武汉市2014—2017年大气污染物分布特征及其潜在来源分析  

Variation characteristics and potential sources of air pollutants during 2014—2017 in Wuhan

作　　者：高正旭[1] 王晓玲[2] 向华[1] 苟阿宁[2] GAO Zhengxu;WANG Xiaoling;XIANG Hua;GOU Aning(Wuhan Regional Climate Centre,Wuhan 430074;Wuhan Central Meteorological Office,Wuhan 430074)

机构地区：[1]武汉区域气候中心,武汉430074 [2]武汉中心气象台,武汉430074

出　　处：《环境科学学报》2018年第11期4440-4453,共14页Acta Scientiae Circumstantiae

基　　金：国家重点研发计划(No.2017YFC0212603);中国气象局气象关键技术集成与应用项目(No.CAMGJ2014M35);国家自然科学基金(No.91644224)~~

摘　　要：利用武汉市2014—2017年大气污染物(SO_2、NO_2、CO、O_3、PM_(2.5)和PM_(10))和气象要素的观测数据,分析了大气污染物的变化特征及其影响因素.使用HYSPLIT模式计算了影响武汉市的主要气团类型,并利用潜在源区贡献(PSCF)和浓度权重轨迹(CWT)分析方法,揭示了研究期内武汉市不同大气污染物的潜在源区分布及其贡献特性.结果表明,武汉市2014—2017年空气质量逐年好转,SO_2、O_3、PM_(2.5)和PM_(10)的浓度呈逐年下降的趋势,但NO_2和CO的浓度先下降后上升.2017年SO_2、O_3、PM_(2.5)、PM_(10)、NO_2和CO的浓度分别为9.6、50.8、52.7、89.2、47.5μg·m^(-3)和1.1 mg·m^(-3),分别比2014年降低了64.3%、23.0%、24.7%、18.8%、3.5%和5.9%.大气污染物存在显著的季节变化和月变化.大气污染物在四个季节中日变化类似,SO_2和O_3均为单峰型分布,NO_2、CO、PM_(2.5)和PM_(10)均为双峰型分布.武汉市空气污染以PM_(2.5)为主,随着污染程度的加剧PM_(2.5)/PM_(10)的值逐渐增大,在空气质量为严重污染时,PM_(2.5)/PM_(10)高达90%,比空气质量为优时高了31.34%.局地气团(45%)和来自山西、陕西和河南一带的西北气团(12.1%)下大气污染物浓度较高.大气污染物的潜在源区贡献(WPSCF)和浓度权重轨迹(WCWT)的较大值主要集中在武汉市本地及其周边地区,局地污染对武汉市大气污染物的贡献较大,但不同大气污染物受到排放源分布和停留时间等影响其WPSCF和WCWT的分布范围不同.Air pollutants （SO2, NO2, CO, O3, PM2.5 and PM10 ） and meteorological elements during 2014--2017 in Wuhan were used together to analyze the air pollutants＇ variation feature and their influencing factors. The major types of air masses influencing Wuhan were derived by using the Hybrid Single-Particle Lagrangian Integrated Trajectory （HYSPLIT） modeling system. Additionally, the distributions of potential source region and their contribution fractions for different air pollutants were derived by using the methods of the potential source contribution function （ PSCF ） and the concentration weighted trajectory （CWT）. Results show that the air quality improved from 2014 to 2017, the concentrations of SO2, O3, PM2.5, and PMlo show an overall decrease gradually while the NO2 and CO show a short decrease then followed by an increase from 2014 to 2017. The annual concentrations of S02, 03, PM2.5, PMI0, NO2, and CO were 9.6, 50.8, 52.7, 89.2, 47.5 μg·m-3, and 1.1 mg·m-3 in 2017, which dropped by 35.7%, 77.0%, 75.3%, 81.2%, 96.5% and 94.1% compared with those in 2014, respectively. The air pollutants exhibited significant seasonal and monthly variations. The diurnal variations of air pollutants were similar in four seasons, with unimodal distributions for SOz and 03 and bimodal distributions for NO2, CO, PM2.5 and PM10. The air pollution in Wuhan was still dominated by fine particulate matter. The ratio of PM2.5/PMI0 enhanced with the deterioration of air quality and can reach as high as 0.9 when the air quality status was seriously polluted （ air quality index （AQI） 〉300）, which increased by 31.34% compared with the ratio when the air quality was excellent （0〈AQI〈 50）. Air pollutants, which were influenced by local air masses （ 45% ） and northwestern air masses （ 12.1% ） originated from Shanxi, Shanxi and Henan, had relatively high concentrations. High values of the pollutant WPSCF （weighted potential source contribution function） and WCWT （weighted concentration-weighte

关 键 词：武汉 大气污染物 年变化 日变化 潜在源区 

分 类 号：X51[环境科学与工程—环境工程]