APEC区域减排对北京PM_(2.5)浓度时空变化的影响分析

Impact of APEC Regional Emission Reduction on Spatio-Temporal Variation of PM_(2.5) Concentration in Beijing

为保障2014年亚太经济合作组织(APEC)会议期间北京的空气质量,京津冀晋鲁豫(简称J4LY地区)采取了区域减排措施。该文基于地基监测的PM_(2.5)日均浓度数据,利用普通克里金方法对该地区的PM_(2.5)进行空间插值表达,分析其时空分布特征,并顾及风速、相对湿度评估区域减排对研究区空气质量的影响。与2013年同期相比,虽然APEC期间气象条件不利,北京PM_(2.5)浓度仍下降28%。APEC会后区域减排措施解除,京津冀空气质量急剧转差、PM_(2.5)浓度反弹,凸显了区域减排措施的重要性。采用Spearman秩相关系数,分析对比了2014年APEC前后共34d与2013年、2015年同期北京与周边城市PM_(2.5)浓度相关性的变化特征,揭示区域减排措施有效降低了山东、河南空气污染物的远程传输贡献。

In order to guarantee Beijing′s air quality during the Asia-Pacific Economic Cooperation（APEC）Summit on Nov.5-11,2014,several provinces including Beijing（Jing）,Tianjin（Jin）,Hebei（Ji）,Shanxi（Jin）,Shandong（Lu）and Henan（Yu）,named in general J4 LY region,had taken temporary regional emission reduction measures（RERMs）.Based on ground measurements on PM2.5concentration,this paper applied ordinary Kriging method to do spatial interpolation and make comparison analysis in J4 LY region.We analyzed the spatio-temporal variation characteristics of PM2.5concentration and assessed the impact of RERMs on Beijing PM2.5.Referring to wind speed and relative humidity and compared with the same period in 2013,although the meteorological conditions in Beijing appeared adverse during the APEC,Beijing PM2.5concentration still declined by 28%.The air quality of J4 LY got deteriorated rapidly as the RERMs being lifted after APEC summit,which verified again RERMs is very effect and important.Using Spearman rank correlation analysis and comparing the APEC-related period（34d）with the same period in 2013 and 2015,respectively,the correlations of PM2.5concentrations between Beijing and other cities in J4 LY region were analyzed.The results indicate further the RERMs had reduced also the long-distance transmission of air pollutants from Shandong and Henan to Beijing.