Basic characteristics of atmospheric particles, trace gases and meteorology in a relatively clean Southern African Savannah environment

The annual-median trace gas concentrations were equal to 0.7 ppb for SO₂, 1.4 ppb for NOx, 36 ppb for O₃ and 105 ppb for CO. The corresponding PM₁, PM₂.₠and PM₁₀ concentrations were 9.0, 10.5 and 18.8 μg m⁻³, and the annual median total particle number concentration in the size range 10–840 nm was 2340 cm⁻³.

During Easterly winds, influence of industrial sources approximately 150 km away from the measurement site was clearly visible, especially in SO2 and NOx concentrations. Of gases, NOx and CO had a clear annual, and SO2, NOx and O3 clear diurnal cycle. Atmospheric new-particle formation was observed to take place in more than 90% of the analyzed days.