大阅兵期间北京市大气质量改善效果评估

Evaluation of the improvement of the air quality during the parade in Beijing

为了评估抗战纪念活动期间污染物减排措施对北京市空气质量的影响,利用2015年8月1日~2015年9月18日北京市大气污染物浓度数据,以及2014年同期监测数据进行对比分析.结果表明:减排期间(2015年8月20日~2015年9月3日)北京市PM_(2.5),SO_2,NO_2和CO浓度均值为17.05μg/m^3,2.35μg/m^3,21.04μg/m^3和0.56mg/m^3,对比减排前期,各污染物分别下降了71.26%,36.49%,37.92%和37.78%,减排后期,随着减排措施的取消,大气污染物反弹上升.与2014年同期相比,减排期间污染物浓度分别下降了73.59%,56.64%,52.39%和38.46%,大气质量改善效果显著.3个时段(减排期间,活动当天和2014年同期)污染物浓度日变化特征相似,整体上呈现2014年同期>减排期间>活动当天的特征.空间分布上,各站点污染物浓度均远低于2014年同期水平,其中PM_(2.5)降幅大且空间差异较小,SO_2在空间上差异最为明显,不同站点的PM_(2.5)降幅在68.91%~77.63%之间,SO_2降幅在7.43%~74.75%之间,NO_2降幅在34.60%~72.28%之间,CO降幅在24.98%~63.73%之间.减排期间北京市PM_(2.5),SO_2,NO_2和CO浓度分别比周边城市均值低24.66%,81.00%,27.30%和36.36%,也从另一方面反映出减排措施的明显效果.

To evaluate the effects of the implementation of emission reduction measures and the revolution of air quality during the 70 th anniversary of victory parade in Beijing, the variation of characteristics of air pollutant was analyzed based on observations of air pollutants at twelve sites in Beijing City from August 1, 2015 to September 18, 2015, and compared with that in 2014. The results showed that： The average concentrations of PM_（2.5）, SO_2, NO_2, CO were 17.05μg/m-3, 2.35μg/m-3, 21.04μg/m-3, 0.56mg/m-3 respectively during emission reduction, the average concentrations of PM_（2.5）, SO_2, NO_2, CO were decreased by 71.26%, 36.49%, 37.92%, 37.78% compared to the period before emission reduction, after the emission reduction, with the cancellation of emission abatement measures, air pollutant showed an upward tendency. Compared with the same time in 2014, the average concentrations of PM_（2.5）, SO_2, NO_2, CO were decreased by 73.59%, 56.64%, 52.39%, 38.46% during emission reduction, air quality improvement was very obvious. Diurnal variation of pollutants were similar, the same time in 2014during emission reductionday of the event. The concentrations of pollutants was well below the same time in 2014 at each monitoring site during emission reduction, the improvement percentage of PM_（2.5） was big and the spatial difference was relatively small, the spatial difference of SO_2 was most obvious, the concentrations of PM_（2.5） at different sites were decreased by 68.91%-77.63%, the concentrations of SO_2 at different sites were decreased by 7.43%-74.75%, the concentrations of NO_2 at different sites were decreased by 34.60%-72.28%, the concentrations of CO at different sites were decreased by 24.98%-63.73%. The average concentrations of PM2.5, SO2, NO2, CO in Beijing was lower than nearly surrounding areas, this further shows that implementation measures had made a great contribution to the improvement of air quality in Beijing during emission reduction.