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Characteristics of Aerosol Ionic Compositions in Summer 2003 at Lin''''an of Yangtze Delta Region 总被引：1，自引：0，他引：1 
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下载免费PDF全文 YAN Peng ZHANG Yangmei YANG Dongzhen TANG Jie ZHOU Xiuji 《Acta Meteorologica Sinica》2006,20(3):374-382
With the size-resolved aerosol mass and ion composition data obtained at Lin'an regional atmospheric pollution monitoring station in July 2003, the size distributions of aerosol mass and ionic components, and the correlations between major ion pairs were analyzed. The primary results indicate that in the period of in-situ measurement, the aerosols are mainly composed of fine particles. The mass of aerosols with size less than 2.1μm accounts for 66% of the total mass of all size ranges, in which about 50% of the mass is contributed by the particles with size less than 0.65μm. Similar to the size distributions of aerosol mass, the water-soluble ions are mainly concentrated in the size range of <0.65μm, accounting for about 77% of the sum of analyzed ions, and the ions within the range of <2.1μm reach 88%. The sulfate, ammonium, and potassium are the dominant ionic components in fine particles (particle size less than 2.1μm). Ion correlation analysis suggests that the sulfates in fine particles are mostly in the compounds of (NH4)2SO4, Na2SO4, and K2SO4, but for submicron particles the sulfates are mainly in the form of (NH4)2SO4. 相似文献
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分别利用碳成分分析仪、离子色谱仪和原子吸收光谱仪等获取浙江省临安地区大气气溶胶在春、夏、秋、冬四季的质量浓度、离子与碳成分特性，并对不同粒径气溶胶成分分布特点作了较详细分析。结果表明:气溶胶质量浓度、可溶性离子浓度以及碳成分浓度具有明显的季节变化趋势。整个尺度范围内，气溶胶质量浓度季节变化特点为春季浓度最高，达到534 μg/m3；冬季次之，质量浓度为117.21 μg/m3；夏季浓度最低，平均为65.7 μg/m3；秋季质量浓度98.6 μg/m3。可溶性离子成分在气溶胶中所占比例具有明显的季节性，其中夏季最高为49.4%，春季最低为11.3%。硫酸根离子SO42-和氨根离子NH4+和硝酸根离子NO3- 3种离子浓度之和约占离子总量的75%~83%。受温度影响，硝酸根离子NO3-浓度随季节变化幅度较大，夏季平均浓度为1.7 μg/m3, 冬季平均浓度为11.5 μg/m3，是夏季浓度的6.8倍。碳浓度分布特点显示，气溶胶中元素碳浓度春季最高，夏季最低。有机碳浓度春季最高，冬季最低。气溶胶粒度分布特点也非常明显。四季中粒径小于11 μm（PM11）的气溶胶均占气溶胶总量的90%以上，粒径小于2.1 μm（PM2.1）的气溶胶占到气溶胶总量的53%以上。可溶性离子在粒径小于2.1 μm气溶胶颗粒中，以硫酸根离子、氨根离子和硝酸根离子为主。碳成分尺度分布特征为颗粒越小，有机碳及元素碳浓度越高。 相似文献
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利用2009年11—12月在天津武清气象局测量的云凝结核(CCN:Cloud Condensation Nuclei)浓度资料以及气溶胶数谱分布的观测资料,分析了武清地区在不同过饱和度(0.1%～1.0%)下云凝结核浓度及活化率的变化特征。结果表明:武清地区冬季CCN数浓度变化范围很大,过饱和度1%时,浓度变化范围为4000～32000cm-3,且浓度受风速影响明显,风速2级以下CCN数浓度很高,过饱和度1%时,其平均浓度可达16000cm-3,但对于4级风速以上CCN平均浓度为4000cm-3左右;在过饱和度0.1%～0.4%间CCN浓度变化较大,过饱和度每增加0.1%,CCN浓度增加值平均约为过饱和度0.4%～1.0%间浓度增量的5倍。低过饱和度(0.1%、0.2%)下,活化率受风速影响明显,1级风速下的CCN活化率约为4级风速下的3倍,但在过饱和度1%时活化率则相差不大。CCN浓度的日变化呈双峰型,峰值时刻为北京时间08:00和18:00左右,活化率的日变化则呈双谷型,这主要是受局地排放影响的结果。利用指数函数拟合各风速下CCN浓度过饱和度谱,表明该地谱型为典型的大陆型。 相似文献
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Xuefei?Qi Junying?SunEmail author Lu?Zhang Xiaojing?Shen Xiaoye?Zhang Yangmei?Zhang Yaqiang?Wang Haochi?Che Zhouxiang?Zhang Junting?Zhong Kaiyan?Tan Huarong?Zhao Sanxue?Ren 《Acta Meteorologica Sinica》2018,32(1):38-48
A humidification system was deployed to measure aerosol hygroscopicity at a rural site of the North China Plain during the haze red-alert period 17–22 December 2016. The aerosol scattering coefficients under dry [relative humidity (RH) < 30%] and wet (RH in the range of 40%–85%) conditions were simultaneously measured at wavelengths of 450, 550, and 700 nm. It is found that the aerosol scattering coefficient and backscattering coefficient increased by only 29% and 10%, respectively when RH went up from 40% to 80%, while the hemispheric backscatter fraction went down by 14%, implying that the aerosol hygroscopicity represented by the aerosol scattering enhancement factor f(RH) is relatively low and RH exerted little effects on the aerosol light scattering in this case. The scattering enhancement factors do not show significant differences at the three wavelengths, only with an approximate 2% variation, suggesting that the aerosol hygroscopicity is independent of the wavelength. Aerosol hygroscopicity is highly dependent on the aerosol chemical composition. When there is a large mass fraction of inorganics and a small mass fraction of organic matter, f(RH) reaches a high value. The fraction of NO3– was strongly correlated with the aerosol scattering coefficient at RH = 80%, which suggests that NO3– played an important role in aerosol hygroscopic growth during the heavy pollution period. 相似文献
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Yangmei ZHANG Yaqiang WANG Xiaoye ZHANG Xiaojing SHEN Junying SUN Lingyan WU Zhouxiang ZHANG Haochi CHE 《Journal of Meteorological Research》2018,(1)
Air pollution is a current global concern. The heavy air pollution episodes(HPEs) in Beijing in December 2016 severely influenced visibility and public health. This study aims to survey the chemical compositions, sources, and formation processes of the HPEs. An aerodyne quadruple aerosol mass spectrometer(Q-AMS) was utilized to measure the non-refractory PM1(NR-PM1) mass concentration and size distributions of the main chemical components including organics, sulfate, nitrate, ammonium, and chloride in situ during 15–23 December 2016. The NR-PM1 mass concentration was found to increase from 6 to 188 μg m–3 within 5 days. During the most serious polluted episode, the PM1 mass concentration was about 2.6 times that during the first pollution stage and even 40 times that of the clean days. The formation rates of PM2.5 in the five pollution stages were 26, 22, 22, 32, and 67 μg m~(–3) h–1, respectively. Organics and nitrate occupied the largest proportion in the polluted episodes, whereas organics and sulfate dominated the submicron aerosol during the clean days. The size distribution of organics is always broader than those of other species, especially in the clean episodes. The peak sizes of the interested species grew gradually during different HPEs. Aqueous reaction might be important in forming sulfate and chloride, and nitrate was formed via oxidization and condensation processes. PMF(positive matrix factorization) analysis on AMS mass spectra was employed to separate the organics into different subtypes. Two types of secondary organic aerosol with different degrees of oxidation consisted of 43% of total organics. By contrast, primary organics from cooking, coal combustion, and traffic emissions comprised 57% of the organic aerosols during the HPEs. 相似文献
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Junting Zhong Xiaoye Zhang Yaqiang Wang Junying Sun Yangmei Zhang Jizhi Wang Kaiyan Tan Xiaojing Shen Haochi Che Lu Zhang Zhouxiang Zhang Xuefei Qi Huarong Zhao Sanxue Ren Yang Li 《Acta Meteorologica Sinica》2017,31(5):809-819
Based on observations of urban mass concentration of fine particulate matter smaller than 2.5 μm in diameter (PM2.5), ground meteorological data, vertical measurements of winds, temperature, and relative humidity (RH), and ECMWF reanalysis data, the major changes in the vertical structures of meteorological factors in the boundary layer (BL) during the heavy aerosol pollution episodes (HPEs) that occurred in winter 2016 in the urban Beijing area were analyzed. The HPEs are divided into two stages: the transport of pollutants under prevailing southerly winds, known as the transport stage (TS), and the PM2.5 explosive growth and pollution accumulation period characterized by a temperature inversion with low winds and high RH in the lower BL, known as the cumulative stage (CS). During the TS, a surface high lies south of Beijing, and pollutants are transported northwards. During the CS, a stable BL forms and is characterized by weak winds, temperature inversion, and moisture accumulation. Stable atmospheric stratification featured with light/calm winds and accumulated moisture (RH > 80%) below 250 m at the beginning of the CS is closely associated with the inversion, which is strengthened by the considerable decrease in near-surface air temperature due to the interaction between aerosols and radiation after the aerosol pollution occurs. A significant increase in the PLAM (Parameter Linking Aerosol Pollution and Meteorological Elements) index is found, which is linearly related to PM mass change. During the first 10 h of the CS, the more stable BL contributes approximately 84% of the explosive growth of PM2.5 mass. Additional accumulated near-surface moisture caused by the ground temperature decrease, weak turbulent diffusion, low BL height, and inhibited vertical mixing of water vapor is conducive to the secondary aerosol formation through chemical reactions, including liquid phase and heterogeneous reactions, which further increases the PM2.5 concentration levels. The contribution of these reaction mechanisms to the explosive growth of PM2.5 mass during the early CS and subsequent pollution accumulation requires further investigation. 相似文献
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黑碳气溶胶是环境大气中浓度较低的一种气溶胶粒子组分,因其对光的吸收作用,及其对空气质量和人体健康的影响,而成为当前国际气候变化和环境研究中关注的热点问题之一。本文围绕黑碳的减排问题,介绍黑碳的来源、全球分布,讨论全球温室气体减排和区域空气质量控制对黑碳减排的影响,综述控制和改善燃烧条件、减少开放式生物质燃烧和黑碳封存等减排黑碳的措施。文章还分析了黑碳未能成为全球减排共识的原因,并对中国有关黑碳减排的政策选择提出了建议。 相似文献
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