Seasonal and diurnal characteristics of atmospheric carbonyls in Nanning, China

For the first time, atmospheric carbonyls were measured to identify seasonal and diurnal variations in Nanning from October 2011 to July 2012. Formaldehyde (6.79 +/- 339 mu g/m(3)), acetaldehyde (15.81 +/- 10.48 mu g/m(3)) and acetone (5.43 +/- 6.91 mu g/m(3)) were the three most abundant carbonyls, accounting for similar to 85% of the total carbonyls. The average total concentrations of carbonyls and three abundant carbonyls showed significant high levels in summer compared to those in winter. Diurnal variations suggested that photochemical conditions, combustion of charcoal and straw, and solvent usage are important for the distributions of atmospheric carbonyls. The highest average C-1/C-2 ratio was observed in summer (0.75) compared to those (031-0.70) in other seasons, implying the positive effect of photochemical activities on raising C-1/C-2 ratio, and the significant low C-2/C-3 ratio (12.01-18.23) in winter and autumn than those (95.83-24.49) in both spring and summer suggested the important anthropogenic emissions such as charcoal and biomass combustion. O-3 formation potentials in summer and spring were significantly higher by similar to 2 times than those in autumn and winter. Formaldehyde and acetaldehyde are the top two carbonyls which contribute 82-97% to total O-3 formation potentials. (C) 2015 Elsevier B.V. All rights reserved.