Spatio-temporal variations of sulphur dioxide patterns with wind conditions in central Taiwan

Sulphur dioxide (SO2) is one of the main atmospheric pollutants in central Taiwan. This article analyses the SO2 concentration seasonal variations and spatial distribution using data obtained from ten air quality monitoring stations and the Taiwan Weather Bureau. It reveals that SO2 concentration is high in winter and low in summer and that high concentration centers are located south of the Taichung coal-fired power plant, the main source of SO2 emissions in the region. The location of high concentration centers changes with different prevailing winds. SO2 variations due to wind direction are not unique. During short periods, when meteorological conditions are constant, variation in the pollution sources cause variations in the spatial distribution. This has been deduced by appreciation of `Intervention analysis' to time series of hourly data.