The potential for long-range transport of air-pollutants into Greece: a climatological analysis.

A flow climatology using 5 years (1983-1987) of back trajectories has been created for the Aliartos meteorological-chemical station (Greece's EMEP-station phi = 38 degrees 13'N, lambda = 23 degrees 00'E) using the Air Resources Laboratory (ARL) trajectory model. Air mass back trajectories were analysed to quantify the contributions of major source areas to the air pollution concentration in the area of Greece. The trajectories were produced two times a day at the 850-hPa and 700-hPa pressure surface. The trajectories were classified and summarised in order to produce a long range trajectory climatology. The purpose of this paper is to use the above flow climatology to improve understanding to atmospheric transport pathways to Greece (and to the greater south-eastern area of Europe) and to evaluate the polluting potential of distant source regions outside the country. The limited chemical concentration data available from Aliartos are used to evaluate the conclusions reached from the flow climatology and emissions analysis. The results show that trajectories reach Greece from five major source areas: (i) Northwest Europe, (ii) west Europe, (iii) north Europe, (iv) Northwest Asia, and (v) Northwest Africa. Sector analysis of air pollution concentrations and emissions also showed that: (i) Most air pollutants transport from distances beyond 1800 km takes place, and the most probable source areas are the industrialised countries of Europe. (ii) Countries of west and north-central Europe emit the greater amounts of air pollutants (S and N). (iii) Sulphate and nitrate concentrations are similar among transport sectors.