Articles | Volume 14, issue 9
Atmos. Chem. Phys., 14, 4793–4807, 2014

Special issue: The Pan European Gas-Aerosols Climate Interaction Study...

Atmos. Chem. Phys., 14, 4793–4807, 2014

Research article 14 May 2014

Research article | 14 May 2014

Processing of biomass-burning aerosol in the eastern Mediterranean during summertime

A. Bougiatioti1,2, I. Stavroulas3, E. Kostenidou4, P. Zarmpas3, C. Theodosi3, G. Kouvarakis3, F. Canonaco5, A. S. H. Prévôt5, A. Nenes1,4,6, S. N. Pandis4,7, and N. Mihalopoulos3,4,8 A. Bougiatioti et al.
  • 1School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, USA
  • 2National Technical University of Athens, Laser Remote Sensing Laboratory, Zografou, Greece
  • 3Environmental Chemical Processes Laboratory, University of Crete, 71003 Crete, Greece
  • 4Institute of Chemical Engineering Sciences (ICE-HT), FORTH, Patras, Greece
  • 5Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
  • 6School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, USA
  • 7Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, USA
  • 8Institute for Environmental Research and Sustainable Development, National Observatory of Athens, 15236, Athens, Greece

Abstract. The aerosol chemical composition in air masses affected by wildfires from the Greek islands of Chios, Euboea and Andros, the Dalmatian Coast and Sicily, during late summer of 2012 was characterized at the remote background site of Finokalia, Crete. Air masses were transported several hundreds of kilometers, arriving at the measurement station after approximately half a day of transport, mostly during nighttime. The chemical composition of the particulate matter was studied by different high-temporal-resolution instruments, including an aerosol chemical speciation monitor (ACSM) and a seven-wavelength aethalometer. Despite the large distance from emission and long atmospheric processing, a clear biomass-burning organic aerosol (BBOA) profile containing characteristic markers is derived from BC (black carbon) measurements and positive matrix factorization (PMF) analysis of the ACSM organic mass spectra. The ratio of fresh to aged BBOA decreases with increasing atmospheric processing time and BBOA components appear to be converted to oxygenated organic aerosol (OOA). Given that the smoke was mainly transported overnight, it appears that the processing can take place in the dark. These results show that a significant fraction of the BBOA loses its characteristic AMS (aerosol mass spectrometry) signature and is transformed to OOA in less than a day. This implies that biomass burning can contribute almost half of the organic aerosol mass in the area during periods with significant fire influence.

Final-revised paper