Andrew G. Allen

University of Melbourne

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Roy M. Harrison

University of Birmingham

Arnaldo Alves Cardoso

Universidade Estadual Paulista (Unesp)

B. Davison

Edinburgh Napier University

Tamsin A. Mather

University of Oxford

Clive Oppenheimer

University of Cambridge

A. J. S. McGonigle

University of Sheffield

David M. Pyle

University of Oxford

C. N. Hewitt

Lancaster University

Jonathan James

Clinical Physiology Associates

Lennart Robertson

Swedish Meteorological and Hydrological Institute

Cooperative Institutions

National Centre for Atmospheric Science

University of Leeds

University of Birmingham

University of Manchester

University of East Anglia

University of York

University of Cambridge

Universidade de São Paulo

Max Planck Institute for Chemistry

University of Helsinki

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Journal of Atmospheric Chemistry (2002)

Andrew G. Allen B. Davison Jonathan James Lennart Robertson Roy M. Harrison

Trace gas

10.1023/a:1013868729960

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Citations (15)

Sources, size distribution, and downwind grounding of aerosols from

Andrew G. Allen Tamsin A. Mather A. J. S. McGonigle Alessandro Aiuppa Pierre Delmelle

Source

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Influence of sugar cane burning on aerosol soluble ion composition in Southeastern Brazil

Atmospheric Environment (2004)

Andrew G. Allen Arnaldo Alves Cardoso Gisele O. da Rocha

Inorganic ions

10.1016/j.atmosenv.2004.06.019

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Citations (120)

Size distributions of fine silicate and other particles in Masaya's volcanic plume

Journal of Geophysical Research Atmospheres (2009)

Robert Martin Tamsin A. Mather David M. Pyle Matthew Power V. I. Tsanev

Direct‐sampling and remote‐sensing measurements were made at the crater rim of Masaya volcano (Nicaragua) to sample the aerosol plume emanating from the active vent. We report the first measurements of the size distribution of fine silicate particles ( d < 10 μ m) in Masaya's plume, by automated scanning electron microscopy (QEMSCAN) analysis of a particle filter. The particle size distribution was approximately lognormal with modal d ∼ 1.15 μ m. The majority of these particles were found to be spherical. These particles are interpreted to be droplets of quenched magma produced by a spattering process. Compositional analyses confirm earlier reports that the fine silicate particles show a range of compositions between that of the degassing magma and nearly pure silica and that the extent of compositional variability decreases with increasing particle size. These results indicate that fine silicate particles are altered owing to reactions with acidic droplets in the plume. The emission flux of fine silicate particles was estimated as ∼10 11 s −1 , equivalent to ∼55 kg d −1 . Sun photometry, aerosol spectrometry, and thermal precipitation were used to determine the overall particle size distribution of the plume (0.01 < d ( μ m) < 10). Sun photometry and aerosol spectrometry measurements indicate the presence of a large number of particles (assumed to be aqueous) with d ∼ 1 μ m. Aerosol spectrometry measurements further show an increase in particle size as the nighttime approached. The emission flux of particles from Masaya was estimated as ∼10 17 s −1 , equivalent to ∼5.5 Mg d −1 where d < 4 μ m.

Panache

10.1029/2008jd011211

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Citations (76)

An analysis of diurnal cycles in the mass of ambient aerosols derived from biomass burning and agro‐industry

Journal of Geophysical Research Atmospheres (2013)

Letícia Caetano-Silva Andrew G. Allen Michele Lima-Souza Arnaldo Alves Cardoso Maria Lucia Arruda Moura Campos

Abstract Strong diurnal cycles in ambient aerosol mass were observed in a rural region of Southeast Brazil where the trace composition of the lower troposphere is governed mainly by emissions from agro‐industry. An optical particle counter was used to record size‐segregated aerosol number concentrations between 13 May 2010 and 15 March 2011. The data were collected every 10 min and used to calculate aerosol mass concentrations. Aerosol samples were also collected onto filters during daytime (10:00–16:00 local time) and nighttime (20:00–06:00) periods, for subsequent analysis of soluble ions and water‐soluble organic carbon. Biomass burning aerosols predominated during the dry winter, while secondary aerosols were most important in the summer rainy season. In both seasons, diurnal cycles in calculated aerosol mass concentrations were due to the uptake of water by the aerosols and, to a lesser extent, to emissions and secondary aerosol formation. In neither season could the observed mass changes be explained by changes in the depth of the boundary layer. In the summer, nighttime increases in aerosol mass ranged from 2.7‐fold to 81‐fold, depending on particle size, while in the winter, the range was narrower, from 2.2‐fold to 9.5‐fold, supporting the possibility that the presence of particles derived from biomass burning reduced the overall ability of the aerosols to absorb water.

Mass concentration (chemistry)

Trace gas

Diurnal temperature variation

Dry season

10.1002/jgrd.50630

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Citations (13)

Characterization and evolution of tropospheric plumes from Lascar and Villarrica volcanoes, Chile

Journal of Geophysical Research Atmospheres (2004)

Tamsin A. Mather V. I. Tsanev David M. Pyle A. J. S. McGonigle Clive Oppenheimer

Direct sampling (filter pack and impactor) and remote sensing (ultraviolet spectroscopy and Sun photometry) of the plumes of Lascar and Villarrica volcanoes, Chile, reveal that both are significant and sustained emitters of SO 2 (28 and 3.7 kg s −1 , respectively), HCl (9.6 and 1.3 kg s −1 , respectively), HF (4.5 and 0.3 kg s −1 , respectively) and near‐source sulfate aerosol (0.5 and 0.1 kg s −1 , respectively). Aerosol plumes are characterized by particle number fluxes (0.08–4.0 μm radius) of ∼10 17 s −1 (Lascar) and ∼10 16 s −1 (Villarrica), the majority of which will act as cloud condensation nuclei at supersaturations >0.1%. Impactor studies suggest that the majority of these particles contain soluble SO 4 2− . Most aerosol size distributions were bimodal with maxima at radii of 0.1–0.2 μm and 0.7–1.5 μm. The mean particle effective radius ( R eff ) ranged from 0.1 to 1.5 μm, and particle size evolution during transport appears to be controlled by particle water uptake (Villarrica) or loss (Lascar) rather than sulfate production.

Cloud condensation nuclei

Particle (ecology)

10.1029/2004jd004934

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Citations (116)

Primary sulfate aerosol and associated emissions from Masaya Volcano, Nicaragua

Journal of Geophysical Research Atmospheres (2002)

Andrew G. Allen Clive Oppenheimer Martin Ferm P J Baxter L. A. Horrocks

Existing studies of the composition of volcanic plumes generally interpret the presence of sulfate aerosol as the result of comparatively slow oxidation of gaseous SO 2 . We report here new observations from Masaya Volcano, Nicaragua, which demonstrate that sulfate aerosol may also be emitted directly from volcanic vents. Simultaneous aerosol and gaseous S, Cl, and F compounds were collected at the rim of the passively degassing crater in May 2001. Mean concentrations of SO 4 2− , Cl − , and F − within the plume were 83, 1.2, and 0.37 μg m −3 , respectively (fine aerosol fraction <2.5 μm) and 16, 2.5, and 0.56 μg m −3 , respectively (coarse aerosol fraction >2.5 μm). The aerosols were highly acidic, with estimated pH of <1.0 in the fine aerosols. Sulfate was present mainly in smaller particles, with the fine fraction accounting for ≈80% of the mass. The bulk of the sulfate was emitted directly from the magmatic vent. Acidity in the aerosols derived from the presence of sulfuric acid and, to a lesser extent, hydrofluoric acid, with [H + ]/[SO 4 2− ] equivalent values of 0.5–0.8 and 0.3–3 for fine and coarse aerosols, respectively. Gas phase/aerosol phase mass ratios were, on average, 458 (S), 330 (F), and 186 (Cl), with ranges of 95–1178, 37–659, and 43–259, respectively. These observations of highly acidic aerosol emitted directly from crater vents have implications for plume chemistry and environmental and health impacts of volcanic degassing.

Sulfate aerosol

Mass concentration (chemistry)

Panache

Fraction (chemistry)

10.1029/2002jd002120

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Citations (118)

Volcanic source for fixed nitrogen in the early Earth's atmosphere

Geology (2004)

Tamsin A. Mather David M. Pyle Andrew G. Allen

Research Article| October 01, 2004 Volcanic source for fixed nitrogen in the early Earth's atmosphere Tamsin A. Mather; Tamsin A. Mather 1Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK Search for other works by this author on: GSW Google Scholar David M. Pyle; David M. Pyle 1Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK Search for other works by this author on: GSW Google Scholar Andrew G. Allen Andrew G. Allen 2University of Birmingham, School of Geography, Earth and Environmental Sciences, Edgbaston, Birmingham B15 2TT, UK Search for other works by this author on: GSW Google Scholar Author and Article Information Tamsin A. Mather 1Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK David M. Pyle 1Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK Andrew G. Allen 2University of Birmingham, School of Geography, Earth and Environmental Sciences, Edgbaston, Birmingham B15 2TT, UK Publisher: Geological Society of America Received: 07 Jun 2004 Revision Received: 14 Jun 2004 Accepted: 16 Jun 2004 First Online: 02 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (2004) 32 (10): 905–908. https://doi.org/10.1130/G20679.1 Article history Received: 07 Jun 2004 Revision Received: 14 Jun 2004 Accepted: 16 Jun 2004 First Online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Tamsin A. Mather, David M. Pyle, Andrew G. Allen; Volcanic source for fixed nitrogen in the early Earth's atmosphere. Geology 2004;; 32 (10): 905–908. doi: https://doi.org/10.1130/G20679.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Hot volcanic vents promote the thermal fixation of atmospheric N2 into biologically available forms. The importance of this process for the global nitrogen cycle is poorly understood. At Masaya volcano, Nicaragua, NO and NO2 are intimately associated with volcanic aerosol, such that NOx levels reach as much as an order of magnitude above local background. In-plume HNO3 concentrations are elevated above background to an even greater extent (≤50 μmol·m−3). We estimate the production efficiency of fixed nitrogen at hot vents to be ∼3 × 10−8 mol·J−1, implying present-day global production of ∼109 mol of fixed N per year. Although conversion efficiency would have been lower in a preoxygenated atmosphere, we suggest that subaerial volcanoes potentially constituted an important source of fixed nitrogen in the early Earth, producing as much as ∼1011 mol·yr−1 of fixed N during major episodes of volcanism. These fluxes are comparable to estimated nitrogen-fixation rates in the prebiotic Earth from other major sources such as bolide impacts and thunderstorm and volcanic lightning. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

10.1130/g20679.1

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Citations (97)

Measurements of the atmospheric particle size distribution of trace metals in central England

Journal of Aerosol Science (2000)

Andrew G. Allen Roy M. Harrison Kym E. Jarvis Joanna C. Greenwood John G. Williams

TRACE (psycholinguistics)

Particle (ecology)

10.1016/s0021-8502(00)90381-1

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Citations (0)

Understanding aerosol formation mechanisms in a subtropical atmosphere impacted by biomass burning and agroindustry