African volcanic emissions influencing atmospheric aerosols over the Amazon rain forest

• Verfasst von: Saturno Iribarren, Jorge Luis [VerfasserIn]
• Verfasst von: Ditas, Florian [VerfasserIn]
• Verfasst von: Bobrowski, Nicole [VerfasserIn]
• Titel: African volcanic emissions influencing atmospheric aerosols over the Amazon rain forest
• Verf.angabe: Jorge Saturno, Florian Ditas, Marloes Penning de Vries, Bruna A. Holanda, Mira L. Pöhlker, Samara Carbone, David Walter, Nicole Bobrowski, Joel Brito, Xuguang Chi, Alexandra Gutmann, Isabella Hrabe de Angelis, Luiz A.T. Machado, Daniel Moran-Zuloaga, Julian Rüdiger, Johannes Schneider, Christiane Schulz, Qiaoqiao Wang, Manfred Wendisch, Paulo Artaxo, Thomas Wagner, Ulrich Pöschl, Meinrat O. Andreae, and Christopher Pöhlker
• E-Jahr: 2018
• Jahr: 23 July 2018
• Umfang: 15 S.
• Fussnoten: Gesehen am 22.05.2019
• Titel Quelle: Enthalten in: Atmospheric chemistry and physics
• Ort Quelle: Katlenburg-Lindau : EGU, 2001
• Jahr Quelle: 2018
• Band/Heft Quelle: 18(2018), 14, Seite 10391-10405
• ISSN Quelle: 1680-7324
• DOI: doi:10.5194/acp-18-10391-2018
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1666109169

Abstract

Abstract. The long-range transport (LRT) of trace gases and aerosol particles plays an important role for the composition of the Amazonian rain forest atmosphere. Sulfate aerosols originate to a substantial extent from LRT sources and play an important role in the Amazonian atmosphere as strongly light-scattering particles and effective cloud condensation nuclei. The transatlantic transport of volcanic sulfur emissions from Africa has been considered as a source of particulate sulfate in the Amazon; however, direct observations have been lacking so far. This study provides observational evidence for the influence of emissions from the Nyamuragira-Nyiragongo volcanoes in Africa on Amazonian aerosol properties and atmospheric composition during September 2014. Comprehensive ground-based and airborne aerosol measurements together with satellite observations are used to investigate the volcanic event. Under the volcanic influence, hourly mean sulfate mass concentrations in the submicron size range reached up to 3.6 <span class="inline-formula">µ</span>g m<span class="inline-formula">⁻³</span> at the Amazon Tall Tower Observatory, the highest value ever reported in the Amazon region. The substantial sulfate injection increased the aerosol hygroscopicity with <span class="inline-formula"><i>κ</i></span> values up to 0.36, thus altering aerosol-cloud interactions over the rain forest. Airborne measurements and satellite data indicate that the transatlantic transport of volcanogenic aerosols occurred in two major volcanic plumes with a sulfate-enhanced layer between 4 and 5 km of altitude. This study demonstrates how African aerosol sources, such as volcanic sulfur emissions, can substantially affect the aerosol cycling and atmospheric processes in Amazonia.</p>