Retrieval of Dust Fraction of Atmospheric Aerosols Based on Spectra Characteristics of Refractive Indices Obtained from Remote Sensing Measurements
WANG Ling1,2, LI Zheng-qiang2*, LI Dong-hui2, LI Kai-tao2, TIAN Qing-jiu1, LI Li2, ZHANG Ying2, Lü Yang2, GU Xing-fa2
1. International Institute for Earth System Science, Nanjing University, Nanjing 210093, China 2. State Environmental Protection Key Laboratory of Satellites Remote Sensing, Institute of Remote Sensing Applications of Chinese Academy of Sciences, Beijing 100101, China
Abstract:Mineral dust is an important chemical component of aerosol, which has a significant impact on the climate and environmental changes. The spectral behavior of aerosol refractive indices at four wavelengths from 440 to 1 020 nm was analyzed based on one year observation obtained from Beijing AERONET site. The real parts of refractive index (n) in each band did not differ greatly, however the imaginary parts (k) showed a significant difference due to the absorption of mineral dust in aerosol. From 440 to 670 nm k decreased rapidly, while from 670 to 1 020 nm featured a lower, constant value. Accordingly, k(440 nm) could be considered separately with other three bands. Hence, we added mineral dust into the currently used three-component aerosol chemical model to form a new four-component model (i.e. BC, AS, dust and water) which is more suitable to represent the aerosol chemical composition. Then we presented a method to retrieve dust content in aerosols using this four-component model and refractive indices obtained from the sunphotometer measurements. Finally the dust content in aerosol was investigated under different weather conditions, i.e. clear, haze and dust in Beijing. The results showed that volume fractions of the dust component were 88%, 37% and 48% for clear, hazy and dusty day respectively, which was consistent with the coarse mode proportion in aerosols calculated from aerosol size distributions.
王 玲1,2, 李正强2*, 李东辉2, 李凯涛2, 田庆久1, 李 莉2, 张 莹2, 吕 阳2, 顾行发2 . 基于遥感观测的折射指数光谱特性反演大气气溶胶中沙尘组分含量 [J]. 光谱学与光谱分析, 2012, 32(06): 1644-1649.
WANG Ling1,2, LI Zheng-qiang2*, LI Dong-hui2, LI Kai-tao2, TIAN Qing-jiu1, LI Li2, ZHANG Ying2, Lü Yang2, GU Xing-fa2. Retrieval of Dust Fraction of Atmospheric Aerosols Based on Spectra Characteristics of Refractive Indices Obtained from Remote Sensing Measurements . SPECTROSCOPY AND SPECTRAL ANALYSIS, 2012, 32(06): 1644-1649.
[1] WANG Hong, SHI Guang-yu, Aoki T, et al(王 宏, 石广玉, Aoki T, 等). Chinese Science Bulletin(科学通报), 2004, 49: 1993. [2] SU Xing-tao, WANG Han-jie, SONG Shuai, et al(宿兴涛, 王汉杰, 宋 帅, 等). Plateau Meteorology(高原气象), 2011, 30: 1300. [3] Kandler K, Benker N, Bundke U, et al. Atmospheric Environment, 2007, 41(37): 8058. [4] Yuan C S, Lee C G, Liu S H. Atmospheric Research, 2006, 82: 663. [5] Schuster G L, Dubovik O, Holben B N, et al. Journal of Geophysical Research, 2005, 110(D10): 1. [6] Dubovik O, et al. Atmos. Meas. Tech., 2011, 4: 975. [7] Dubovik O, Smirnov A, Holben B, et al. Journal of Geophysical Research, 2000, 105(D8): 9791. [8] Schuster G L, Lin B, Dubovik O. Geophys. Res. Lett., 2009, 36(3): 1. [9] Dey S, Tripathi S N, Singh R P, et al. Atmospheric Environment, 2006, 40(3): 445. [10] Hess M, Herd C R. Carbon Black. New York: Mercel Dekker, 1993. [11] Bergstrom R W, Russell P B, Hignett P. Journal of the Atmospheric Sciences, 2002, 59(3): 567. [12] Wagner R, Ajtai T, Kandler K, et al. Atmos. Chem. Phys. Discuss, 2011(11): 21363. [13] Petzold A, Rasp K, Weinzierl B, et al. Tellus B, 2009, 61(1): 118. [14] Müller T, Schladitz A, Massling A, et al. Tellus B, 2009, 61(1): 79. [15] Müller T, Schladitz A, Kandler K, et al. Tellus B, 2011, 63(4): 573. [16] d’Almeida G A, Koepke P, Shettle E P, et al. Atmospheric Aerosols: Global Climatology and Radiative Characteristies: A.Deepak Publishing, Hampton, 1991. [17] Dubovik O, Holben B N, Lapyonok T, et al. Geophys. Res. Lett., 2002, 29(10): 1415. [18] Todd M C, Martins V, Washington R, et al. Journal of Geophysical Research, 2007, 112(D06): 207, doi: 10.1029/2006JD007170. [19] XU Li, FAN Xiao-biao, SHI Guang-yu, et al(许 黎, 樊小标, 石广玉, 等). Acta Meteorologica Sinica(气象学报), 1998, 56(5): 551. [20] Seinfeld J H and Pandis S N. Atmoshperic Chemistry and Physics. New York: Wiley, 1998. [21] Lesins G, Chylek P, Lomann U. Journal of Geophysical Research, 2002, 107 (D10): 4094. [22] Bohren C F and Huffman D R. Absorption and Scattering of Light by Small Particles. New York: Wiley, 1998. [23] Wallace J M and Hobbs P V. AtmosphericScience(大气科学). Translated by HE Jin-hai, WANG Zhen-hui, YIN Yan, et al(何金海, 王振会, 银 燕, 等译). Beijing: Science Press(北京: 科学出版社), 2008. 178. [24] Larson S M, Cass G R, Hussey K J, et al. Environmental Sci. Tech., 1988, 22: 629.