LONG-RANGE TRANSPORTED AIR POLLUTANTS FROM CONTINENTAL AREAS TO THE REMOTE REGION OF THE NORTH AEGEAN SEA

摘要

Long-range transportation of air pollutants from industrial and urban environments can significantly affect the climate in remote regions. In this study, we investigate the transportation of pollutants to the remote environment of the North Aegean Sea (NAS) during the summer period, when the synoptic Etesian wind conditions prevail. A temporary monitoring station was assembled at a remote region on the island of Lemnos, which is located at the center of the NAS at a distance of ca. 250 km from the continent. The observed number concentration of particles in the nucleation mode increased almost four fold while their size decreased to 20 nm when the winds had a north-eastern direction. During these pollution transport events we also observed enhanced concentrations of nucleation mode particles that grew in size with a rate that ranged from 4.6 to 8.0 nm h~(-1). Corresponding back-trajectory calculations show that the air masses arriving at our station had passed over the wider industrial region of Marmara and Istanbul ca. 9 to 12 hours prior. This is long enough time for newly formed particles to grow up to the climate relevant size of ca. 20 nm at which they are observed. Our data provide evidence that the atmospheric aerosol in the remote region of the NAS can be significantly affected by emissions from the northeastern industrial and urban areas during the summer period.