The influence of long-range transport on increasing tropospheric ozone pollutions in Taiwan was identified by using an objective weather type classification scheme and spatial compositing analysis during the 1994-2004 period. The results of weather type classification show that the occurrence of high ozone pollution episodes is especially associated with the anticyclone type, the anticyclonic easterly type and the north-easterly. The features of these three specific weather types suggest that high ozone pollution episodes over Taiwan were affected by long-range pollutant transport due to the inflows from China, Korea and Japan accompany with high ozone concentrations. The results of spatial compositing analysis also prove the mechanism of long-range transport is related to the large-scale atmospheric circulation. During spring and autumn period, extension of the Siberia High over China accumulates pollutants both from rural and industrial areas, and along the eastern border substantial ozone precursors and pollutants from the area of divergence and northern industrial areas can be transported downward to Taiwan. This suggests that the change of atmospheric circulation, which is caused by global warming, could influence tropospheric ozone pollution over Taiwan, or even East Asia region, in the future, as this pressure pattern is associated with the changes in the monsoon circulation.
AGU Fall Meeting Abstracts
- Pub Date:
- December 2007
- 0368 Troposphere: constituent transport and chemistry