The Impact of Wind Conditions on Particle Mass Concentrations in Athens, Greece

The aim of this study was to identify and quantify the effect of wind conditions (direction and speed) on the levels and variation of particulate matter. Daily PM10 and PM2.5 samples were collected for 26 months (from October 2002 to December 2004) in an urban background site in Athens urban area, Greece. Harvard impactors were used to collect atmospheric particles on 37-mm Teflon filters. Particle mass was determined using analytical microbalance with precision of 1 μg. Meteorological data were obtained by the National Observatory of Athens station at Thissio. The relationships between PM10, PM2.5, PM10−2.5 and wind conditions were analyzed using multivariate linear regression of PM concentrations against categorized wind conditions (direction and speed) for the non-rainy days during the study period. Significant fractions of PM10 and PM2.5 mass concentrations were associated with low wind conditions blowing from south. Moderate correlations were observed between PM10 (and PM2.5), and higher wind speeds. Conversely, coarse particles were poorly related to wind conditions although, they represent the majority of PM10 mass, indicating the possible contribution of non-wind related sources.