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Atmos. Chem. Phys. Discuss., 10, 14209-14239, 2010
www.atmos-chem-phys-discuss.net/10/14209/2010/ doi:10.5194/acpd-10-14209-2010 © Author(s) 2010. This work is distributed under the Creative Commons Attribution 3.0 License. |
Occurrence of gas phase ammonia in the area of Beijing (China)
1CNR - Institute of Atmospheric Pollution Research, Via Salaria Km 29.3, CP10, 00015 Monterotondo S., Rome, Italy
2State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China
Abstract. The atmospheric concentrations of gaseous ammonia have been measured during two field campaigns in the winter and in the summer of 2007 at Beijing (China). These measurements were carried out by means of diffusion annular denuders coated with phosphorous acid. The results were discussed from the standpoint of seasonal and diurnal variations and meteorological effects. The daily average NH3 concentrations were in the range of 0.20–44.38 μg/m3 and showed regular seasonal variations with higher concentrations during summer and with lower during winter. The seasonal trends seemed to be largely affected by air temperature because of agricultural sources. No diurnal variability was observed for gaseous NH3 levels in both winter and summer seasons. The highest ammonia value of 105.67 μg/m3 was measured in the early morning during the summer period when stable atmospheric conditions occurred. The diurnal winter and summer trends of ammonia were nearly independent on the air temperatures but they were affected by wind direction suggesting a strong local source influences. Ammonia was also correlated with the atmospheric mixing in the boundary layer, and, with NOx and CO air concentrations supporting the hypothesis that the traffic may be also an important source of ammonia in Beijing.
Citation: Ianniello, A., Spataro, F., Esposito, G., Allegrini, I., Rantica, E., Ancora, M. P., Hu, M., and Zhu, T.: Occurrence of gas phase ammonia in the area of Beijing (China), Atmos. Chem. Phys. Discuss., 10, 14209-14239, doi:10.5194/acpd-10-14209-2010, 2010.