Contributions of biomass-burning, urban, and biogenic emissions to the concentrations and light-absorbing properties of particulate matter in central Amazonia during the dry season

Simple item page
dc.contributor.authorde Sá, Suzane S.
dc.contributor.authorRizzo, Luciana V.
dc.contributor.authorPalm, Brett B.
dc.contributor.authorCampuzano-Jost, Pedro
dc.contributor.authorDay, Douglas A.
dc.contributor.authorYee, Lindsay D.
dc.contributor.authorWernis, Rebecca
dc.contributor.authorIsaacman-VanWertz, Gabriel
dc.contributor.authorBrito, Joel
dc.contributor.authorCarbone, Samara
dc.contributor.authorLiu, Yingjun J.
dc.contributor.authorSedlacek, Arthur
dc.contributor.authorSpringston, Stephen
dc.contributor.authorGoldstein, Allen H.
dc.contributor.authorBarbosa, H. M. J.
dc.contributor.authorAlexander, M. Lizabeth
dc.contributor.authorArtaxo, Paulo
dc.contributor.authorJimenez, Jose L.
dc.contributor.authorMartin, Scot T.
dc.date.accessioned2024-06-28T18:10:18Z
dc.date.available2024-06-28T18:10:18Z
dc.date.issued2019-06-18
dc.description.abstractUrbanization and deforestation have important impacts on atmospheric particulate matter (PM) over Amazonia. This study presents observations and analysis of PM₁ concentration, composition, and optical properties in central Amazonia during the dry season, focusing on the anthropogenic impacts. The primary study site was located 70 km downwind of Manaus, a city of over 2 million people in Brazil, as part of the GoAmazon2014/5 experiment. A high-resolution time-of-flight aerosol mass spectrometer (AMS) provided data on PM₁ composition, and aethalometer measurements were used to derive the absorption coefficient babs,BrC of brown carbon (BrC) at 370 nm. Non-refractory PM₁ mass concentrations averaged 12.2 µg m⁻³ at the primary study site, dominated by organics (83 %), followed by sulfate (11 %). A decrease in babs,BrC was observed as the mass concentration of nitrogen-containing organic compounds decreased and the organic PM₁ O:C ratio increased, suggesting atmospheric bleaching of the BrC components. The organic PM₁ was separated into six different classes by positive-matrix factorization (PMF), and the mass absorption efficiency Eabs associated with each factor was estimated through multivariate linear regression of babs,BrC on the factor loadings. The largest Eabs values were associated with urban (2.04±0.14 m² g⁻¹) and biomass-burning (0.82±0.04 to 1.50±0.07 m²g⁻¹) sources. Together, these sources contributed at least 80 % of babs,BrC while accounting for 30 % to 40 % of the organic PM₁ mass concentration. In addition, a comparison of organic PM₁ composition between wet and dry seasons revealed that only part of the 9-fold increase in mass concentration between the seasons can be attributed to biomass burning. Biomass-burning factor loadings increased by 30-fold, elevating its relative contribution to organic PM₁ from about 10 % in the wet season to 30 % in the dry season. However, most of the PM₁ mass (>60 %) in both seasons was accounted for by biogenic secondary organic sources, which in turn showed an 8-fold seasonal increase in factor loadings. A combination of decreased wet deposition and increased emissions and oxidant concentrations, as well as a positive feedback on larger mass concentrations are thought to play a role in the observed increases. Furthermore, fuzzy c-means clustering identified three clusters, namely “baseline”, “event”, and “urban” to represent different pollution influences during the dry season. The baseline cluster, representing the dry season background, was associated with a mean mass concentration of 9±3 µg m⁻³. This concentration increased on average by 3 µg m⁻³ for both the urban and the event clusters. The event cluster, representing an increased influence of biomass burning and long-range transport of African volcanic emissions, was characterized by remarkably high sulfate concentrations. The urban cluster, representing the influence of Manaus emissions on top of the baseline, was characterized by an organic PM₁ composition that differed from the other two clusters. The differences discussed suggest a shift in oxidation pathways as well as an accelerated oxidation cycle due to urban emissions, in agreement with findings for the wet season.
dc.description.sponsorshipThis research has been supported by the Atmospheric Radiation Measurement (ARM) Climate Research Facility, a user facility of the United States Department of Energy (DOE, DE-SC0006680), Office of Science, sponsored by the Office of Biological and Environmental Research, and support from the Atmospheric System Research (ASR, DE-SC0011115, DE-SC0011105) program of that office. Additional funding was provided by the Amazonas State Research Foundation (FAPEAM 062.00568/2014 and FAPEAM 134/2016), the São Paulo State Research Foundation (grant nos. FAPESP 2013/05014-0, FAPESP 2017/17047-0, FAPESP 2013/50510-5, and FAPESP 2013/10156-8), the US National Science Foundation (grant nos. 1106400 and 1332998), and the Brazilian Scientific Mobility Program (CsF/CAPES). Brett B. Palm, Pedro Campuzano-Jost, Douglas A. Day, and Jose L. Jimenez were supported by DOE (BER/ASR (grant no. DE-SC0016559) and NSF (grant no. AGS-1822664)).
dc.description.urihttps://acp.copernicus.org/articles/19/7973/2019/
dc.format.extent29 pages
dc.genrejournal articles
dc.identifierdoi:10.13016/m2i3x7-rkzh
dc.identifier.citationSá, Suzane S. de, Luciana V. Rizzo, Brett B. Palm, Pedro Campuzano-Jost, Douglas A. Day, Lindsay D. Yee, Rebecca Wernis, et al. “Contributions of Biomass-Burning, Urban, and Biogenic Emissions to the Concentrations and Light-Absorbing Properties of Particulate Matter in Central Amazonia during the Dry Season.” Atmospheric Chemistry and Physics 19, no. 12 (June 18, 2019): 7973–8001. https://doi.org/10.5194/acp-19-7973-2019.
dc.identifier.urihttps://doi.org/10.5194/acp-19-7973-2019
dc.identifier.urihttp://hdl.handle.net/11603/34802
dc.language.isoen_US
dc.publisherEGU
dc.relation.isAvailableAtThe University of Maryland, Baltimore County (UMBC)
dc.relation.ispartofUMBC Physics Department
dc.rightsThis work was written as part of one of the author's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law.
dc.rightsPublic Domain
dc.rights.urihttps://creativecommons.org/publicdomain/mark/1.0/
dc.titleContributions of biomass-burning, urban, and biogenic emissions to the concentrations and light-absorbing properties of particulate matter in central Amazonia during the dry season
dc.typeText
dcterms.creatorhttps://orcid.org/0000-0002-4027-1855

Files

Original bundle
Now showing 1 - 2 of 2
Thumbnail Image
Name:
acp1979732019.pdf
Size:
11.14 MB
Format:
Adobe Portable Document Format
Download
Thumbnail Image
Name:
acp1979732019supplement.pdf
Size:
3.71 MB
Format:
Adobe Portable Document Format
Download

Collections

UMBC Physics Department