Wang Zhen-Bin, Liu An-Kang, Lu Wen, Yang Xiao-Min, Wang Hong-Lei, Chen Kui, Xia Li
Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science & Technology, Nanjing 210044, China.
State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
Huan Jing Ke Xue. 2019 Dec 8;40(12):5213-5223. doi: 10.13227/j.hjkx.201906052.
To explore the variation in characteristics of atmospheric pollutants at different stages of haze, the monitor for aerosols and gases in ambient air (MARGA) was used to observe the concentrations of precursor pollutants (NH, HNO, and SO) and eight water-soluble ions in a regional haze in the Yangtze River Delta region from November 18 to December 07, 2018. Combined with environmental data (PM, NO, CO, and O) and meteorological data, the causes of regional haze formation, diurnal variation characteristics of air pollutants, and distribution characteristics of air pollutants in different stages of haze were analyzed. The results showed that the Yangtze River Delta region was mainly controlled by a ridge of high pressure during the haze process and the weather situation was stable, which was conducive to the accumulation of air pollutants. On hazy days, the concentrations of PM, NO, NO, SO, NH, Cl, and Na were (118.91±39.23), (61.62±26.34), (45.64±16.01), (18.80±8.02), (20.82±7.16), (3.02±2.25), and (0.23±0.22) μg·m, respectively, and these were 2.73, 1.63, 2.64, 1.94, 2.50, 2.05, and 2.56 times the levels found on clean days, respectively. The concentration of CO was (1.34±0.39) mg·m on hazy days, which was 1.86 times that found on clean days. Diurnal variation characteristics of different air pollutants were different, as were the distribution characteristics of air pollutants at different haze stages. The concentrations of SO was the highest in the haze occurrence stage. The concentrations of PM, NO, NH, CO, and SNA were highest in the haze development stage, and the concentrations of O, Cl, Na, and K were highest in the haze dissipation stage. The relative contributions of SNA to PM in different stages of haze could reach 94%-96%, and their growth rate was largest in the development stage. The order of growth rate was NO > NH > SO. SNA mainly existed in the form of NHNO on clean days and in the occurrence and development stages, and (NH)SO in the dissipation stage. This haze process was mainly caused by the growth of NO, which was mainly generated by gas-phase homogeneous phase reaction, and NOcontributes 51.06%, 51.85%, and 48.22%, respectively, to PM in the occurrence, development, and dissipation stages of haze.
为探究雾霾不同阶段大气污染物特征的变化，于2018年11月18日至12月7日，利用大气环境气态和颗粒态污染物监测仪（MARGA）对长江三角洲地区一次区域雾霾过程中的前体污染物（NH₃、HNO₃和SO₂）及8种水溶性离子浓度进行观测。结合环境数据（PM₂.₅、NO₂、CO和O₃）及气象数据，分析区域雾霾形成原因、空气污染物的日变化特征以及雾霾不同阶段空气污染物的分布特征。结果表明，雾霾过程中长江三角洲地区主要受高压脊控制，天气形势稳定，利于空气污染物积累。雾霾天PM₂.₅、NO₂、NOₓ、SO₂、NH₃、Cl⁻和Na⁺浓度分别为（118.91±39.23）、（61.62±26.34）、（45.64±16.01）、（18.80±8.02）、（20.82±7.16）、（3.02±2.25）和（0.23±0.22）μg·m⁻³，分别是清洁天的2.73、1.63、2.64、1.94、2.50、2.05和2.56倍。雾霾天CO浓度为（1.34±0.39）mg·m⁻³，是清洁天的1.86倍。不同空气污染物的日变化特征不同，雾霾不同阶段空气污染物的分布特征也不同。SO₂浓度在雾霾发生阶段最高。PM₂.₅、NO₂、NH₃、CO和SNA（可溶性无机离子）浓度在雾霾发展阶段最高，O₃、Cl⁻、Na⁺和K⁺浓度在雾霾消散阶段最高。SNA在雾霾不同阶段对PM₂.₅的相对贡献可达94% - 96%，且在发展阶段增长率最大。增长率顺序为NOₓ > NH₃ > SO₂。清洁天及雾霾发生和发展阶段SNA主要以NH₄NO₃形式存在，消散阶段以（NH₄）₂SO₄形式存在。此次雾霾过程主要由NOₓ增长导致，其主要由气相均相反应生成，在雾霾发生、发展和消散阶段对PM₂.₅的贡献率分别为51.06%、51.85%和48.22%。
