Balloon-borne measurement of the aerosol size distribution from an Icelandic flood basalt eruption

• Published in: Earth and Planetary Science Letters
• Main Authors: Vignelles, Damien, Roberts, T., Carboni, E., Ilyinskaya, E., Pfeffer, M., Dagsson Waldhauserova, P., Schmidt, A., Berthet, Gwenaël, Jegou, Fabrice, Renard, Jean-Baptiste, Ólafsson, H., Bergsson, B., Yeo, R., Fannar Reynisson, N., Grainger, R.G., Galle, B., Conde, V., Arellano, S., Lurton, T., Coute, B., Duverger, Vincent
• 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, School of Earth and Environment Leeds (SEE), University of Leeds, Icelandic Meteorological Office, Departments of Physical and Earth Sciences, University of Iceland Reykjavik, Department of Earth and Space Sciences Göteborg, Chalmers University of Technology Göteborg, ANR-10-LABX-0100,VOLTAIRE,Geofluids and Volatil elements – Earth, Atmosphere, Interfaces – Resources and Environment(2010)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2016
• Subjects: volcano plume; balloon; Iceland; aerosol counter; in-situ measurement; [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]; [SDU.STU.VO]Sciences of the Universe [physics]/Earth Sciences/Volcanology; Holuhraun
• Online Access: https://hal-insu.archives-ouvertes.fr/insu-01382430; https://hal-insu.archives-ouvertes.fr/insu-01382430/document; https://hal-insu.archives-ouvertes.fr/insu-01382430/file/local_243683.pdf; https://doi.org/10.1016/j.epsl.2016.08.027

International audience We present in situ balloon-borne measurements of aerosols in a volcanic plume made during the Holuhraun eruption (Iceland) in January 2015. The balloon flight intercepted a young plume at 8 km distance downwind from the crater, where the plume is ∼15 min of age. The balloon carried a novel miniature optical particle counter LOAC (Light Optical Aerosol Counter) which measures particle number concentration and size distribution in the plume, alongside a meteorological payload. We discuss the possibility of calculating particle flux by combining LOAC data with measurements of sulfur dioxide flux by ground-based UV spectrometer (DOAS).The balloon passed through the plume at altitude range of 2.0–3.1 km above sea level (a.s.l.). The plume top height was determined as 2.7–3.1 km a.s.l., which is in good agreement with data from Infrared Atmospheric Sounding Interferometer (IASI) satellite. Two distinct plume layers were detected, a non-condensed lower layer (300 m thickness) and a condensed upper layer (800 m thickness). The lower layer was characterized by a lognormal size distribution of fine particles (0.2 μm diameter) and a secondary, coarser mode (2.3 μm diameter), with a total particle number concentration of around 100 cm−3 in the 0.2–100 μm detection range. The upper layer was dominated by particle centered on 20 μm in diameter as well as containing a finer mode (2 μm diameter). The total particle number concentration in the upper plume layer was an order of magnitude higher than in the lower layer.We demonstrate that intercepting a volcanic plume with a meteorological balloon carrying LOAC is an efficient method to characterize volcanic aerosol properties. During future volcanic eruptions, balloon-borne measurements could be carried out easily and rapidly over a large spatial area in order to better characterize the evolution of the particle size distribution and particle number concentrations in a volcanic plume.