In situ measurement of the Icelandic Holuhraun/ Bárðarbunga volcanicplume in an early “young state” using a LOAC

• Main Authors: Vignelles, Damien, Roberts, Tjarda J., Carboni, Elisa, Dagsson-Waldhauserova, Pavla, Berthet, Gwenaël, Jegou, Fabrice, Renard, Jean-Baptiste, Olafsson, Haraldur, Bergsson, Baldur, Yeo, Richard, Reynisson, Njall Fannar, Grainger, Roy, Pfeffer, Melissa A., Lurton, Thibaut, Duverger, Vincent, Coute, Benoit
• Other Authors: Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales Paris (CNES), Department of Atmospheric, Oceanic and Planetary Physics Oxford (AOPP), University of Oxford Oxford, University of Iceland Reykjavik, Icelandic Meteorological Office (IMO), Sub-Department of Atmospheric Oceanic and Planetary Physics Oxford
• Format: Conference Object
• Language: English
• Published: HAL CCSD 2016
• Subjects: [SDU]Sciences of the Universe [physics]; Holuhraun; Laki; Renard; Iceland
• Online Access: https://hal-insu.archives-ouvertes.fr/insu-02545369

International audience Volcanic eruptions have huge societal and economic consequences. In Iceland, one of the best known examples isthe Laki eruption (1783-84 CE) (Thordarson and Self, 2003) which caused the death of > 20% of the Icelandicpopulations and likely increased European levels of mortality through air pollution (Witham and Oppenheimer,2004). The recent fissure eruption at Holuhraun (31 August 2014 – 27 February 2015) was a major source ofsulfur gases and aerosols and caused also both local and European-wide deteriorations to air quality (Gislason etal. 2015; Schmidt et al. 2015).The capability of atmospheric models to predict volcanic plume impacts is limited by uncertainties in thenear-source plume state. Most in-situ measurements of the elevated plume involve interception of aged plumesthat have already chemically or physically evolved. Small portable sensors airborne drone or balloon platformsoffer a new possibility to characterize volcano plumes near to source.We present the results of a balloon flight through the plume emitted by Baugur the main vent during the nightof the January 22th 2015. The balloon carrying a LOAC (Renard et al. 2015) has intercepted the plume at 8kmdistance downwind from the crater which represents a plume age of approximately 15 minutes. The plume waslocated in altitude between 2 and 3.1km above the sea level. Two layers were observed, a non-condensed lowerlayer and a condensed upper layer. The lower layer of 400m thick was characterized by a mode of fine particlescentered on 0.2m in diameter and a second mode centered on 2.3m in diameter and a total particle concentrationaround 100 particles per cubic centimeter. The upper layer of 800m thick was a cloud-like signature with dropletscentered on 20 m in diameter and a fine mode, the total particles concentrations was 10 times higher than thefirst layer. The plume top height was determined between 2.7 and 3.1 km, the plume height is in good agreementwith an estimate made by analysis of IASI satellite remote sensing ...