||The air quality of Kao-Ping Air Basin has been the worst among seven airbasins in Taiwan. The percentage of annual air quality that Pollution Standard Index (PSI) exceeded 100 in Kao-Ping Air Basin was 42.80%, which was twice of that in Yun-Chia-Nan Air Basin (23.21%) during the past decade (2006–2015). |
Simulations of surface ozone variations using TAPM model were performed for the spring (March, 2013), summer (August, 2013) and winter (January, 2014) cases in southern Taiwan during which high pressure prevailed with poor atmospheric diffusion. Simulation results reveal that the downwind site in Pingtung County experienced polluted plumes in the spring when a northerly or northeasterly wind prevailed, demonstrating the cross-regional transport of pollutants. The corresponding concentration contours of ozone concentration were high of approximately 90–105 ppb at Pingtung County. Simulations of hourly ozone concentrations agree well with measurements. Predictions of hourly ozone concentrations reveal that high ozone concentrations occurred in the period around 11:00–15:00, while measured ozone concentrations during night and early morning were often lower than the model background concentrations at 10 ppb. Although predictions of model were in some cases higher or lower than measurements, simulated values were generally in agreement with measured values, with a correlation coefficient of R = 0.913, and an index of agreement (IOA)=93.9%.
Reduction VOC/NOX suggest that peak ozone concentration in the spring case can be reduced by 10% by reducing VOC emissions by 9.38–12.10% and NOx emissions by 17.39–27.50%. Sensitivity analyses suggest that reducing emissions of VOC is more effective in lowering the ambient ozone concentration than is reducing emissions of NOx. In Kao-Ping area, the predominant contributors of VOC emissions were manufacturing industries (13.26–40.70%) and living activities (31.58–63.58%), and the predominant contributors of NOx emissions were mobile sources (25.90–59.00%).