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| Titel |
Effects of aging on organic aerosol from open biomass burning smoke in aircraft and laboratory studies |
| VerfasserIn |
M. J. Cubison, A. M. Ortega, P. L. Hayes, D. K. Farmer, D. Day, M. J. Lechner, W. H. Brune, E. Apel, G. S. Diskin, J. A. Fisher, H. E. Fuelberg, A. Hecobian, D. J. Knapp, T. Mikoviny, D. Riemer, G. W. Sachse, W. Sessions, R. J. Weber, A. J. Weinheimer, A. Wisthaler, J. L. Jimenez |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1680-7316
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| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 11, no. 23 ; Nr. 11, no. 23 (2011-12-05), S.12049-12064 |
| Datensatznummer |
250010237
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| Publikation (Nr.) |
 copernicus.org/acp-11-12049-2011.pdf |
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| Zusammenfassung |
| Biomass burning (BB) is a large source of primary and secondary organic
aerosols (POA and SOA). This study addresses the physical and chemical
evolution of BB organic aerosols. Firstly, the evolution and lifetime of BB
POA and SOA signatures observed with the Aerodyne Aerosol Mass Spectrometer
are investigated, focusing on measurements at high-latitudes acquired during
the 2008 NASA ARCTAS mission, in comparison to data from other field studies
and from laboratory aging experiments. The parameter f60, the ratio of
the integrated signal at m/z 60 to the total signal in the organic component
mass spectrum, is used as a marker to study the rate of oxidation and fate
of the BB POA. A background level of f60~0.3% ± 0.06% for
SOA-dominated ambient OA is shown to be an appropriate background level for
this tracer. Using also f44 as a tracer for SOA and aged POA and a
surrogate of organic O:C, a novel graphical method is presented to
characterise the aging of BB plumes. Similar trends of decreasing f60
and increasing f44 with aging are observed in most field and lab
studies. At least some very aged BB plumes retain a clear f60 signature.
A statistically significant difference in f60 between highly-oxygenated
OA of BB and non-BB origin is observed using this tracer, consistent with a
substantial contribution of BBOA to the springtime Arctic aerosol burden in
2008. Secondly, a summary is presented of results on the net enhancement of
OA with aging of BB plumes, which shows large variability. The estimates of
net OA gain range from ΔOA/ΔCO(mass) = −0.01 to ~0.05,
with a mean ΔOA/POA ~19%. With these ratios and
global inventories of BB CO and POA a global net OA source due to aging of
BB plumes of ~8 ± 7 Tg OA yr−1 is estimated, of the order
of 5 % of recent total OA source estimates. Further field data following
BB plume advection should be a focus of future research in order to better
constrain this potentially important contribution to the OA burden. |
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