Influences of ambient air pollutants and meteorological conditions on ozone variations in Kaohsiung, Taiwan
- 356 Downloads
The complex process of ozone formation, its precursor compounds (volatile organic compounds (VOCs) and nitrogen oxides (NOx)) emissions, accompanying with meteorological conditions, makes troposphere ozone difficult to control. This study applies dynamic factor analysis (DFA) to investigate the time series of ambient ozone concentrations and their associations with meteorological variables. The analyses were applied on the hourly data collected at the four monitoring stations in Kaohsiung (Taiwan) during the 72-h periods with three events in high and low ozone episodes in 2009. According to the optimal DFA model, NOx negatively control ozone variations in all events. Relative humidity (RH) only negatively influences the ozone fluctuations in low ozone episode. The sea–land wind speed (i.e. west direction) and air temperature positively affect ozone fluctuations in high ozone episode. CO significantly influences ozone fluctuations in main city area for high ozone episode and in all stations for low ozone episode. However, VOC did not significantly correlate with ozone fluctuations for both ozone episodes. The results show that ozone conditions of both episodes were in NOx-saturated regimes, where increased NOx would result in lower ozone. Temperature, RH, and sea–land wind speed can be treated as metrological variables, which significantly vary the concentrations of surface-level ozone. This study shows DFA can provide a quantitative insight into the temporal variations of CO, NOx, and meteorological conditions effects on ozone variations that will be a reference to air quality management in the study area.
KeywordsDynamic factor analysis Volatile organic compounds Sea–land wind Nitrogen oxides Carbon monoxide NOx-saturated
The authors would like to thank the National Science Council of Taiwan, for financially supporting this research under Contract No. NSC 101-2313-B-451-003, NSC101-2628-E-002 -017 -MY3 and NSC 102-2221-E-002-140-MY3, and thank the Taiwan Environmental Protection Administration (TWEPA) for providing the monitoring data.
- Barros N, Toll I, Soriano C, Jiménez P, Borrego C, Baldasano JM (2003) Urban photochemical pollution in the Iberian peninsula: the Lisbon and Barcelona airsheds. J Air Waste Manag Assoc 53:347–359Google Scholar
- Hastie DR, Narayan J, Schiller C, Niki H, Shepson PB, Sills DML, Taylor PA, Moroz WJ, Druummond JW, Reid N, Taylor R, Roussel PB, Melo OT (1999) Observational evidence for the impact of the lake breeze circulation on ozone concentrations in Southern Ontario. Atmos Environ 33:323–335CrossRefGoogle Scholar
- Highland Statistics (2000) Software package for multivariate analysis and multivariate time series analysis Version 2. Highland Statistics, Ltd., Newburgh, UKGoogle Scholar
- Kambezidis HD, Weidauer D, Melas D, Ulbricht M (1998) Air quality in the Athens Basin during sea breeze and non-sea breeze days using laser-remote-sensing technique. Atmos Environ 32:2173–2182Google Scholar
- Seinfeld JH, Pandis SN (2006) Atmospheric chemistry and physics—from air pollution to climate change, 2nd edn. Wiley, New YorkGoogle Scholar
- Sillman S (1999) The relation between O3, NOx and hydrocarbons in urban and polluted rural environments. Atmos Environ 33:1821–1845Google Scholar
- Swartman RK, Ogunlade O (1967) A statistical relationship between solar radiation’, sunshine and relative humidity in the tropics. Atmosphere 5(2):25–34Google Scholar