Atmospheric aerosols and gases in rural Nova Scotia and their dependence on air flow

Various species including nitrate, HN0₃ and Pb were sampled in Antigonish, Nova Scotia and their fluctuations were compared to those of simultaneously sampled acid and sulphate (reported previously). The 24 hr average aerosol nitrate, ～0.3 μg m^?3, was similar in the summer and winter. Nitric acid made up ～42 % of the total (aerosol and gaseous) nitrate in the summer and winter, but nitrate and HN0₃ were correlated only in the summer. Windroses are used to show the dependence of sulphate, nitrate and aerosol acid on wind direction. Lead had a 24 hr average concentration of 71 ng m^?3, was of mainly local origin and was not able to be correlated with other parameters.