AIR-POLLUTION AND INVERSION FEATURES IN ISTANBUL

Air pollution in the Istanbul metropolitan area arises from three sign ificant sources: industrial and residential fossil fuels and road traf fic. In winter this combination pushes air pollution to levels that ar e dangerous to humans and to plant life. As far as fossil fuels are co ncerned, total suspended particulates (TSP) and sulfur dioxide are the chief pollutants. In order to investigate the problem, five-year wint er-season monthly pollution concentration records are used, starting f rom 1989. Classical statistical methods, such as frequency distributio n functions, are examined and found to have exponential (SO2), logarit hmic normal (TSP) and Weibull (inversion height) distributions. A simp le concept of 'pollutant polygon' is presented in order to make detail ed interpretations of the relationship between the monthly averages of SO2 and TSP. These levels were affected by the weak dispersion condit ions in the lower atmosphere over the city.