2015年12月气流轨迹对长三角区域细颗粒物浓度和分布的影响

发布时间：2018-02-27 14:21

本文关键词： PM. 后向轨迹聚类分析潜在源贡献因子法浓度权重轨迹长三角区域　出处：《环境科学学报》2016年12期 　论文类型：期刊论文

【摘要】：2015年12月中国长三角区域经历了4次高浓度、大范围、长时间的颗粒物污染.本研究基于HYSPLIT后向轨迹模式结合GDAS(Global Data Assimilation System,全球资料同化系统)气象数据和长三角区域15个主要城市的PM_(2.5)质量浓度数据,利用轨迹聚类、潜在源贡献因子法(Potential Source Contribution Function,PSCF)和浓度权重轨迹法(Concentration-Weighted Trajectory,CWT)分析了2015年12月长三角区域主要气流轨迹方向和重污染过程中细颗粒物的潜在来源分布,探讨了不同污染过程的气象特征和影响气团分布.结果表明,2015年12月长三角区域主要受到来自西北和北方气流影响(B、C、D类),其出现概率分别为39.5%、20.0%和25.8%;西方内陆(A类)出现概率最低,仅为14.7%.西北内陆方向长距离输送(B类)对长三角区域空气质量影响较大,在此类气团主导下,长三角区域颗粒物(PM_(2.5)、PM_(10))质量浓度和气态污染物(SO_2、NO_2、CO)质量浓度平均值分别为90.9、135.1、32.4、54.4和1200μg·m~(-3),且粗颗粒物比重较其它3类聚类高;经过东北海面气团(C类)携带的颗粒物浓度也较高,且PM_(2.5)/PM_(10)比值最高,可能是其水汽含量较高加剧了污染物的二次生成.PSCF和CWT分析结果表明,污染过程1(12月5—8日)期间,长三角区域PM_(2.5)浓度主要受内蒙东部、京津冀、山东和江苏东部等地影响;污染过程2(12月10—11日)和污染过程3(12月13—15日)期间,京津冀地区对长三角区域PM_(2.5)浓度的贡献都较低,污染过程2的主要潜在源区较为集中,主要为内蒙东部、辽宁、山东东部、江苏和上海;而污染过程3的潜在源区较广,内蒙西南地区、甘肃、山西、陕西、河南、河北南部、山东、安徽北部等地及长三角本地对区域PM_(2.5)浓度均有重要贡献;污染过程4(12月20—27日)持续时间最长,相较前3次污染过程,京津冀地区和西南地区对长三角区域PM_(2.5)浓度的贡献相对增加.总体来说,2015年12月4次污染过程期间长三角区域PM_(2.5)污染的潜在贡献源主要集中在华北和华东(长三角)地区,区域性污染和长距离输送对冬季长三角区域空气质量有重要影响.
[Abstract]:In December 2015, the Yangtze River Delta region of China experienced four high concentrations and a wide range. Based on HYSPLIT backward trajectory model combined with GDAS(Global Data Assimilation system (GDAS(Global data assimilation system) meteorological data and mass concentration data of 15 major cities in Yangtze River Delta region, trajectory clustering was used in this study. Potential Source Contribution function (PSCFF) and Concentration-Weighted Trajector (CWTs) were used to analyze the direction of the main airflow trajectory and the distribution of potential sources of fine particulate matter in the heavy pollution process in the Yangtze River Delta region in December 2015. The meteorological characteristics of different pollution processes and the influence of air mass distribution are discussed. The results show that in December 2015, the Yangtze River Delta region was mainly affected by the northwestern and northern air currents, and its occurrence probability was 39.5% and 25.8% respectively. ) the lowest probability of occurrence, The air quality in the Yangtze River Delta region is greatly affected by the long distance transportation type B in the northwestern inland direction, which is dominated by this kind of air mass. In the Yangtze River Delta region, the average mass concentrations of particulate matter and gaseous pollutant so _ 2N _ 2C _ (C) were 90.9 ~ 135.1 ~ 32.4 渭 g 路m ~ (-1) and 1200 渭 g 路m ~ (-3), respectively, and the density of coarse particles was higher than that of the other three clusters, and the concentration of particulate matter passing through the northeast sea air mass was also higher than that of the other three clusters. Moreover, the highest ratio of PMSCF / PSCF / PSCF and CWT showed that the concentration of PMS2.5 in the Yangtze River Delta region was mainly attributed to the eastern part of Inner Mongolia and the Beijing-Tianjin-Hebei region during the pollution process 1 (December, 5-8). During the period of 2 (10-11 December) and 3 (13-15 December) of pollution process, the contribution of Beijing-Tianjin-Hebei region to PM2.5 concentration in Yangtze River Delta region was relatively low, and the main potential sources of pollution process 2 were concentrated. Mainly eastern Inner Mongolia, Liaoning, eastern Shandong, Jiangsu and Shanghai, while the potential source of pollution process 3 is relatively wide, southwest of Inner Mongolia, Gansu, Shanxi, Shaanxi, Henan, southern Hebei, Shandong, Shandong, Both northern Anhui and the Yangtze River Delta make important contributions to the concentration of PMSP 2.5. The pollution process of 4 (20-27 December) lasted the longest, compared with the previous three pollution processes. The contribution of Beijing-Tianjin-Hebei region and southwestern region to the concentration of PMMA-2.5) in the Yangtze River Delta region is relatively increased. In general, the potential sources of contribution to the pollution in the Yangtze River Delta region during the pollution process in December 4th 2015 are mainly concentrated in North China and East China (Yangtze River Delta). Regional pollution and long distance transport have important influence on air quality in Yangtze River Delta region in winter.
【作者单位】：国家环境保护城市大气复合污染成因与防治重点实验室;上海市环境科学研究院;
【基金】：环境保护公益性行业科研专项(No.201409008) 上海市科委科技攻关项目(No.14DZ1202905)~~
【分类号】：X513

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