| 长三角冬季一次霾过程气溶胶及其水溶性离子的区域分布特征 |
| 摘要点击 3037 全文点击 1452 投稿时间：2014-11-23 修订日期：2015-03-12 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 长江三角洲地区 霾 天气形势 水溶性离子 谱分布 |
| 英文关键词 Yangtze River Delta haze meteorological situation water-soluble-ions size distribution |
| 作者 | 单位 | E-mail | | 王曼婷 | 南京信息工程大学中国气象局气溶胶-云-降水重点开放实验室, 南京 210044
南京信息工程大学气象灾害预报预警与评估协同创新中心, 南京 210044 | 13813008703@163.com | | 朱彬 | 南京信息工程大学中国气象局气溶胶-云-降水重点开放实验室, 南京 210044
南京信息工程大学气象灾害预报预警与评估协同创新中心, 南京 210044 | binzhu@nuist.edu.cn | | 王红磊 | 南京信息工程大学中国气象局气溶胶-云-降水重点开放实验室, 南京 210044
南京信息工程大学气象灾害预报预警与评估协同创新中心, 南京 210044 | | | 薛国强 | 南京信息工程大学中国气象局气溶胶-云-降水重点开放实验室, 南京 210044
南京信息工程大学气象灾害预报预警与评估协同创新中心, 南京 210044 | | | 何俊 | 宁波诺丁汉大学化学与环境工程系, 宁波 315100 | | | 徐宏辉 | 浙江省气象科学研究所, 杭州 310008 | | | 曹锦飞 | 苏州市气象局, 苏州 215000 | |
|
| 中文摘要 |
| 为研究长江三角洲地区霾天水溶性离子的区域污染特征,于2013年1月18~24日使用Andersen气溶胶粒度分布采样器和离子色谱仪(850professional IC)对南京、苏州、杭州、宁波这4个城市和临安区域大气本底站的大气气溶胶质量浓度及水溶性离子进行了同期观测分析,并结合天气形势分析了长三角地区大范围霾天气的形成原因及水溶性离子的分布特征.结果表明,观测期间长三角处于高压以及高压前部,气压梯度较大时,低层大气有明显气流辐散,有利于污染物扩散; 处于弱低压及弱高压的均压场形势下,并伴随有大气低层气流辐合现象时不利于污染物扩散.观测期间霾天气发展过程中,各监测点的大气颗粒物及其中水溶性离子(TWSS)增加显著; TWSS增加比例分别为杭州0.9%、临安4.2%、南京8.1%.二次离子SO42-、NO3-、NH4+均为细模态(粒径<2.1 μm)分布,峰值有一个从0.43~0.65 μm向0.65~1.1 μm段迁移的过程,Ca2+、Mg2+在4.7~5.8 μm出现峰值,Na+、Cl -、K+则呈双模态分布.各监测点TWSS中的二次无机离子SNA( NH4+、SO42-和NO3-)浓度上升较快,上升百分比分别为杭州3%、临安55%、南京64.9%; SO42-在SNA中所占比例最大,可达45%; 各监测点NO3-/SO42-的比值均大于固定源NO3-/SO42-(0.5)比值,可能说明流动源在区域污染过程中对颗粒物的贡献相对较大. |
| 英文摘要 |
| To investigate the pollution characteristics of water soluble ions in fine atmospheric particles in Yangtze River Delta during the haze period from 18th to 24th Jan 2013, a joint sampling campaign using Andersen sampler was conducted at five cities (including Nanjing, Suzhou, Hangzhou, Lin'an and Ningbo). The analysis of size distribution of these ionic species coupled with the local meteorological conditions may shed some insightful light on the haze formation mechanism in this region. The result has shown: firstly, during the observation period, when Yangtze River Delta located at high pressure or in the front of high pressure, and has a large pressure gradient, the lower atmosphere has a significant airflow divergence in favor of pollutant dispersion; while located in weak low pressure and weak high pressure, the equalizing pressure field is not favorable for pollutant dispersion, especially accompanied with lower atmosphere convergence airflow. Secondly, during the hazy period, the concentration of fine particles and total water-soluble inorganic ions (TWSS) has increased dramatically; the increasing proportions of TWSS in fine particles are: Hangzhou 0.9%, Lin'an 4.2%, Nanjing 8.1%. The particle size of secondary ions of SO42-, NO3-, NH4+ complies fine mode(particle size<2.1 μm), whose peaks migrates from 0.43-0.65 μm to 0.65-1.1 μm during the observation period, the peak of particle size of Ca2+, Mg2+ appears at 4.7-5.8 μm, while the ions of Na+, Cl-, K+ show a bimodal distribution. Moreover, secondary inorganic ions play a significant role in the formation of haze pollution, where the concentrations of secondary inorganic ions of NH4+, SO42- and NO3- have higher increasing rates; their relative proportions of increasing from each monitoring points are: Hangzhou 3%, Lin'an 55% and Nanjing 64.9%. Finally, SO42- has the highest mass contribution to SNA, up to 45%; also, the NO3-/SO42- ratios in each monitoring points are always higher than a fair 0.5, which could indicate the significant contribution of mobile source towards this particle pollution. |
|
|
|
