Seasonal nitrogen dioxide concentrations in atmosphere in Kaunas : Lithuania and its relation with meteorological conditions

Abstract

The aim of the present study was to assess nitrogen dioxide concentrations in Kaunas city and examine its relation with meteorological conditions. We used a passive sampling method and triethanolamine as an absorbent. Sampling was carried out in 104 points of Kaunas city, 4 times per year during 1999-2002 years period. According to measured concentrations average seasonal and annual concentrations in Kaunas districts and in the whole city were calculated. The study results showed that mean NO2 concentration in Kaunas city was 16,5 mu g/m(3). The highest mean seasonal concentration was found during springs (17,4 mu g/m(3)) and the lowest - during autumns (15,2 mu g/m(3)). The highest NO2 concentrations were in the Centre (4 years average - 25,3 mu g/m(3)). We found correlation between nitrogen dioxide concentrations and wind speed (r=-0,5447, p= 0,029), and between nitrogen dioxide concentrations and rainfall (r-- -0,970, p= 0,023). Correlation between nitrogen dioxide concentrations and temperature was non significant (r=0,65 0,811).