboratory experiments and and out, such as particle image velocimetry (PIV) exhibit. The field observations informing this numerical models to gain a general physical understanding of real volcanoes, which which allows observation and measurement of investigation are collected at several volcanoes ultimately aids volcano hazard assessment. velocities within fluid flows that can be created in around the world, including the Soufrière Hills a laboratory environment. PIV works by seeding volcano, and the Semeru volcano and Lumpur DR AUGUSTO NERI is concerned with the a fluid with highly-reflective particles that are Sidoarjo mud volcano, both in Indonesia – all physical-mathematical modelling of volcanic receptive to imaging – in this case, silver-coated active and currently unpredictable threats to the processes, with special focus on atmospheric particles. Then, using laser light cameras, the people and lands surrounding them. dispersal, the formation and propagation scientists can use these particles as reference of pyroclastic flows, ash-fall dispersal and points within the fluid, and thereby measure how deposition and the development of integrated BEING PREPARED fast different parts are flowing – an important models of volcanic systems. He has also contributed to the application of probabilistic question for inhomogeneous, multiphase fluids. Volcanology, especially in the area of explosive techniques to estimate volcanic hazard and eruptions, is a crucial field of research with associated uncertainty, with particular reference More recently, activity in the Clarke lab has focused worldwide impact. History has shown that the to major active volcanoes in Italy and abroad, eg. on persistently active volcanic systems – volcanoes most devastating volcanic events claiming tens Soufrière Hills, Eyjafjallajokull and Santorini. that undergo short-lived and highly impulsive of thousands of lives are those for which local eruptions at semi-regular intervals, and on highly populations have been unprepared – and with explosive basaltic volcanism – an occurrence that their crucial work towards a better understanding is uncommon but therefore intriguing. The team, of explosive volcanic eruptions, Neri, Clarke and including ASU Professor Ron Adrian and Dr Kurt their talented colleagues are helping to ensure Roggensack, has brought its interdisciplinary, that these calamities need not be repeated. WWW.INTERNATIONALINNOVATION.COM 41