Analysis of Air Pollution Index and Its Influence Factors in Beijing

Based on Data of Air Pollution Index( API) and meteorological data of Beijing from 2001 to 2012,the paper analyzed the trend and influence factors of Beijing's API through descriptive statistics and generalized linear model( GLM). Analysis results indicated that,the air quality was better and better in the observed period generally. API varied seasonally,which was higher in spring and winter and was lower in summer. Meteorological variables have significant effects on air quality. Air pressure,temperature,precipitation and duration of sunshine negatively correlated with API,while daily maximum temperature,humidity and wind speed positively correlated with API. The policy of traffic control did improve air quality,while no significant weekend effect was found.