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| Titel |
High temporal resolution measurements of biomass burning events during summertime in the Eastern Mediterranean. |
| VerfasserIn |
Aikaterini Bougiatioti, Pavlos Zarmpas, Christina Theodosi, Iasonas Stavroulas, Giorgos Kouvarakis, Francesco Canonaco, André S. H. Prévôt, Spyros N. Pandis, Nikolaos Mihalopoulos |
| Konferenz |
EGU General Assembly 2013
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 15 (2013) |
| Datensatznummer |
250079321
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| Zusammenfassung |
| Several major wildfires occurred at the Greek islands of Chios, Euboea and Andros during the summer of 2012. The corresponding biomass burning-influenced air masses were studied at the remote background site of Finokalia, Crete. The smoke was transported several hundreds of kilometers, arriving at the measurement station after approximately half a day of atmospheric processing, mostly during night-time. The origin of air masses was confirmed by back-trajectory analyses and the chemical composition of the particulate matter was studied by different high-resolution measurements, including an Aerosol Chemical Speciation Monitor (ACSM), and a seven wavelengths aethalometer. Despite the distance between the islands and the travel time, a clear biomass burning profile containing characteristic markers could be derived from BC measurements and exploiting the statistical tool Multilinear Engine (ME-2).
During these events aerosol particles contained a noteworthy amount of black carbon, ranging from 2.8 up to 5 μg m-3, which exceeds typical background values by a factor of 8 or more. Simultaneously organic matter concentrations increased significantly. In the case of the island of Chios fires the fine PM levels exceeded background values by a factor of 4 ranging from 2.9 to11.6 μg m-3.
PMF is a statistical tool used to deconvolve the organic aerosol spectral matrix measured by the Aerosol Chemical Speciation Monitor (ACSM), resulting in a number of components/factors that are a posteriori validated as possible sources. A successful unconstrained run (PMF) within the Multilinear Engine (ME-2) over the fire events only, lead to a clear biomass burning profile which correlates well with reference biomass burning spectra (R2=0.9). The model was rerun over the entire period by constraining this biomass burning profile and the fire events were all well-represented. More than 70% of the measured OA is “aged”, oxidized organic aerosol, which correlates well with reference OOA spectra (R2=95%). Even if often the smoke was mainly transported overnight, half a day of travel was sufficient for the transformation of freshly-emitted BBOA to more oxidized OOA in the very oxidizing environment of the Eastern Mediterranean. |
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