冷高压影响下高层水平输送对珠海市三维臭氧浓度分布的影响分析  

Effects of high-level horizontal transportation on the three-dimensional ozone concentration distribution over Zhuhai City under cold high pressure

作　　者：刘晨曦 何成 何国文 贺沅平 刘南希 苗圣杰 许欣祺 范绍佳 LIU Chenxi;HE Cheng;HE Guowen;HE Yuanping;LIU Nanxi;MIAO Shengjie;XU Xinqi;FAN Shaojia(School of Atmospheric Sciences,Sun Yat-Sen University,Zhuhai 519082;Guangdong Provincial Observation and Research Station for Climate Environment and Air Quality Change in the Pearl River Estuary,Guangzhou 510275)

机构地区：[1]中山大学大气科学学院,珠海519082 [2]广东省环珠江口气候环境与空气质量变化野外科学观测研究站,广州510275

出　　处：《环境科学学报》2023年第1期119-127,共9页Acta Scientiae Circumstantiae

基　　金：广东省科技计划项目(科技创新平台类)(No.2019B121201002);广东省重点领域研发计划项目(No.2020B1111360003);广东省基础与应用基础研究重大项目(No.2020B0301030004)。

摘　　要：采用地基激光雷达系统测量了近地层臭氧、气溶胶消光系数和风场的垂直分布,研究了2021年11月一次典型臭氧污染过程的时空分布特征.11月16日—17日,在弱冷高压脊天气型下,以下沉气流为主,天气晴好,有利于臭氧生成,在下沉气流主导下,高层气团输送对污染物的分布起决定性作用.其中700 m高度以上气团来源是影响16日与17日臭氧浓度峰值出现时间的重要因子,当该高度气团来自洁净海面时,造成珠海臭氧污染的主要是低层深圳输送的臭氧,臭氧往往停留在珠江口,由夜间海风输送到珠海,污染发生的时间在傍晚,持续到夜间消散;而当该高度气团与低层一样来自于深圳、东莞时,各个高度的气团均携带上游城市生成的污染物,可在下沉气流的作用下直接达到地面,造成污染,污染发生的时间在午后,在本研究中由于下沉气流加强,进一步加强了海陆风,从而使臭氧在17日傍晚得到很好的清除.In this study,a ground-based lidar system was used to measure the vertical distributions of near-surface ozone concentration,aerosol extinction coefficient and wind velocity,which aimed to investigate the spatiotemporal distribution characteristics of a typical ozone pollution process occurred in November,2021.From November 16 to 17,surface pressure field was controlled by the weak cold high-pressure ridge,and the vertical airflow was dominated by downdraught,and the weather was warm and sunny,which were favorable for the generation of ozone.Under the prevailing downdraught,the transport of upper air mass played a key role in the distributions of pollutants near the surface.The source of the air mass above 700 m affected the peak time of ozone concentration on November 16 and 17.When the air mass above 700 m originated from the clean sea surface,the ozone pollution in Zhuhai was mainly caused by the low-level ozone transportation from Shenzhen,and the ozone was accumulated in the Pearl River Estuary and then be transported to Zhuhai by the sea breeze at nightfall.When the air mass above 700 m height and the air mass below 700 m height both originated from Shenzhen and Dongguan,the air masses at all heights carried pollutants generated by the upstream cities and the high-level pollutants could reach the ground under downdraught.The ozone pollution occurred in the afternoon.The strengthening of the downdraught could further strengthen the sea-land breeze,so that the ozone was well removed on the evening of November 17.

关 键 词：珠江口 激光雷达 臭氧 水平输送 珠海 

分 类 号：X51[环境科学与工程—环境工程]