G20峰会期间长三角区域臭氧变化及管控效果评估

为了研究2016年二十国集团领导人峰会(G20峰会)期间长三角区域臭氧(O3)变化特征,评估管控措施对O3浓度的影响,利用2016年8月10日至9月20日杭州及周边地区的空气质量监测数据、气象数据以及排放清单数据,分析了O3和NO2浓度及气象条件的时空分布特征,研究了不同管控区域不同保障时期O3浓度的时空变化和O3敏感控制区的改变。结果表明:峰会保障期间对于一次排放污染物和细颗粒物的管控措施效果明显,但核心区的O3质量浓度高于严控区和管控区,分别高出11. 2、9. 2μg/m^3。日间的NOx管控导致O3日变化幅度增高接近50μg/m^3。在峰会保障期间,卫星数据和站点观测结果显示核心区O3由VOCs控制区转为NOx-VOCs协同控制区,整个长三角区域的O3生成对于NOx排放量更为敏感。管控措施越强,核心区的O3生成对于NOx排放越敏感,且O3浓度与NOx浓度的相关性越强。对NOx和VOCs的协同控制降低排放,是关系O3浓度管控的一项重要工作。

Evaluation of Ozone Change and Control Effects in Yangtze River Delta Region During G20 Submit

In order to study the characteristics of ozone change in Yangtze River Delta during the G20 Summit and assess the impact of the implementation of the control measures on the ozone concentration,the air quality monitoring data,meteorological data and emissions inventory data of Hangzhou and the entire summit area were used to analyze the temporal and spatial distribution characteristics of O3 and NO2 concentrations and meteorological conditions from August 10 thto September 20 th,2016.By comparing the temporal and spatial variation of O3 concentration of different control areas and the differences of emissions in different scenarios,the control effect during G20 summit guarantee period was quantitatively evaluated in different control periods.The obtaining results were as follows: The control measures for primary emission of pollutants and fine particulate matter were effective during the G20 summit. The ozone concentration in the core area was higher than that of the strictly controlled areas and controlled areas,higher than 11. 2 and 9. 2 μg/m^3 respectively. Nitrogen oxide (NOx ) control during the daytime caused the daily variation of ozone to increase by nearly 50 μg/m^3. The minimum O3 concentration in the core area was significantly higher than that of the surrounding areas. During the summit guarantee period,satellite data and site observations showed that the core area was converted from the VOCs control region to the NOx -VOCs coordinated control region. Ozone generation in the entire Yangtze River Delta region was more sensitive to the NOx emissions. The stronger control measures taken,the more sensitive ozone generation in the core area was to the NOx emissions,as well as the stronger correlation between O3 and NOx was. The coordinated control measures to reduce emissions of NOx and VOCs are important tasks related to the control of ozone concentration. The experience of air quality assurance of the summit has important scientific significance and practical value for future work.