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Volcanica ◽  
2021 ◽  
Vol 4 (S1) ◽  
pp. 21-48
Author(s):  
Sebastian Garcia ◽  
Gabriela Badi

Argentina is a country that presents a complex situation regarding volcanic risk, where a total of 38 volcanoes are considered active. Although Argentina has no major cities close to these volcanoes, the continuous increase in economic activity and infrastructure near the Andean Codillera will increase exposure to volcano hazards in the future. Further, volcanic activity on the border between Argentina and Chile poses a unique challenge in relation to volcano monitoring and the management of volcanic emergencies. Additionally, due to atmospheric circulation patterns in the region (from West to East), Argentina is exposed to ashfall and ash dispersion from frequent explosive eruptions from Chilean volcanoes. Considering this, the Servicio Geológico Minero Argentino (SEGEMAR) decided to create and implement a Volcanic Threat Assessment Program, which includes the creation of the the first permanent volcano observatory for the country, the Observatorio Argentino de Vigilancia Volcánica (OAVV). Previously the Decepcion Island volcano observatory was created as a collaboration between the Instituto Antártico Argentino (IAA) and the Museo Nacional de Ciencias Naturales (MNCN) from the Consejo Superior de Investigaciones Científicas (CSIC). Argentina es un país que presenta una compleja situación con respecto al riesgo volcánico, donde un total de 38 volcanes son considerados activos. Aunque Argentina no tiene ciudades importantes cerca de estos volcanes, el continuo incremento de la actividad económica y la infraestructura cerca de la Cordillera de los Andes, generará en el futuro un aumento en la exposición a estos peligros. Además, la actividad volcánica en la frontera entre Argentina y Chile constituye un desafío único en relación con el monitoreo de volcanes y la gestión de emergencias volcánicas. Adicionalmente, debido a los patrones de circulación atmosférica en la región (desde el oeste hacia el este), Argentina está expuesta a la caída y dispersión de cenizas de las frecuentes erupciones explosivas de volcanes chilenos. Teniendo esto en cuenta, el Servicio Geológico Minero Argentino (SEGEMAR) decidió crear e implementar un programa de evaluación de amenazas volcánicas, que incluye, la creación del primer observatorio permanente de volcanes para el país, el Observatorio Argentino de Vigilancia Volcánica (OAVV). Previamente, el Observatorio Volcanológico de la Isla Decepción fue creado como una colaboración entre el Instituto Antártico Argentino (IAA) y el Museo Nacional de Ciencias Naturales (MNCN) del Consejo Superior de Investigaciones Científicas de España (CSIC).


Volcanica ◽  
2021 ◽  
Vol 4 (S1) ◽  
pp. 49-71
Author(s):  
Roger Machacca Puma ◽  
José Alberto Del Carpio Calienes ◽  
Marco Antonio Rivera Porras ◽  
Hernando Jhonny Tavera Huarache ◽  
Luisa Diomira Macedo Franco ◽  
...  

Volcano monitoring in Peru is carried out by the Instituto Geofísico del Perú (IGP), through its Centro Vulcanológico Nacional (CENVUL). CENVUL monitors 12 out of 16 volcanoes considered as historically active and potentially active in southern Peru and issues periodic bulletins about the volcanic activity and, depending on the alert-level of each volcano, also issues alerts and warnings of volcanic unrest, ash dispersion, and the occurrence of lahars. The information generated by CENVUL is disseminated to the civil authorities and the public through different information media (newsletters, e-mail, website, social media, mobile app, etc.). The IGP volcanology team was formed after the eruption of Sabancaya volcano in 1988. Since then, geophysical and geological studies, volcanic hazards assessments, and multidisciplinary monitoring realized by the IGP, have provided a comprehensive understanding of volcanic activity in Peru and forecast future eruptive scenarios. Currently, 80% of the historically active and potentially active volcanoes in Peru are equipped with networks of multiparameter instruments, with the seismic monitoring being the most widely implemented. In this report, we present the situation of volcanic monitoring in Peru, the monitoring networks, the techniques employed, as well as efforts to educate and inform the public and officials responsible for disaster risk management.


2021 ◽  
Vol 21 (10) ◽  
pp. 2973-2992
Author(s):  
Matthieu Plu ◽  
Barbara Scherllin-Pirscher ◽  
Delia Arnold Arias ◽  
Rocio Baro ◽  
Guillaume Bigeard ◽  
...  

Abstract. High-quality volcanic ash forecasts are crucial to minimize the economic impact of volcanic hazards on air traffic. Decision-making is usually based on numerical dispersion modelling with only one model realization. Given the inherent uncertainty of such an approach, a multi-model multi-source term ensemble has been designed and evaluated for the Eyjafjallajökull eruption in May 2010. Its use for flight planning is discussed. Two multi-model ensembles were built: the first is based on the output of four dispersion models and their own implementation of ash ejection. All a priori model source terms were constrained by observational evidence of the volcanic ash cloud top as a function of time. The second ensemble is based on the same four dispersion models, which were run with three additional source terms: (i) a source term obtained from a model background constrained with satellite data (a posteriori source term), (ii) its lower-bound estimate and (iii) its upper-bound estimate. The a priori ensemble gives valuable information about the probability of ash dispersion during the early phase of the eruption, when observational evidence is limited. However, its evaluation with observational data reveals lower quality compared to the second ensemble. While the second ensemble ash column load and ash horizontal location compare well to satellite observations, 3D ash concentrations are negatively biased. This might be caused by the vertical distribution of ash, which is too much diluted in all model runs, probably due to defaults in the a posteriori source term and vertical transport and/or diffusion processes in all models. Relevant products for the air traffic management are horizontal maps of ash concentration quantiles (median, 75 %, 99 %) at a finely resolved flight level grid as well as cross sections. These maps enable cost-optimized consideration of volcanic hazards and could result in much fewer flight cancellations, reroutings and traffic flow congestions. In addition, they could be used for route optimization in the areas where ash does not pose a direct and urgent threat to aviation, including the aspect of aeroplane maintenance.


Author(s):  
Bhabatosh Biswas ◽  
Biplab Hazra ◽  
Subhabrata Chakraborty ◽  
Nillohit Mukherjee ◽  
Arijit Sinha

Alkali-treated discontinuous cellulosic fibers (jute and sisal)-based heat-treated silanized fly ash-dispersed hybrid polyester composites were fabricated using a compression molding technique. The morphological features were observed using a scanning electron microscope and a high-resolution transmission electron microscope. The bulk mechanical testing namely, microhardness, tensile, flexural as well as Izod impact was successfully executed. The significant effect of the filler (cellulosic fibers as well as modified fly ash) dispersion within the polymeric matrix with respect to mechanical properties was thoroughly examined in this present investigation.


2021 ◽  
Vol 3 (2) ◽  
pp. 46-56
Author(s):  
Rista Hernandi Virgianto ◽  
Alia Rahmi Nasution

The eruption of Sinabung on June 9, 2019, was categorized as a red code in the warning report for flights. Volcanic ash from volcanic eruptions is a serious threat in the world of aviation with the most dangerous ash particles are 6-10 μm and 37 μm in diameter. To enrich our understanding and modeling performances of the volcanic ash dispersion for the Sinabung eruption case, it is necessary to simulate the dispersion of volcanic ash in those particular sizes to see its distribution which can impact flight routes. The method used was the analysis of the direction and dispersion of the particular volcanic ash using Weather Research Forecast-Chemistry (WRF-Chem) and compared it with the volcanic ash warning information on flight routes issued by Volcanic Ash Advisory Centers (VAAC)-Darwin. In general, WRF-Chem can simulate the distribution of volcanic ash from the eruption of Sinabung at the two-particle sizes at different heights, and found the difference in the distribution direction of the two groups of the particle sizes. Comparison results with warning information from VAAC-Darwin and previous study, WRF-Chem simulation shows a good concordance in the dispersion direction.


2021 ◽  
Vol 1869 (1) ◽  
pp. 012200
Author(s):  
M Delina ◽  
T S Oktafiandariento ◽  
R Fahdiran

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jooyong Lee ◽  
Sungsu Lee ◽  
HyunA Son ◽  
Waon-ho Yi

AbstractMt. Baekdu’s eruption precursors are continuously observed and have become a global social issue. Volcanic activities in neighboring Japan are also active. There are no direct risks of proximity-related disasters in South Korea from the volcanic eruptions at Japan or Mt. Baekdu; however, severe impacts are expected from the spread of volcanic ash. Numerical analysis models are generally used to predict and analyze the diffusion of volcanic ash, and each numerical analysis model has its own limitations caused by the computational algorithm it employs. In this study, we analyzed the PUFF–UAF model, an ash dispersion model based on the Lagrangian approach, and observed that the number of particles used in tracking substantially affected the results. Even with the presence of millions of particles, the concentration of ash predicted by the PUFF–UAF model does not accurately represent the dispersion. To overcome this deficit and utilize the computational efficiency of the Lagrangian model, we developed a PUFF–Gaussian model to consider the dispersive nature of ash by applying the Gaussian dispersion theory to the results of the PUFF–UAF model. The results of the proposed method were compared with the field measurements from actual volcanic eruptions, and the comparison showed that the proposed method can produce reasonably accurate predictions for ash dispersion.


2021 ◽  
pp. 95-104
Author(s):  
A. N. LUKYANOV ◽  
◽  
A. V. GANSHIN ◽  
V. A. YUSHKOV ◽  
A. S. VYAZANKIN ◽  
...  

A short description and some applications of the trajectory and dispersion models developed in Central Aerological Observatory (CAO) for studying the stratospheric and tropospheric transport of pollutants are presented. The TRACAO trajectory model is applied to investigate the processes related to the ozone depletion in the winter polar stratosphere, in order to study the mid-latitude stratosphere-troposphere exchange, as well as to analyze balloon and aircraft (M55 “Geophysics,” Yak-42D “Roshydromer”) observations. Then based on the TRACAO, the GLADIM dispersion model that simulates trajectories of the set of particles with the eddy diffusion parameterization and determines the pollutant concentration at the regular grid points, was developed. The dispersion model was applied to simulate volcanic ash dispersion and carbon dioxide profile reconstruction. The model validation was done by comparisons with the results of the widely used FLEXPART model. Nowadays these models are used at the “Middle Atmosphere” Regional Information and Analytic Center established in CAO.


2020 ◽  
Vol 103 (3) ◽  
pp. 3377-3399
Author(s):  
Yosuke Tomii ◽  
Tomoya Shibayama ◽  
Yuta Nishida ◽  
Ryota Nakamura ◽  
Non Okumura ◽  
...  
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