摘要
气温不仅影响大气污染物排放,同时还影响着大气扩散能力。文章利用哈尔滨、乌鲁木齐、北京、兰州、成都、南京和广州7座城市2000-2013年API资料、2013-2018年AQI资料以及同期地面常规气象观测资料和探空资料,通过拟合2016之前上述7城市各自日均气温与API、AQI及5种污染物(PM2.5、PM10、SO2、NO2和CO)浓度间的关系,探寻不同城市的大气重污染对应的温度阈值及其分布特征,并用2017-2018年的AQI资料检验该温度阈值对大气重污染事件的捕获能力。研究结果表明:就同一城市而言,存在一个使API、AQI和5种污染物浓度均达到最大的气温临界值,由此提出了大气重污染风险温度阈值(THP)的概念,哈尔滨、乌鲁木齐、北京、兰州、成都、南京和广州7座城市的THP依次为-15.8、-12.4、-1.5、-3.4、8.0、6.8和17.1℃。同时还发现当气温位于THP及其附近时,对应当地多为静稳天气(混合层厚度和通风系数均最小),呈现出最不利于大气污染物扩散的气象条件,进而易造成大气重污染甚至是污染事件的发生。由此可见,THP是边界层大气静稳特征的一个缩影,能较好地反映大气重污染潜势,7座城市THP捕获重污染事件的百分比整体在50%以上。该研究为上述7座城市的大气污染潜势预报及污染防控探寻了一个新的更简洁明了的重要污染气象参数,也为其它城市开展类似研究提供了借鉴参考。
Temperature not only affects the emission of atmospheric pollution,but also affects the ability of atmospheric diffusion.In this study,the API data from 2000 to 2013,AQI data from 2013 to 2018,meteorological data and sounding data from 2000 to 2018 of 7 cities(including Harbin,Beijing,Nanjing,Guangzhou,Chengdu,Lanzhou and Urumqi)were used,respectively,to explore temperature threshold with heavy air pollution in different cities,the relationship between ambient temperature and two indices(API and AQI)were fitted as well as temperature and five pollutants(PM2.5,PM10,SO2,NO2 and CO)concentration,using all API data and AQI data during 2013 to 2016,respectively.In addition,AQI data during 2017 to 2018 was used to verify.The results showed that there was a temperature threshold,at which the value of pollution indices and pollutants all reach their maximum.Hence,the concept of temperature threshold for risk of heavy pollution(THP)was put forward.The THP of Harbin,Urumqi,Beijing,Lanzhou,Chengdu,Nanjing and Guangzhou were -15.8℃,-12.4℃,-1.5℃,-3.4℃,8.0℃,6.8℃,and 17.1℃,respectively.The study further suggested that it is mostly stationary weather with the thickness of mixed layer and the minimum ventilation coefficient when temperature is near around the THP.THP indicated the most disadvantageous meteorological conditions for the diffusion of atmospheric pollutants,which can easily lead to heavy air pollution and even pollution events.In addition,it was found THP can capture more than 50% heavy pollution events during test period.Hence,TIP is intrinsically associated with the atmospheric structure and static stability in the planetary boundary layer,especially during stagnant weather.It therefore provides a simple measure of air pollution potential,and can be used to quantify the potential air pollution severity for a given pollution emission level.Being an easy-to-obtain and simple-touse meteorological parameter,TIP can be used for air pollution potential assessment and prediction,as well as pollution prevention and control applications for the seven cities.Furthermore,it could provide reference for other cities to carry out similar researches.
作者
张莹
贾旭伟
刘卫平
张婕
王式功
张小玲
曹佳阳
ZHANG Ying;JIA Xuwei;LIU Weiping;ZHANG Jie;WANG Shigong;ZHANG Xiaoling;CAO Jiayang(Institute of Environmental Meteorology and Health/Plateau Atmosphere and Environment Key Laboratory of Sichuan Province,School of Atmospheric Science,Chengdu University of Information Technology,Chengdu 610225,China;Chinese People's Liberation Army 94498,Nanyang 072655,China;Lanzhou Regional Climate Center,Lanzhou 730020,China)
出处
《环境科学与技术》
CAS
CSCD
北大核心
2019年第10期1-8,共8页
Environmental Science & Technology
基金
四川省重大科技专项（2018SZDZXX23）
国家自然科学基金（91644226）
国家重点研发计划（2016YFA0602004）
成都信息工程大学科研启动金（KYTZ201723）
四川省教育厅科研项目（2018Z114）
关键词
大气重污染风险温度阈值
静稳特征
污染潜势
temperature threshold for risks of heavy air pollution
static stability
air pollution potential
