Large-scale particulate air pollution and chemical fingerprint of volcanic sulfate aerosols from the 2014-2015 Holuhraun flood lava eruption of Bárðarbunga volcano (Iceland)

• Published in: Atmospheric Chemistry and Physics
• Main Authors: Boichu, Marie, Favez, Olivier, Riffault, Véronique, Petit, Jean-Eudes, Zhang, Yunjiang, Brogniez, Colette, Sciare, Jean, Chiapello, Isabelle, Clarisse, Lieven, Zhang, Shouwen, Pujol-Söhne, Nathalie, Tison, Emmanuel, Delbarre, Hervé, Goloub, Philippe
• Other Authors: Laboratoire d’Optique Atmosphérique - UMR 8518 (LOA), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Institut National de l'Environnement Industriel et des Risques (INERIS), Centre for Energy and Environment (CERI EE - IMT Nord Europe), Ecole nationale supérieure Mines-Télécom Lille Douai (IMT Nord Europe), Institut Mines-Télécom Paris (IMT)-Institut Mines-Télécom Paris (IMT), Ecole nationale supérieure Mines-Télécom Lille Douai (IMT Lille Douai), Institut Mines-Télécom Paris (IMT), Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), The Cyprus Institute, Energy, Environment and Water Research Center, Spectroscopie de l'atmosphère, Service de Chimie Quantique et Photophysique, Université libre de Bruxelles (ULB), Service de Chimie Quantique et Photophysique, ATMO Hauts de France Lille, Laboratoire de Physico-Chimie de l'Atmosphère (LPCA), Université du Littoral Côte d'Opale (ULCO), ANR VOLCPLUME (ANR-15-CE04-0003-01), Labex CaPPA (ANR-LABX-0005-01), CPER CLIMIBIO, Chantier Arctique, projet PARCS (Pollution in the Arctic system), ANR-15-CE04-0003,VOLCPLUME,Les panaches volcaniques: emissions, chimie/transport et impact sur l'atmosphère et le climat(2015)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2019
• Subjects: air pollution; volcanic sulfate aerosols; Aerosol chemical speciation monitor; industrial emissions; sulfur dioxide; EMEP; [SDE]Environmental Sciences; [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [SDU.STU.VO]Sciences of the Universe [physics]/Earth Sciences/Volcanology; [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]; [CHIM.INOR]Chemical Sciences/Inorganic chemistry; Holuhraun; Aerosol Robotic Network; Iceland; Islande
• Online Access: https://hal.science/hal-02383172; https://hal.science/hal-02383172/document; https://hal.science/hal-02383172/file/acp-19-14253-2019.pdf; https://doi.org/10.5194/acp-19-14253-2019

International audience Volcanic sulfate aerosols play a key role in air quality and climate. However, the rate of oxidation of sulfur dioxide (SO2) precursor gas to sulfate aerosols (SO4^2-) in volcanic plumes is poorly known, especially in the troposphere. Here we determine the chemical speciation as well as the intensity and temporal persistence of the impact on air quality of sulfate aerosols from the 2014-2015 Holuhraun flood lava eruption of Icelandic volcano Bárðarbunga. To do so, we jointly analyse a set of SO2 observations from satellite (OMPS and IASI) and ground-level measurements from air quality monitoring stations together with high temporal resolution mass spectrometry measurements of an Aerosol Chemical Speciation Monitor (ACSM) performed far from the volcanic source. We explore month/year long ACSM data in France from stations in contrasting environments, close and far from industrial sulfur-rich activities. We demonstrate that volcanic sulfate aerosols exhibit a distinct chemical signature in urban/rural conditions, with NO3:SO4 mass concentration ratios lower than for non-volcanic background aerosols. These results are supported by thermodynamic simulations of aerosol composition, using the ISORROPIA II model, which show that ammonium sulfate aerosols are preferentially formed at a high concentration of sulfate, leading to a decrease in the production of particulate ammonium nitrate. Such a chemical signature is however more difficult to identify at heavily polluted industrial sites due to a high level of background noise in sulfur. Nevertheless, aged volcanic sulfates can be distinguished from freshly emitted industrial sulfates according to their contrasting degree of anion neutralization. Combining AERONET (AErosol RObotic NETwork) sunphotometric data with ACSM observations, we also show a long persistence over weeks of pollution in volcanic sulfate aerosols, while SO2 pollution disappears in a few days at most. Finally, gathering 6-month long datasets from 27 sulfur monitoring stations of ...