H2020Индивидуална стипендия2016–2018

VOLTAIC · VOLcanic lighTning: a lAb and fIeld ApproaCh

„Хоризонт 2020“ — Действия „Мария Склодовска-Кюри“

Период: 2016-09-01 → 2018-08-31
Финансиране от ЕС: 171 461 €
Участници: 1
Схема: MSCA-IF-EF-ST

Линиите свързват координатора с партньорите.

Накратко на български

Вулканичните светкавици се анализират, за да се определи количеството пепел и скоростта на изригване, както при вулкана Сакураджима. Това помага за по-доброто проследяване на пепелните облаци, които застрашават авиацията, инфраструктурата и здравето на хората.

Този кратък обзор е генериран от изкуствен интелект

Кратко обяснение, генерирано от езиков модел по текста на CORDIS. Оригиналът е по-долу.

Резултати накратко

VOLcanic lighTning: a lAb and fIeld ApproaCh

Ash plumes are a major hazard in explosive volcanism, because they impact air traffic, infrastructures and health of the population. Detecting and quantifying remotely ash plumes is challenging, in particular in bad weather and/or at remote volcanoes. This context raised the awareness of the community to develop innovative detection techniques. One of the most promising uses monitoring of lightning produced by the plume. Several explosive eruptions (Augustine 2006, Redoubt 2009, Eyjafjallajökull 2010, Bogoslof 2017) prove the ubiquitousness of electrical activity in volcanic plumes. In addition, volcanic lightning is easily detectable remotely by antenna networks recording electrical potential changes around volcanoes, or the radio-frequencies they produce. A key issue is to determine the sensitivity of such systems. Additionally, being able to derive the volume of ash, exit velocity and grain size produced by an explosion is of major interest for the modelling of atmospheric ash dispersion. These objectives were the core of VOLTAIC.The experimental results showed that the key parameter to monitor is the total amount of charge carried by the flashes (i.e. the cumulative magnitude of the discharges). The cumulative magnitude of the discharges is proportional to the volume of erupted ash and the pressure release during the explosion. Another key parameter is the ash grain size which controls how particles can segregate and generate clusters of opposite polarity. Field studies demonstrate that these conclusions remain valid at the scale of a real volcano, and allow an estimation of the lightning generation threshold in the specific case of Sakurajima volcano.

Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз

Цел на проекта

Since the 2010 Eyjafjallajökull eruption in Iceland, which evidenced the fragility and vulnerability of our globalized society to disastrous socio-economic impacts of volcanoes, ash monitoring has become a priority of the European Commission. In this scope, lightning, observed in numerous eruptions, and easily detectable in all weather conditions, is proving strong potential as a novel monitoring tool of ash plumes. Although thunderstorm lightning have been studied for decades, little is known on the mechanisms of ash particles charging and how discharges occur in explosive eruptions, thus preventing to link lightning occurrence with ash plume characteristics.The aim of this project is hence to combine laboratory and field studies to advance our knowledge of electrical properties of ash plumes. I will take advantage of a unique experimental setup developed at LMU-Munich to bridge the gap between physical theory and field observations. Generating volcanic lightning in the lab under constrained conditions, and comparing them with field observations, I will derive quantitative relationships between the plume characteristics (temperature, velocity, and ash concentration), the charging and the segregation of ash particles, and the occurrence of electrical discharges. Two field campaigns are planned for this scope at the permanently active Sakurajima volcano (Japan), where volcanic lightning is frequently observed. High-speed visible-light cameras will be used to measure lightning while a thermal camera will unravel the plume structure and dynamics. In the scope of a secondment at Hamburg University, I will use a numerical model to simulate the plume microphysics and will implement image-processing methods to build the first complete database coupling plume and lightning characteristics.Through this project we aim at the first quantitative interpretation of volcanic lightning with the scope of keeping Europe at the forefront of volcano research and hazard mitigation.

Оригинален текст от CORDIS (на английски).

Участници

LUDWIG-MAXIMILIANS-UNIVERSITAET MUENCHEN · PlaneggКоординаторГермания