Influences of ambient air pollutants and meteorological conditions on ozone variations in Kaohsiung, Taiwan
Journal
Stochastic Environmental Research and Risk Assessment
Journal Volume
29
Journal Issue
3
Pages
1037-1050
Date Issued
2014
Author(s)
Abstract
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. © 2014, Springer-Verlag Berlin Heidelberg.
Subjects
Carbon monoxide; Dynamic factor analysis; Nitrogen oxides; NOx-saturated; Sea–land wind; Volatile organic compounds
Other Subjects
Air pollution control; Air quality; Carbon monoxide; Factor analysis; Multivariant analysis; Nitrogen oxides; Quality management; Time series analysis; Volatile organic compounds; Wind; Ambient ozone concentration; Dynamic factor analysis; Meteorological condition; Meteorological variables; Monitoring stations; NOx-saturated; Ozone fluctuations; Precursor compounds; Ozone
Type
journal article