Seismo-acoustic characterization of the 2019 Stromboli volcano paroxysm events

Author(s):  
Alexis Le Pichon ◽  
Emanuele Marchetti ◽  
Christoph Pilger ◽  
Lars Ceranna ◽  
Viviane Souty ◽  
...  

<p>Stromboli volcano is well known for its persistent explosive activity, with hundreds of explosions every day ejecting ash and scoria up to heights of several tens/few hundreds of meters. Such a mild activity is however punctuated by lava flows and major/paroxysmal explosions, that represent a much larger hazard. On July 3rd and August 28th 2019, two paroxysmal explosions occurred at Stromboli, generating an eruptive column that quickly raised up to 5 km above the sea level. The Toulouse Volcanic Ash Advisory Center (VAAC) emitted an advisory to the civil aviation with a two-hour delay. The various processes of this event were monitored near and far field by infrasonic arrays up to distance of 3,500 km and by the Italian national seismic network at range of hundreds of kilometres. Using state-of-the-art propagation modeling, we aim at identifying the various seismic and infrasound phases of the event to better characterize the volcanic source. We highlight the need for the integration of the global infrasound International Monitoring System (IMS) network with local and regional infrasound arrays capable of providing a timely early warning to VAACs. This study opens new perspectives in volcano monitoring for hazard assessment and could represent, in the future, an efficient tool in supporting VAACs activity.</p>

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
A. Le Pichon ◽  
C. Pilger ◽  
L. Ceranna ◽  
E. Marchetti ◽  
G. Lacanna ◽  
...  

AbstractStromboli Volcano is well known for its persistent explosive activity. On July 3rd and August 28th 2019, two paroxysmal explosions occurred, generating an eruptive column that quickly rose up to 5 km above sea level. Both events were detected by advanced local monitoring networks operated by Istituto Nazionale di Geofisica e Vulcanologia (INGV) and Laboratorio di Geofisica Sperimentale of the University of Firenze (LGS-UNIFI). Signals were also recorded by the Italian national seismic network at a range of hundreds of kilometres and by infrasonic arrays up to distances of 3700 km. Using state-of-the-art propagation modeling, we identify the various seismic and infrasound phases that are used for precise timing of the eruptions. We highlight the advantage of dense regional seismo-acoustic networks to enhance volcanic signal detection in poorly monitored regions, to provide timely warning of eruptions and reliable source amplitude estimate to Volcanic Ash Advisory Centres (VAAC).


2020 ◽  
Author(s):  
Emanuele Marchetti ◽  
Maurizio Ripepe ◽  
Alexis Le Pichon ◽  
Constantino Listowski ◽  
Lars Ceranna ◽  
...  

<p>With the advent of civil aviation and growth in air traffic, the problem of volcanic ash encounter has become an issue of importance as a prompt response to volcanic eruptions is required to mitigate the impact of the volcanic hazard on aviation. Many volcanoes worldwide are poorly monitored, and most of the time notifications of volcanic eruptions are reported mainly based on satellite observations or visual observations. Among ground-based volcano monitoring techniques, infrasound is the only one capable of detecting explosive eruptions from distances of thousands of kilometers. On July 3 and August 28, 2019, two paroxysmal explosions occurred at Stromboli volcano. The events, that are similar in terms of energy and size to the peak explosive activity reported historically for the volcano, produced a significant emission of scoria, bombs and lapilli, that affected the whole island and fed an eruptive column that rose almost 5 km above the volcano. The collapse of the eruptive column also produced pyroclastic flows along the Sciara del Fuoco, a sector collapse on the northern flank of the volcano.</p><p>Being one of the best-monitored volcanoes of the world, the 2019 Stromboli paroxysmal explosions were observed in real-time and Civil Protection procedures started immediately. However, notification to the Toulouse Volcanic Ash Advisory Centre (VAAC) was not automated, and the VAA was issued only long after the event occurrence. The two explosions produced infrasound signals that were detected by several infrasound stations as far as Norway (IS37, 3380 km) and Azores islands (IS42, 3530 km). Despite of the latency due to the propagation time, infrasound-based notification arrays precedes the Volcanic Ash Advisories (VAAs) issued by Toulouse VACC. Following the same procedure applied for the Volcano Information System developed in the framework of the ARISE project, we show how infrasound array analysis could allow automatic, near-real-time identification of these eruptions with timely reliable source information. We highlight the need for an integration of the CTBT IMS infrasound network with local and regional infrasound arrays capable of providing a timely early warning to VAACs. This study opens new perspectives in volcano monitoring and could represent, in the future, an efficient tool in supporting VAACs activity.</p>


2020 ◽  
Author(s):  
Alexis Le Pichon ◽  
Christoph Pilger ◽  
Lars Ceranna ◽  
Emanuele Marchetti ◽  
Viviane Souty ◽  
...  

Abstract The Stromboli volcano is well known for its persistent explosive activity. On July 3rd and August 28th 2019, two paroxysmal explosions occurred, generating an eruptive column that quickly rose up to 5 km above sea level. For the first eruption, the Toulouse Volcanic Ash Advisory Center (VAAC) issued a volcanic ash advisory to the civil aviation users with a two-hour delay. The various processes of these events were monitored in the near and far fields by infrasonic arrays up to distance of 3700 km and by the Italian national seismic network at a range of hundreds of kilometres. Using state-of-the-art propagation modelling, we identify the various seismic and infrasound phases for precise timing of the eruptions. We highlight the advantage of a dense seismo-acoustic network to enhance the monitoring capability of a global network at a regional scale for providing both a reliable source characterisation and a timely early warning to VAACs.


Atmosphere ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 864
Author(s):  
Mathieu Gouhier ◽  
Mathieu Deslandes ◽  
Yannick Guéhenneux ◽  
Philippe Hereil ◽  
Philippe Cacault ◽  
...  

In 2010, the Eyjafjallajökull volcano erupted, generating an ash cloud causing unprecedented disruption of European airspace. Despite an exceptional situation, both the London and Toulouse Volcanic Ash Advisory Centres (VAAC) provided critical information on the location of the cloud and on the concentration of ash, thus contributing to the crisis management. Since then, substantial efforts have been carried out by the scientific community in order to improve remote sensing techniques and numerical modeling. Satellite instruments have proven to be particularly relevant for the characterization of ash cloud properties and a great help in the operational management of volcanic risk. In this study, we present the satellite-based system HOTVOLC developed at the Observatoire de Physique du Globe de Clermont-Ferrand (OPGC) using Meteosat geostationary satellite and designed for real-time monitoring of active volcanoes. After a brief presentation of the system we provide details on newly developed satellite products dedicated to the ash cloud characterization. This includes, in particular, ash cloud altitude and vertical column densities (VCD). Then, from the Stromboli 2018 paroxysm, we show how HOTVOLC can be used in a timely manner to assist the Toulouse VAAC in the operational management of the eruptive crisis. In the second part of the study, we provide parametric tests of the MOCAGE-Accident model run by the Toulouse VAAC from the April 17 Eyjafjallajökull eruption. For this purpose, we tested a range of eruption source parameters including the Total Grain Size Distribution (TGSD), the eruptive column profile, the top plume height and mass eruption rate (MER), as well as the fine ash partitioning. Finally, we make a comparison on this case study between HOTVOLC and MOCAGE-Accident VCD.


2015 ◽  
Vol 57 ◽  
Author(s):  
Kate Louise Wilkins ◽  
Shona Mackie ◽  
Matthew Watson ◽  
Helen N. Webster ◽  
David J. Thomson ◽  
...  

<div class="page" title="Page 1"><div class="layoutArea"><div class="column"><p><span>During the eruption of Eyjafjallajökull in April and May 2010, the London Volcanic Ash Advisory Centre demonstrated the importance of infrared (IR) satellite imagery for monitoring volcanic ash and validating the Met Office operational model, NAME. This model is used to forecast ash dispersion and forms much of the basis of the advice given to civil aviation. NAME requires a source term describing the properties of the eruption plume at the volcanic source. Elements of the source term are often highly uncertain and significant effort has therefore been invested into the use of satellite observations of ash clouds to constrain them. This paper presents a data insertion method, where satellite observations of downwind ash clouds are used to create effective ‘virtual sources’ far from the vent. Uncertainty in the model output is known to increase over the duration of a model run, as inaccuracies in the source term, meteorological data and the parameterizations of the modelled processes accumulate. This new technique, where the dis- persion model (DM) is ‘reinitialized’ part-way through a run, could go some way to addressing this. </span></p></div></div></div>


1997 ◽  
Author(s):  
Anatoliy N. Ivakin ◽  
Darrell R. Jackson

2017 ◽  
Vol 122 (8) ◽  
pp. 084103 ◽  
Author(s):  
E. Smirnova ◽  
A. Sotnikov ◽  
S. Ktitorov ◽  
H. Schmidt

2021 ◽  
pp. 004051752110238
Author(s):  
Oluwafemi P Akinmolayan ◽  
James M Manimala

Silica nanoparticle-impregnated Kevlar (SNK) fabric has better specific ballistic performance in comparison to its neat counterparts. For multifunctional structural applications using lightweight composites, combining this improved ballistic functionality with an acoustic functionality is desirable. In this study, acoustic characterization of neat and SNK samples is conducted using the normal-incidence impedance tube method. Both the absorption coefficient and transmission loss (TL) are measured in the 60–6000 Hz frequency range. The influence of parameters such as number of layers of neat or treated fabric, percentage by weight of nanoparticle addition, spacing between fabric layers, and residual porosity is examined. It is found that while absorption decreases with an increase in nanoparticle addition for frequencies above about 2500 Hz, increasing the number of layers shifts peak absorption to lower frequencies. By introducing an air-gap behind the fabric layer, dominant low-frequency (1000–3000 Hz) absorption peaks are obtained that correlate well with natural modes of mass-equivalent thin plates. Examining the influence of residual porosity by laminating the SNK samples reveals that it contributes to about 30–50% of the total absorption. Above about 1500 Hz, 3–5 dB of TL increase is obtained for SNK samples vis-à-vis the neat samples. TL is found to increase beyond that of the neat sample above a threshold frequency when an air-gap is introduced between two SNK layers. With an increase in the weight of nanoparticle addition, measured TL tends to be closer to mass law predictions. This study demonstrates that SNK fabric could provide improved acoustic performance in addition to its ballistic capabilities, making it suitable for multifunctional applications and could form the basis for the development of simplified models to predict the structural acoustic response of such nanoparticle–fabric composites.


2021 ◽  
Vol 11 (13) ◽  
pp. 5924
Author(s):  
Elisa Levi ◽  
Simona Sgarbi ◽  
Edoardo Alessio Piana

From a circular economy perspective, the acoustic characterization of steelwork by-products is a topic worth investigating, especially because little or no literature can be found on this subject. The possibility to reuse and add value to a large amount of this kind of waste material can lead to significant economic and environmental benefits. Once properly analyzed and optimized, these by-products can become a valuable alternative to conventional materials for noise control applications. The main acoustic properties of these materials can be investigated by means of a four-microphone impedance tube. Through an inverse technique, it is then possible to derive some non-acoustic properties of interest, useful to physically characterize the structure of the materials. The inverse method adopted in this paper is founded on the Johnson–Champoux–Allard model and uses a standard minimization procedure based on the difference between the sound absorption coefficients obtained experimentally and predicted by the Johnson–Champoux–Allard model. The results obtained are consistent with other literature data for similar materials. The knowledge of the physical parameters retrieved applying this technique (porosity, airflow resistivity, tortuosity, viscous and thermal characteristic length) is fundamental for the acoustic optimization of the porous materials in the case of future applications.


Author(s):  
Paolo La Torraca ◽  
Luca Larcher ◽  
Paolo Lugli ◽  
Marco Bobinger ◽  
Francisco J. Romero ◽  
...  

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