Publication Date:
2015-11-25
Description:
Five sites were selected to investigate the impact of regional-scale air pollutant control strategies during the Asia–Pacific Economic Cooperation (APEC) conference (November 1–12, 2014) in and around Beijing. Concentrations of most of the air pollutants in the APEC period were significantly lower than those in the adjacent time period, especially when the enhanced reduction measures were implemented. Compared with the same time period in the previous five years (PM 2.5 was compared with the last year), average concentrations of SO 2 , NO 2 , PM 10 , and PM 2.5 in the five sites during the APEC period decreased by 62%, 41%, 36% and 47% respectively, whereas average concentration of O 3 increased by 102%. A possible cause of the increase of O 3 concentrations is the stricter reduction measure on NO x compared to that applied to volatile organic compounds (VOCs). Compared with the non-APEC period in autumn 2014, concentrations of most of the chemical compositions of PM 2.5 decreased significantly in the APEC period, especially SO 4 2− , NO 3 − , and NH 4 + (Sulfate, nitrate and ammonium, SNA). The aerosol optical depth (AOD) and the columnar NO 2 in the area of 39.5°-40.5°N, 116°–117°E showed a changing pattern similar to the typical gas pattern. The net effectiveness of the emission reduction measures was calculated through a comparison of concentrations of air pollutants under similar meteorological conditions. Through the reduction measures imposed during the APEC period, concentrations of CO, SO 2 , NO, NO 2 , PM 10 and PM 2.5 , decreased by 54%, 74%, 64%, 48%, 67%, and 65%, respectively, whereas concentrations of O 3 increased by 189%.
Print ISSN:
0148-0227
Topics:
Geosciences
,
Physics
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