摘要
为研究北京市夏季臭氧特征及污染成因,于2017年7月15日至2017年8月10日期间,在北京市城区进行气象要素、臭氧(O3)、氮氧化物(NOx)和一氧化碳(CO)的连续观测,并选取7d(2017年7月20日、30日和8月1日、4~7日)密集采集大气样品进行挥发性有机化合物(VOCs)和含氧挥发性有机化合物(OVOCs)的分析。结果表明,观测期间北京市夏季O3污染严重,臭氧污染日以东南风为主,一般伴随着高温、低湿、低压和高前体物(VOCs、CO和NOx)浓度,占总观测天数的51.8%。密集采样日中臭氧污染日的成因与副热带高压或均压场下的弱高压系统有关。此外,来自河北、内蒙古中部和蒙古国东部途经保定和张家口等地的气流为北京夏季臭氧污染日的形成提供了部分外源,日平均贡献量为16%~37%,最大贡献量为53%,显示区域传输对臭氧污染日形成有重要影响。敏感性试验发现O3的生成主要受VOCs控制,特别是人为源VOCs。以上结果表明,控制北京本地VOCs的人为排放和周边空气质量将有助于降低北京城区的O3浓度。
To investigate the characteristics and causes of ozone (O3) pollution in Beijing, continuous measurements of meteorological parameters, O3, nitrogen oxide (NOx) and carbon monoxide (CO) were conducted at an urban site in Beijing from July 15 to August 10, 2017. In addition, offline one-hour whole air samples were collected on 7 selected days (i.e. 20 and 30 July, and 1 and 4-7 August 2017) to analysis volatile organic compounds (VOCs) and oxygenated VOCs (OVOCs). The results indicated that Beijing suffered from severe O3 pollution, with the O3 episodes accounting for 51.8% of the whole sampling period. In general, high O3 days were associated with high temperature, low relative humidity, low pressure, and high levels of precursors (i.e. VOCs, CO and NOx). On the VOCs sampling days, high O3 episodes were predominantly controlled by the Western Pacific Subtropical High or uniform pressure field (weak high pressure). Furthermore, air masses from Hebei, middle Inner Mongolia and eastern Mongolia, passing by Baoding and Zhangjiakou, partially contributed to the observed O3 in Beijing. The average regional contribution to O3 accounted for 16%-37%, with a maximum of 53%.The sensitivity analysis revealed that O3 formation in Beijing was mainly sensitive to VOCs, especially anthropogenic VOCs (AVOCs). This study indicated that effective control of AVOCs emissions in Beijing and the surrounding cities may help to reduce O3 levels in Beijing.
作者
王佳颖
曾乐薇
张维昊
吕效谱
郭海
傅平青
韩力慧
周颖
WANG Jia-ying;ZENG Le-wei;ZHANG Wei-hao;Lü Xiao-pu;GUO Hai;FU Ping-qing;HAN Li-hui;ZHOU Ying(School of Resource and Environmental Sciences,Wuhan University,Wuhan 430072,China;Department of Civil and Environment Engineering,The Hong Kong Polytechnic University,Hong Kong,China;State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry,Institute of Atmospheric Physics,ChineseAcademy of Sciences,Beijing 100029,China;College of Environment and Energy Engineering,Beijing University of Technology,Beijing 100124,China)
出处
《地球化学》
CAS
CSCD
北大核心
2019年第3期293-302,共10页
Geochimica
基金
国家重点研发计划项目(2017YFC0212001)
香港理工大学和北京工业大学合作研究项目(4-ZZFW)
关键词
臭氧
挥发性有机化合物
区域传输
光化学反应
北京市
ozone
volatile organic compounds
regional transport
photochemical reactions
Beijing city
作者简介
王佳颖(1993–),女,硕士研究生,环境科学专业。E-mail: jiayingking@126.com;通讯作者:张维昊, E-mail: zhangwh@whu.edu.cn;Tel:+86-27-68777060.
