Dynamic analysis on air pollution index in Wuhan city between 2001 and 2010

ObjectiveTo analyze dynamic trend of air pollution index (API) in Wuhan city from 2001 to 2010. MethodsDaily API data were collected from the daily report of API in Wuhan city between 2001 to 2010 published by the Ministry of Environment Protection of the People's Republic of China and Wuhan Municipal Enviromment Protection Bureau. ResultsThe annual average API in Wuhan city decreased gradually between 2001 to 2010.A decrease in annual average API from 101 in 2001 to 78 in 2010 was observed.The annual average inhalable particulate matter (particulate matter less than 10 μm in aerodynamic diameter PM10) also decreased from 105 in 2001 to 78 in 2010.The annual average sulfur dioxide (SO₂) and nitrogen dioxide (NO₂) levels were mainly steady.PM10 was one of the principal pollutants in the ambient air of the city,followed by sulfur dioxide.The numbers of days with grade II air quality was the greatest in summer and the least in winter. ConclusionOver the past ten years,air quality in Wuhan city was significantly improved.PM10 and SO₂ should be controlled to further improve the quality of ambient air in Wuhan city.