不同时间尺度下杭州市O3污染特征及控制因素  

Characteristics and Control Factors of Ozone Pollution at Different Time Scales in Hangzhou City

作　　者：毛敏娟 刘厚通[2] 杜荣光[3] MAO Minjuan;LIU Houtong;DU Rongguang(Zhejiang Institute of Meteorology Science,Hangzhou 310008,China;Department of Applied Physics,School of Mathematics and Physics,Anhui University of Technology,Ma′anshan 243002,China;Hangzhou Meteorological Bureau,Hangzhou 310058,China)

机构地区：[1]浙江省气象科学研究所,浙江杭州310008 [2]安徽工业大学数理学院应用物理系,安徽马鞍山243002 [3]浙江省杭州市气象局,浙江杭州310058

出　　处：《环境科学研究》2019年第11期1844-1851,共8页Research of Environmental Sciences

基　　金：国家自然科学基金面上项目(No.41475134);浙江省公益性社会发展重点项目(No.2014C23004)~~

摘　　要：通过集中整治,我国空气质量已经有了明显改善,但在减排背景下近地面高ρ(O3)仍是当前最复杂的大气环境问题之一.利用2011—2017年(尤其是杭州市G20峰会期间)ρ(O3)、ρ(NO x)、ρ(VOCs)和气象条件观测数据,分析了杭州市G20峰会期间及不同时间尺度下杭州市ρ(O3)的变化特征及其影响因素.结果表明:①杭州市ρ(O3)日变化呈单峰型特征,15:00左右ρ(O3)达最大值(98.55μg/m^3);ρ(O3)周变化存在“周末效应”,周末ρ(O3)明显高于工作日;1 a中4—9月为ρ(O3)高值期,ρ(O3)峰值出现在5月和9月.以2013年为界,将2011—2017年ρ(O3)变化分成下降和上升2个阶段,2011—2013年呈下降趋势,降幅约为15.02μg m 3,2014—2017年呈上升趋势,增幅约为23.25μg/m^3.②减排措施的实施对ρ(O3)存在双重作用,其可通过降低前体物质量浓度抑制O3的生成,又能引起大气污染物质量浓度下降、太阳辐射增强,从而促进O3的生成.当O3前体物质量浓度较低时,在强太阳辐射等气象条件驱动下,近地面仍会呈现高ρ(O3)的现象.③气象条件是驱动ρ(O3)日、月变化的控制因素;相反,前体物质量浓度则是ρ(O3)周、年变化的控制因素,此时VOCs或NO x控制区、“周末效应”等ρ(O3)变化特征开始显现.研究显示,不同时间尺度下杭州市O3污染的控制因素不同.Although the air quality in China has been significantly improved through regulation,high concentration of ground-level ozone is still among the most complicated environmental issues under the background of emission restrictions.The characteristics of ozone pollution at different time scales in Hangzhou City and their control factors were analyzed with measurements of ozone and its precursors as well as meteorological elements from 2011 to 2017,especially during the G20 Summit in Hangzhou City.The results indicated that diurnal variations of ozone concentration exhibited the characteristics of single peak appeared around 15:00 with about 98.55/m^3 concentration.Weekly variations of ozone concentration presented weekend effect while the levels of ozone concentration were evidently higher in weekend than in weekdays.Monthly ozone concentrations from April to September were higher than that in other months and the two peaks appeared in May and September,respectively.Inter-annual variations of ozone concentration from 2011 to 2017 were divided into two stages with 15.02/m^3 decrease before 2013 and 23.25/m^3 increase after 2013,respectively.The emission restrictions showed dual effects on ozone concentration.On the one hand,it restrains ozone generation by reducing the concentration of ozone precursors.On the other hand,it enhances ozone generation by reducing pollutant concentrations and increasing atmospheric radiation.Therefore,even with low ozone precursor concentrations,high concentration of ground-level ozone may still occur by meteorological conditions such as strong atmospheric radiation.Meteorological conditions are the major drivers of the diurnal and monthly changes of ozone concentration;otherwise ozone precursors are the major driver of weekly and inter-annual ozone variations,and then the change characteristics of ozone concentration such as NO x(VOCs)-limited regime and weekend effect may become clearer.Overall,the control factors of ozone concentration at different time scales were different.

关 键 词：杭州市 G20峰会 O3 气象条件 前体物 

分 类 号：X513[环境科学与工程—环境工程]