BEIJING AIR QUALITY ANALYSIS OF TIME-VARYING CHARACTERISTICS

Taking Beijing city as an example,it is studied and analyzed the air quality in daily reports(including primary pollutants,pollution index,air quality levels and the air quality status,etc.) between 2000 and 2004 in this paper,then conclude the change characteristics of the year and the month,and the distribution characteristics of the moderate severe pollution day.The results show that the pollution was quite serious in 2001 and 2002 in Beijing which the average pollution index(API) was 113 and 112 respectively.During one year,the pollution in winter was more serious,especially in December and January.This is closely related to the energy structure of Beijing.The most days of moderate severe pollution was in 2001 which was up to 23 days;the maximum days of moderate severe pollution days sustained eight days which was in April 2002;heavy contamination usually occurred in March,April and November.The primary pollutant of Beijing is the inhalable particulate.