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| Titel |
Aged organic aerosol in the Eastern Mediterranean: the Finokalia Aerosol Measurement Experiment – 2008 |
| VerfasserIn |
L. Hildebrandt, G. J. Engelhart, C. Mohr, E. Kostenidou, V. A. Lanz, A. Bougiatioti, P. F. DeCarlo, A. S. H. Prévôt, U. Baltensperger, N. Mihalopoulos, N. M. Donahue, S. N. Pandis |
| 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 ; 10, no. 9 ; Nr. 10, no. 9 (2010-05-05), S.4167-4186 |
| Datensatznummer |
250008421
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| Publikation (Nr.) |
 copernicus.org/acp-10-4167-2010.pdf |
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| Zusammenfassung |
| Aged organic aerosol (OA) was measured at a remote coastal site on the
island of Crete, Greece during the Finokalia Aerosol Measurement
Experiment-2008 (FAME-2008), which was part of the EUCAARI intensive
campaign of May 2008. The site at Finokalia is influenced by air masses from
different source regions, including long-range transport of pollution from
continental Europe. A quadrupole aerosol mass spectrometer (Q-AMS) was
employed to measure the size-resolved chemical composition of non-refractory
submicron aerosol (NR-PM1), and to estimate the extent of oxidation of
the organic aerosol. Factor analysis was used to gain insights into the
processes and sources affecting the OA composition. The particles were
internally mixed and liquid. The largest fraction of the dry NR-PM1
sampled was ammonium sulfate and ammonium bisulfate, followed by organics
and a small amount of nitrate. The variability in OA composition could be
explained with two factors of oxygenated organic aerosol (OOA) with
differing extents of oxidation but similar volatility. Hydrocarbon-like
organic aerosol (HOA) was not detected. There was no statistically
significant diurnal variation in the bulk composition of NR-PM1 such as
total sulfate or total organic aerosol concentrations. However, the OA
composition exhibited statistically significant diurnal variation with more
oxidized OA in the afternoon. The organic aerosol was highly oxidized,
regardless of the source region. Total OA concentrations also varied little
with source region, suggesting that local sources had only a small effect on
OA concentrations measured at Finokalia. The aerosol was transported for
about one day before arriving at the site, corresponding to an OH exposure
of approximately 4×1011 molecules cm−3 s. The constant
extent of oxidation suggests that atmospheric aging results in a highly
oxidized OA at these OH exposures, regardless of the aerosol source. |
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