Seasonal variation of saccharides and furfural in atmospheric aerosols at a semi-urban site

Abstract

Seasonal variability of daily particle mass and saccharides and furfural concentrations in atmospheric particulate matter in both coarse aerosols (diameter > 2.4 μm) and fine aerosols (diameter < 2.4 μm) was determined for a semi-urban area in the United Kingdom. Saccharides, which include levoglucosan, and furfural are derived from biomass burning and contribute to aerosol composition. This study examined the potential of saccharides and furfural as tracers for biomass combustion. High saccharide concentrations were observed in the autumn, but they did not show a high correlation with potassium expected in biomass smoke. These results may imply that the high saccharide concentrations are derived not only from biomass burning sources, but also from non-combustion sources, such as leaf decay. Significant seasonal variations were observed for saccharides and furfural species in fine atmospheric aerosols. Furfural is likely to be oxidized quickly in comparison with saccharides, so while saccharides such as levoglucosan are known to be fairly stable in the atmosphere, furfural could be transformed. Trajectory and factor analysis suggest that the saccharides may result from long-range transport, while furfural may be more influenced by the local sources possibly because of its shorter lifetime. This result may suggest it could give clues as to the age of biomass smoke.