兰州市冬季气溶胶吸光特性研究——黑碳与棕色碳的区分及特征分析

doi:10.7522/j.issn.1000-0240.2017.0138

摘要/Abstract

摘要： 为研究兰州市冬季亚微米气溶胶的吸光特性，利用2014年1月10日至2月4日黑碳仪（AE31）和高分辨率飞行时间质谱仪（HR-ToF-AMS）观测资料，对气溶胶的吸光特性进行了分析。首先根据黑碳气溶胶（BC）和棕色碳气溶胶（BrC）的光学特性差异对二者进行区分，然后分析两者的吸光特性。结果表明：观测期间亚微米气溶胶中黑碳和有机物的平均浓度分别为3.7 μg·m^-3和29.3 μg·m^-3。随着亚微米气溶胶浓度的增加，黑碳和棕色碳吸收系数均增加，但棕色碳吸收系数增加得更快。黑碳和棕色碳在550 nm处的平均吸收系数分别为（9.9±5.9）Mm^-1和（51.0±28.1）Mm^-1。棕色碳的Angstrom指数为4.4。另外，采用正定矩阵因子解析模型（PMF）将棕色碳的来源划分为六种（碳氢类有机气溶胶（HOA）、烹饪类有机气溶胶（COA）、生物质燃烧（BBOA）、燃煤排放（CCOA）、半挥发低氧化程度有机气溶胶（SV-OOA）和低挥发高氧化程度有机气溶胶（LV-OOA）），并通过多元线性回归方法计算了各来源的吸光贡献，其中BBOA和CCOA对棕色碳吸光系数的贡献为41.5%，其次是SV-OOA（32.8%）、LV-OOA（14.2%）、HOA（7.8%）和COA（3.8%），说明一次和二次有机气溶胶均为兰州地区棕色碳的重要来源。

关键词: 兰州, 黑碳, 棕色碳, 吸收系数, 来源

Abstract: The optical absorption properties and composition of non-refractory submicron aerosol were measured by the combination of aethalomerter and HR-ToF-AMS in Lanzhou, China, from 10th January through 4th February 2014. Black carbon and brown carbon from combustion were segregated by optical method. The average mass concentrations of black carbon and organics in PM₁ were 3.7 μg·m^-3 and 29.3 μg·m^-3, respectively. Visibility decreased exponentially with the increase of BC concentration. BrC absorption coefficient increased faster than those of BC when haze became heavier. During the campaign, the absorption coefficient at 550 nm was (51.0±28.1) Mm^-1 for BC and (9.9±5.9) Mm^-1 for BrC, respectively. The absorption Angstrom exponent of BrC was approximately 4.4. Source apportionment of organic aerosol detected by HR-TOF-AMS was performed by positive matrix factorization (PMF) and six species of OA were identified, including hydrocarbon-like OA (HOA), cooking-emission related OA (COA), biomass burning OA (BBOA), coal combustion OA (CCOA), semi-volatile oxygenated OA (SV-OOA) and low-volatility oxygenated OA (LV-OOA). A multiple linear regression was used to calculate the relative absorption contribution of each species in OA. Thereinto, BBOA and CCOA accounted for 41.5% of the total absorption of BrC, followed by SV-OOA (32.8%), LV-OOA (14.2%), HOA(7.8%) and COA (3.8%), suggesting that POA and SOA might have contributed comparably to BrC absorption coefficient in Lanzhou.

Key words: Lanzhou, black carbon, brown carbon, absorption coefficient, sources

中图分类号:

X831

谢聪慧, 徐建中. 兰州市冬季气溶胶吸光特性研究——黑碳与棕色碳的区分及特征分析[J]. 冰川冻土, 2017, 39(6): 1249-1257.

XIE Conghui, XU Jianzhong. Study on the absorption characteristics of winter aerosol in Lanzhou: the distinction between black carbon and brown carbon and a characteristic analysis[J]. JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY, 2017, 39(6): 1249-1257.

参考文献

[1] Bond T C, Doherty S J, Fahey D W, et al. Bounding the role of black carbon in the climate system:A scientific assessment[J]. Journal of Geophysical Research:Atmospheres, 2013, 118(11):5380-5552.
[2] Laskin A, Laskin J, Nizkorodov S A. Chemistry of atmospheric brown carbon[J]. Chemical Reviews, 2015, 115(10):4335-4382.
[3] Feng Yan, Ramanathan V, Kotamarthi V R. Brown carbon:a significant atmospheric absorber of solar radiation?[J]. Atmospheric Chemistry and Physics, 2013, 13(17):8607-8621.
[4] Jiang Xiaoyan, Wiedinmyer C, Carlton A G. Aerosols from fires:An examination of the effects on ozone photochemistry in the Western United States[J]. Environmental Science & Technology, 2012, 46(21):11878-11886.
[5] Lu Hui, Wei Wenshou, Liu Mingzhe, et al. Aerosol optical absorption by dust and black carbon in Taklimakan Desert, during no-dust and dust-storm conditions[J]. Particuology, 2012, 10(4):509-516.
[6] Massabò D, Caponi L, Bernardoni V, et al. Multi-wavelength optical determination of black and brown carbon in atmospheric aerosols[J]. Atmospheric Environment, 2015, 108:1-12.
[7] Kirchstetter T W, Novakov T, Hobbs P V. Evidence that the spectral dependence of light absorption by aerosols is affected by organic carbon[J]. Journal of Geophysical Research:Atmospheres, 2004. DOI:10.1029/2004JD004999.
[8] Saleh R, Hennigan C J, Mcmeeking G R, et al. Absorptivity of brown carbon in fresh and photo-chemically aged biomass-burning emissions[J]. Atmospheric Chemistry and Physics, 2013, 13(15):7683-7693.
[9] Cheng Yuan, He Kebin, Zheng Mei, et al. Optical properties of elemental carbon and water-soluble organic carbon in Beijing, China[J]. Atmospheric Chemistry and Physics Discussions, 2011,11(2):11497-11510.
[10] Miyazaki Y, Kondo Y, Han S, et al. Chemical characteristics of water-soluble organic carbon in the Asian outflow[J]. Journal of Geophysical Research:Atmospheres, 2007, 112(D22):22-30.
[11] Andreae M O, Gelencsér A. Black carbon or brown carbon? The nature of light-absorbing carbonaceous aerosols[J]. Atmospheric Chemistry and Physics, 2006, 6(10):3131-3148.
[12] Graber E R, Rudich Y. Atmospheric HULIS:How humic-like are they? A comprehensive and critical review[J]. Atmospheric Chemistry and Physics, 2006, 6(3):729-753.
[13] Garg S, Chandra B P, Sinha V, et al. Limitation of the use of the absorption angstrom exponent for source apportionment of equivalent black carbon:a case study from the North West Indo-Gangetic Plain[J]. Environmental Science & Technology, 2015, 50(2):814-824.
[14] Herich H, Hueglin C, Buchmann B. A 2.5 year's source apportionment study of black carbon from wood burning and fossil fuel combustion at urban and rural sites in Switzerland[J]. Atmospheric Measurement Techniques, 2011, 4(7):1409.
[15] Shen Guofeng, Chen Yuanchen, Wei Siye, et al. Mass absorption efficiency of elemental carbon for source samples from residential biomass and coal combustions[J]. Atmospheric Environment, 2013, 79(11):79-84.
[16] Singh A, Rajput P, Sharma D, et al. Black carbon and elemental carbon from postharvest agricultural-waste burning emissions in the Indo-Gangetic Plain[J]. Advances in Meteorology, 2014, 2014(1):1-12.
[17] Arnott W P, Hamasha K, Moosmüller H, et al. Towards aerosol light-absorption measurements with a 7-wavelength aethalometer:Evaluation with a photoacoustic instrument and 3-wavelength nephelometer[J]. Aerosol Science and Technology, 2005, 39(1):17-29.
[18] Xu Jianzhong, Zhang Qi, Chen Min, et al. Chemical composition, sources, and processes of urban aerosols during summertime in northwest China:insights from high-resolution aerosol mass spectrometry[J]. Atmospheric Chemistry and Physics, 2014, 14(23):12593-12611.
[19] Zhang Kai, Li XingJie, Yang Wei, et al. Ambient PM_2.5 level and its constituent in heating period in Chengguan District, Lanzhou City and its influence on birth quality of mice[J]. Journal of Glaciology and Geocryology, 2016, 38(6):1718-1723.[张凯, 李兴杰, 杨蔚, 等. 兰州市城关区采暖期大气PM_2.5成分分析及对子代小鼠的影响研究[J]. 冰川冻土, 2016, 38(6):1718-1723.]
[20] Chen Leihua, Yu Ye, Chen Jinbei, et al. Characteristics of main air pollution in Lanzhou during 2001-2007[J]. Plateau Meteorology, 2010, 29(6):1627-1633.[陈雷华, 余晔, 陈晋北, 等. 2001-2007年兰州市主要大气污染物污染特征分析[J]. 高原气象, 2010, 29(6):1627-1633.]
[21] Liu Lichen, Cheng Yanfang, Liu Yongchang. Study of the implementation and countermeasures of China's environmental management system from 2001 to 2010[J]. Journal of Glaciology and Geocryology, 2015, 37(6):1708-1716.[刘理臣, 程艳芳, 刘永畅. 2001-2010年我国环境管理制度执行情况研究及对策措施[J]. 冰川冻土, 2015, 37(6):1708-1716.]
[22] Wang Xin, Xu Baiqing, Ming Jing. An overview of the studies on black carbon and mineral dust deposition in snow and ice cores in East Asia[J]. Journal of Meteorological Research, 2014, 28(3):354-370.
[23] Ming Jing, Qin Dahe, Xiao Cunde. Black carbon in snow and ice:a review[J]. Journal of Glaciology and Geocryology, 2005, 27(4):539-544.[明镜, 秦大河, 效存德. 雪冰中的黑碳记录研究的历史回顾[J]. 冰川冻土, 2005, 27(4):539-544.]
[24] Yang Fumo, Tan Jihua, Zhao Qing, et al. Characteristics of PM2.5 speciation in representative megacities and across China[J]. Atmospheric Chemistry and Physics, 2011, 11(11):5207-5219.
[25] Yu Ye, Xia Dunsheng, Chen Leihua, et al. Analysis of particulate pollution characteristics and its causes in Lanzhou, Northwest China[J]. Environmental Science, 2010, 31(1):22-28.[余晔, 夏敦胜, 陈雷华, 等. 兰州市PM10污染变化特征及其成因分析[J]. 环境科学, 2010, 31(1):22-28.]
[26] Zhao Suping, Yu Ye, Yin Daiying, et al. Effective density of submicron aerosol particles in a typical valley city, western China[J]. Aerosol Air Qual. Res, 2017, 17:1-13.
[27] Schwarz J P, Gao RuShan, Fahey D W, et al. Single-particle measurements of midlatitude black carbon and light-scattering aerosols from the boundary layer to the lower stratosphere[J]. Journal of Geophysical Research:Atmospheres, 2006. DOI:10.1029/2006JD007076.
[28] Sun Yele, Zhang Qi, Schwab J J, et al. Characterization of the sources and processes of organic and inorganic aerosols in New York City with a high-resolution time-of-flight aerosol mass spectrometer[J]. Atmospheric Chemistry and Physics Discussions, 2010, 10(10):22669-22723.
[29] Xu Jianzhong, Zhang Qi, Wang Zebin, et al. Chemical composition and size distribution of summertime PM 2.5 at a high altitude remote location in the northeast of the Qinghai-Xizang (Tibet) Plateau:insights into aerosol sources and processing in free troposphere[J]. Atmospheric Chemistry and Physics, 2015, 15(9):5069-5081.
[30] Weingartner E, Saathoff H, Schnaiter M, et al. Absorption of light by soot particles:determination of the absorption coefficient by means of aethalometers[J]. Journal of Aerosol Science, 2003, 34(10):1445-1463.
[31] Yang Mingxi, Howell S G, Zhuang J, et al. Attribution of aerosol light absorption to black carbon, brown carbon, and dust in China-interpretations of atmospheric measurements during EAST-AIRE[J]. Atmospheric Chemistry and Physics, 2009, 9(6):2035-2050.
[32] Paatero P, Tapper U. Positive matrix factorization:A non-negative factor model with optimal utilization of error estimates of data values[J]. Environmetrics, 1994, 5(2):111-126.
[33] Schmid O, Artaxo P, Arnott W P, et al. Spectral light absorption by ambient aerosols influenced by biomass burning in the Amazon Basin. I:Comparison and field calibration of absorption measurement techniques[J]. Atmospheric Chemistry and Physics, 2006, 6(11):3443-3462.
[34] Shamjad P M, Tripathi S N, Pathak R, et al. Contribution of brown carbon to direct radiative forcing over the indo-gangetic plain[J]. Environmental Science & Technology, 2015, 49(17):10474-10481.
[35] Hoffer A, Gelencs R A, Guyon P, et al. Optical properties of humic-like substances (HULIS) in biomass-burning aerosols[J]. Atmospheric Chemistry and Physics, 2006, 6(11):3563-3570.
[36] Zhong Min, Jang M. Dynamic light absorption of biomass-burning organic carbon photochemically aged under natural sunlight[J]. Atmospheric Chemistry and Physics, 2014, 14(3):1517-1525.
[37] Sun Yele, Jiang Qi, Wang Zifa, et al. Investigation of the sources and evolution processes of severe haze pollution in Beijing in January 2013[J]. Journal of Geophysical Research:Atmospheres, 2014, 119(7):4380-4398.
[38] Wu Yunfei, Zhang Renjian, Tian Ping, et al. Effect of ambient humidity on the light absorption amplification of black carbon in Beijing during January 2013[J]. Atmospheric Environment, 2016, 124(1):217-223.
[39] Forrister H, Liu J, Scheuer E, et al. Evolution of brown carbon in wildfire plumes[J]. Geophysical Research Letters, 2015, 42(11):4623-4630.
[40] Washenfelder R A, Attwood A R, Brock C A, et al. Biomass burning dominates brown carbon absorption in the rural southeastern United States[J]. Geophysical Research Letters, 2015, 42(2):653-664.
[41] Yuan Jinfeng, Huang Xiaofeng, Cao Liming, et al. Light absorption of brown carbon aerosol in the PRD region of China[J]. Atmospheric Chemistry and Physics, 2016, 16(3):1433-1443.
[42] Bahadur R, Praveen P S, Xu Yangyang, et al. Solar absorption by elemental and brown carbon determined from spectral observations[J]. Proceedings of the National Academy of Sciences, 2012, 109(43):17366-17371.
[43] Zhang Xiaolu, Kim H, Parworth C L, et al. Optical properties of wintertime aerosols from residential wood burning in Fresno, CA:Results from DISCOVER-AQ 2013[J]. Environmental Science & Technology, 2016, 50(4):1681-1690.
[44] Liu Dantong, Taylor J W, Young D E, et al. The effect of complex black carbon microphysics on the determination of the optical properties of brown carbon[J]. Geophysical Research Letters, 2015, 42(2):613-619.