Air quality in Taiwan is improved because of Taiwan EPA pushed air control strategies positively in recent years. However, public attention on air quality are increasing even its air quality has been constantly being improved in the last decade. The interaction between terrain and atmosphere would affect the efficient control of smog and air pollution. This study discusses the correction between ventilation index (VI) and air quality. Before proceeding to estimate VI, it will be necessary to discuss the relevance between the weather type and the fine particulate matter (PM2.5) pollution in Western Taiwan (heavy population areas) by the Weather Research and Forecasting (WRF) model. The second part moves on to ventilation index (VI) that was analyzed by the height of boundary layer data and wind speed, it could help to understand the trend between VI and air quality index (AQI). We also analysis the causes of air pollution episodes include the flow flied of surface and boundary layer. A total of 37 reports were provided. On the other hand, we made 3 handouts and implemented training programs to the staff of the department of Environmental monitoring and information Management. As mentioned above, the result of this study proposed the ventilation index and improved the process of air quality forecasts.

ventilation index, weather type, air quality, air pollution