Drivers of Air Quality in the East Mediterranean

Abstract

Due to its location and the particularly warm and sunny climate, the East Mediterranean is receptor and chemical cooker of transported air pollution. Main local anthropogenic sources in the region are from traffic, combustion and energy generation concentrated in the large urban agglomerations in the region. These megacities local pollution emissions are added to high background regional air pollutant levels that are due to long range transport from upwind pollution or dust sources and to interactions of transported air masses with regional natural and anthropogenic emissions. Air quality in the East Mediterranean is strongly affected by sources other than the local anthropogenic sources. Thus, inter-country influences and natural contributions need to be documented. Improvement in air quality in the East Mediterranean requires coordinated effort between the countries surrounding the basin as well as the upwind located countries since their emissions affect the basin via long range transport and chemical aging of air masses. Our results clearly demonstrate significant imports of pollutants to the boundary layer via long range transport within the free troposphere followed by subsidence to the boundary layer. The impact of hot spot emissions in the area and its evolution in a warmer climate are evaluated and discussed.