Study of the Pollution Exchange between Bulgaria and Northern Greece

The present work aims at a detailed study and explanation of the pollution transport in the air basin over South-westem Bulgaria and Northem Greece and assessment of the air pollution exchange between Bulgaria and Greece. Some weli known specific climatic air poilution effects were studied and explained. Calculations were made ofthe S02 poilution ofthe Balkan peninsula from both Greek and Buigarian sources for 1995 and the country to country pollution budget diagrams were build. Days with extreme mean concentration for Buigaria and Northern Greece were picked out and some further specification of the contribution of the different sources in both the countries to these cases ofextreme po!Iution was made. Some preliminary studies of possibie mesoscaie effects on the pollution exchange between Bulgaria and northern Greece were carried out. A three-layer pollution transport model with more complex chemistry block was introduced and some preliminary simulations of Sulfur and Nitrogen compounds transport were performed. Ob jectives The present work aims at a detaiied study and explanation of the pollution transport in the air basin over South-western Bulgaria and Northern Greece and assessment of the air pollution exchange between Bulgaria and Greeee. Research methods and techniques The air pollution studies and the following assessments were based on reliable and representative data: BREWER and DOAS air pollution data from Thessaioniki since 1982; detailed synoptic information for the Balkan peninsula since 1994; detailed emission inventory, based on the CORlNAIR methodology since 1990; information from ground-based air pollution measuring stations Extensive computer simulations were carried out and the conclusions were made on the basis of joint anaiysis of data and simuiation results. Main results A specific climatic effect was registered in the city of Thessaloniki by analysis of the time series obtained by the 1 5 year Brewer spectrophotometer measurements of the columnar S02 although the maximum concentrations of columnar S02 originate form local sources in the winter, sign[ficant columnar S02 amounts are aiso seen in the summer, when there are no locai sulfur sources. On a few occasions however, as high as 5-7 m-atm-cm of columnar S02 have been measured both in winter and summer period. The nature of this phenomena was studied for selected episodes [1 J and for July, August 1994 [2]. ~~'~ 6 [ epis~ 1 5 4r 3[ :[ ~ ~ o f ~~~' 211 2i2 213 ~. ~~~~~ 214 ~ 217 21 8 ~ ~,_,