References

ACP

Atmospheric Chemistry and Physics

ACP

1680-7324

Copernicus GmbH

Göttingen, Germany

10.5194/acp-8-6665-2008

Estimation of the mass absorption cross section of the organic carbon component of aerosols in the Mexico City Metropolitan Area

Barnard

J. C.

¹ Volkamer

² Kassianov

E. I.

Pacific Northwest National Laboratory, Richland, Washington, USA

University of Colorado, Boulder, Colorado, USA

19 11 2008

8 22 6665 6679

This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

This article is available from http://www.atmos-chem-phys.net/8/6665/2008/acp-8-6665-2008.html

The full text article is available as a PDF file from http://www.atmos-chem-phys.net/8/6665/2008/acp-8-6665-2008.pdf

Data taken from the MCMA-2003 and the 2006 MILAGRO field campaigns are used to examine the absorption of solar radiation by the organic component of aerosols. Using irradiance data from a Multi-Filter Rotating Shadowband Radiometer (MFRSR) and an actinic flux spectroradiometer (SR), we derive aerosol single scattering albedo, ϖ0, λ, as a function of wavelength, λ. We find that in the near-UV spectral range (250 to 400 nm) ϖ0, λ is much lower compared to ϖ0, λ at 500 nm indicating enhanced absorption in the near-UV range. Absorption by elemental carbon, dust, or gas cannot account for this enhanced absorption leaving the organic carbon component of the aerosol (OA) as the most likely absorber. We use data from a surface deployed Aerodyne Aerosol Mass Spectrometer (AMS) along with the inferred ϖ0, λ to estimate the Mass Absorption Cross section (MAC) for the organic aerosol. We find that the MAC is about 10.5 m2/g at 300 nm and falls close to zero at about 500 nm; values that are roughly consistent with other estimates of organic aerosol MAC. These MAC values can be considered as "radiatively correct", because when used in radiative transfer calculations, the calculated irradiances/actinic fluxes match those measured at the wavelengths considered here. For an illustrative case study described here, we estimate that the light absorption by the "brown" (organic) carbonaceous aerosol can add about 40% to the light absorption of black carbon in Mexico City. This contribution will vary depending on the relative abundance of organic aerosol relative to black carbon. Furthermore, our analysis indicates that organic aerosol would slow down photochemistry by selectively scavenging the light reaching the ground at those wavelengths that drive photochemical reactions. Finally, satellite retrievals of trace gases that are used to infer emissions currently assume that the MAC of organic carbon is zero. For trace gases that are retrieved using wavelengths shorter then 420 nm (i.e. SO2, HCHO, halogenoxides, NO2), the assumption of non-zero MAC values will induce an upward correction to the inferred emissions. This assumption will be particularly relevant in polluted urban atmospheres and areas of biomass burning where organic aerosols are particularly abundant.

References 1

Alexander, D. T. L., Crozier, P. A., and Anderson, J. R.: Brown carbon spheres in East Asian outflow and their optical properties, Science, 321, 833–835, 2008.

Alexandrov, M. D., Kiedron, P., Michalsky, J. J., Hodges, G., Flynn, C. J., and Lacis, A. A.: Optical depth measurements by shadow-band radiometers and their uncertainties, Appl. Optics, 46(33), 8027–8038, 2007.

Alfaro, S. C., Lafon. S., Rajot, J. L, Formenti, P., Gaudichet, A., and Maillé, M.: Iron oxides and light absorption by pure desert dust: An experimental study, J. Geophys. Res., 109, D08208, doi:1010.29/2003JD004374, 2004.

Andreae, M. O. and Gelencsér, A.: Black carbon or brown carbon? The nature of light-absorbing carbonaceous aerosols, Atmos. Chem. Phys., 6, 3131–3148, 2006.

Arnott, W. P., Moosmuller, H., Rogers, C. F., Jin, T., and Bruch, R.: Photoacoustic spectrometer for measuring light absorption by aerosols: Instrument description, Atmos. Environ., 33, 2845–2852, 1999.

Barnard, J. C., Kassianov, E. I., Ackerman, T. P., Frey, S., Johnson, K., Zuberi, B., Molina, L. T., Molina, M. J., Gaffney, J. S., and Marley, N. A.: Measurements of Black Carbon Specific Absorption in the Mexico City Metropolitan Area during the MCMA 2003 Field Campaign, Atmos. Chem. Phys. Discuss., 5, 4083–4113, 2005.

Beirle, S., Platt, U., Wenig, M., and Wagner, T.: Highly resolved global distribution of tropospheric \chemNO_2 using GOME narrow swath mode data, Atmos. Chem. Phys., 4, 1913–1924, 2004.

Bergstrom, R. W., Russell, P. B., and Hignett, P.: Wavelength dependence of absorption of black carbon particles: Predictions and results from the TARFOX experiment and implications for the aerosol single scattering albedo, J. Atmos. Sci., 59, 567–577, 2002.

Bergstrom, R. W., Pilewskie, P., Russell, P. B., Redemann, J., Bond, T. C., Quinn, P. K., and Sierau, B.: Spectral absorption properties of atmospheric aerosols, Atmos. Chem. Phys., 7, 5937–5943, 2007.

Bohren, C. F. and Huffman, D. R.: Absorption and Scattering of Light by Small Particles, John Wiley & Sons, New York, USA, 544~pp., 1983.

Bond, T. C., Bussemer, M., Wehner, B., Keller, S., Charlson, R. J., and Heintzenberg, J.: Light absorption by primary particle emissions from a lignite burning plant, Environ. Sci. Technol., 33, 3887–3891, 1999.

Bond, T. C. and Bergstrom, R. W.: Light absorption by carbonaceous particles: An investigative review, Aerosol Sci. Technol., 40, 27–67, 2006.

Bond, T. C., Habib, G., and Bergstrom, R. W.: Limitations in the enhancement of visible light absorption due to mixing state, J. Geophys. Res., 111, D20211, doi:10.1209/2006JD007315, 2006.

Cappa, C., Lack, D. A., Burkholder, J. B., and Ravishankara, A. R.: Bias in filter-based aerosol absorption measurements due to organic aerosol loading: Evidence from laboratory measurements, Aerosol Sci. Tech., 42(12), 1022–1032, 2008.

Castro, T., Ruiz-Suarez, L. G., Ruiz-Suarez, J. C., Molina, M. J., and Montero, M.: Sensitivity analysis of a UV radiation transfer model and experimental photolysis rates of \chemNO_2 in the atmosphere of Mexico City, Atmos. Environ., 31, 609–620, 1997.

Castro, T., Madronich, S., Rivale, S., Muhlia, A., and Mar, B.: The influence of aerosols on photochemical smog in Mexico City, Atmos. Environ., 35, 1765–1772, 2001.

Cede, A., Herman, J., Richter, A., Krotkov, N., and Burrows, J.: Measurements of nitrogen dioxide total column amounts using a Brewer double spectrometer in direct Sun mode, J. Geophys. Res., 111, D05304, doi:10.1029/2005JD006585, 2006.

Clarke, A., McNaughton, C., Kapustin, V., Shinozuka, Y., Howell, S., Dibb, J., Zhou, J., Anderson, B., Brekhovskikh, V., Turner, H., and Pinkerton, M.: Biomass burning and pollution aerosol over North America: Organic components and their influence on spectral optical properties and humidification response, J. Geophys. Res., 112, D12S18, doi:10.1029/2006JD007777, 2007.

Coddington, O., Schmidt, K. S., Pilewskie, P., Gore, W. J., Bergstrom, R. W., Román, M. O., Redemann, J., Russell, P. B., Liu, J., and Schaaf, C. B.: Aircraft measurements of spectral surface albedo and its consistency with ground-based and space-borne observations, J. Geophys. Res., 113, D17209, doi:10.1029/2008JD010089, 2008.

de~Foy, B., Varela, J. R., Molina, L. T., and Molina, M. J.: Rapid ventilation of the Mexico City basin and regional fate of the urban plume, Atmos. Chem. Phys., 6, 2321–2335, 2006.

de~Foy, B., Lei, W., Zavala, M., Volkamer, R., Samuelsson, J., Mellqvist, J., Galle, B., Martínez, A.-P., Grutter, M., Retama, A., and Molina, L. T.: Modelling constraints on the emission inventory and on vertical dispersion for CO and \chemSO_2 in the Mexico City Metropolitan Area using Solar FTIR and zenith sky UV spectroscopy, Atmos. Chem. Phys., 7, 781–801, 2007.

Denkenberger, K. A., Moffet, R. C., Holecek, J. C., Rebotier, T. P., and Prather, K. A.: Real-time, single-particle measurements of oligomers in aged ambient aerosol particles, Environ. Sci. Technol., 41, 5439–5446, 2007.

Doran, J. C., Barnard, J. C., Arnott, W. P., Cary, R., Coulter, R., Fast, J. D., Kassianov, E. I., Kleinman, L., Laulainen, N. S., Martin, T., Paredes-Miranda, G., Pekour, M. S., Shaw, W. J., Smith, D. F., Springston, S. R., and Yu, X.-Y.: The T1-T2 study: evolution of aerosol properties downwind of Mexico City, Atmos. Chem. Phys., 7, 1585–1598, 2007.

Doran, J. C., Fast, J. D., Barnard, J. C., Laskin, A., Desyaterik, Y., and Gilles, M. K.: Applications of lagrangian dispersion modeling to the analysis of changes in the specific absorption of elemental carbon, Atmos. Chem. Phys., 8, 1377–1389, 2008.

Dubovik, O., Holben, B., Eck, T. F., Smirnov, A., Kaufman, Y. J., King, M. D., Tanré, D., and Slutsker, I.: Variability of absorption and optical properties of key aerosol types observed in worldwide locations, J. Atmos. Sci., 59, 590–608, 2002.

Fast, J. D., de~Foy, B., Acevedo~Rosas, F., Caetano, E., Carmichael, G., Emmons, L., McKenna, D., Mena, M., Skamarock, W., Tie, X., Coulter, R. L., Barnard, J. C., Wiedinmyer, C., and Madronich, S.: A meteorological overview of the MILAGRO field campaigns, Atmos. Chem. Phys., 7, 2233–2257, 2007.

Fuller, K. A., Malm, W. C., and Kreidenweis, S. M.: Effects of mixing on extinction by carbonaceous particles, J. Geophys. Res., 104(D13), 15 941–15 954, 1999.

Goering, C. D., L'Ecuyer, T. S., Stephens, G. L., Slusser, J. R., Scott, G., Davis, J., Barnard, J. C., and Madronich, S.: Simultaneous retrievals of column ozone and aerosol optical properties from direct and diffuse solar irradiance measurements, J. Geophys. Res., 110, D05204, doi:10.1029/2004JD005330, 2005.

Goody, R. M. and Yung, Y. L.: Atmospheric Radiation Theoretical Basis, Second Edition, Oxford University Press, Oxford, UK, 519~pp., 1989.

Hansen, A. D. A., Rosen, H., and Novakov, T.: The aethalometer – An instrument for the real-time measurement of optical absorption by aerosol particles, Sci. Total Environ., 36, 191–196, 1984.

Harrison, L., Michalsky, J., and Berndt, J.: Automated multifilter rotating shadow-band radiometer: an instrument for optical depth and radiation measurements, Appl. Optics, 33, 5118–5125, 1994.

Heue, K.-P., Richter, A., Bruns, M., Burrows, J. P., v Friedeburg, C., Platt, U., Pundt, I., Wang, P., and Wagner, T.: Validation of SCIAMACHY tropospheric \chemNO_2-columns with AMAXDOAS measurements, Atmos. Chem. Phys., 5, 1039–1051, 2005.

Hoffer, A., Gelencsér, A., Guyon, P., Kiss, G., Schmid, O., Frank, G. P., Artaxo, P., and Andreae, M. O.: Optical properties of humic-like substances (HULIS) in biomass-burning aerosols, Atmos. Chem. Phys., 6, 3563–3570, 2006.

IPCC: The physical basis of climate change: Changes in atmospheric constituents and in radiative forcing, 2007.

Jacobson, M. Z.: Isolating nitrated and aromatic aerosols and nitrated aromatic gases as sources of ultraviolet light absorption, J. Geophys. Res., 104(D3), 3527–3542, 1999.

Jayne, J. T., Leard, D. C., Zhang, X., Davidovits, P., Smith, K. A., Kolb, C. E., and Worsnop, D. R.: Development of an Aerosol Mass Spectrometer for size and composition analysis of sub-micron particles, Aerosol Sci. Tech., 33, 49–70, 2000.

Jeong, C.-H., Hopke, P. K., Kim, E., and Lee, D.-W.: The comparison between thermal – optical transmittance elemental carbon and Aethalometer black carbon measured and multiple monitoring sites, Atmos. Environ., 38, 5193–5204, 2004.

Jimenez, J. L., Jayne, J. T., Shi, Q., Kolb, C. E., Worsnop, D. R., Yourshaw, I., Seinfeld, J. H., Flagan, R. C., Zhang, X., Smith, K. A., Morris, J., and Davidovits, P.: Ambient aerosol sampling using Aerodyne Aerosol Mass Spectrometer, J. Geophys. Res., 108, 8425, doi:10.1029/2001JD001213, 2003.

Johnson, K. S., Zuberi, B., Molina, L. T., Molina, M. J., Iedema, M. J., Cowin, J. P., Gaspar, D. J., Wang, C., and Laskin, A.: Processing of soot in an urban environment: case study from the Mexico City Metropolitan Area, Atmos. Chem. Phys., 5, 3033–3043, 2005.

Kassianov, E. I., Flynn, C. J., Ackerman, T. P., and Barnard, J. C.: Aerosol single-scattering albedo and asymmetry parameter from MFRSR observations during the ARM Aerosol IOP 2003, Atmos. Chem. Phys., 7, 3341–3351, 2007.

Kirchstetter, T. W., Novakov, T., and Hobbs, P.: Evidence that the spectral dependence of light absorption by aerosols is affected by organic carbon, J. Geophys. Res., 109, D21208, doi:10.1029/2004JD004999, 2004.

Kirchstetter, T. W. and Novakov, T.: Controlled generation of black carbon particles from a diffusion flame and applications in evaluating black carbon, Atmos. Environ., 41(9), 1874–1888, doi:10.1016/j.atmosenv.2006.10.067, 2007.

Kraus, A., and Hofzumahaus, A.: Field measurements of atmospheric photolysis frequencies for \chemO_3, \chemNO_2, HCHO, \chemCH_3CHO, \chemH_2O_2, and HONO by UV spectroradiometry, J. Atmos. Chem., 31, 161–180, 1998.

Kraus, A., Rohrer, F., and Hofzumahaus, A.: Intercomparison of NO2 photolysis frequency measurements by actinic flux spectroradiometry and chemical actinometry during JCOM97, Geophys. Res. Lett., 27, 1115–1118, 2000.

Krotkov, N., Bharta, P. K., Herman, J., Slusse, J., Scott, G., Labow, G., Vasilkov, A. P., Eck, T. F., Dubovik, O., and Holben, B. N.: Aerosol ultraviolet absorption experiment (2002 to 2004), part 2: absorption optical thickness, refractive index, and single scattering albedo, Opt. Eng., 44(4), 041005, doi:10.1117/12.638983, 2005.

Lack, D. A., Cappa, C. D., Baynard, T., Massoli, P., Covert, D. S., Sierau, B., Bates, T. S., Quinn, P. K., Lovejoy, E. R., and Ravishankara, A. R.: Bias in filter-based aerosol absorption measurements due to organic aerosol loading: Evidence from ambient sampling, Aerosol Sci. Tech., 42(12), 1033–1041, 2008.

Lei, W., de~Foy, B., Zavala, M., Volkamer, R., and Molina, L. T.: Characterizing ozone production in the Mexico City Metropolitan Area: a case study using a chemical transport model, Atmos. Chem. Phys., 7, 1347–1366, 2007.

Lewis, K., Arnott, W. P., Moosmüller, H., and Wold, C. E.: Strong spectral variation of wood smoke light absorption and single scattering albedo observed in-situ using a novel dual wavelength photoacoustic instrument, J. Geophys. Res, 113, D16203, doi:10.1029/2007JD009699, 2008.

Linke, C., Möhler, O., Veres, A., Mohácsi, Á., Bozóki, Z., Szabó, G., and Schnaiter, M.: Optical properties and mineralogical composition of different Saharan mineral dust samples: a laboratory study, Atmos. Chem. Phys., 6, 3315–3323, 2006.

Long, C. N. and Ackerman, T. P.: Identification of clear skies from broadband pyranometer measurements and calculation of downwelling shortwave cloud effects, J. Geophys. Res., 105(D12), 15 609–15 626, 2000.

Michalsky, J. J., Schlemmer, J. A., Berkheiser, W. E., Berndt, J. L., Harrison, L. C., Laulainen, N. S., Larson, N. R., and Barnard, J. C.: Multi-year measurements of aerosol optical depth in the atmospheric radiation measurement and quantitative links programs, J. Geophys. Res., 106(D11), 12 099–12 107, 2001.

Michalsky, J. J. and Kiedron, P. W.: Comparison of UV-RSS spectral measurements and TUV model runs for clear skies for the May 2003 ARM aerosol intensive observation period, Atmos. Chem. Phys., 8, 1813–1821, 2008.

Molina, L. T., Kolb, C. E., de~Foy, B., Lamb, B. K., Brune, W. H., Jimenez, J. L., Ramos-Villegas, R., Sarmiento, J., Paramo-Figueroa, V. H., Cardenas, B., Gutierrez-Avedoy, V., and Molina, M. J.: Air quality in North America's most populous city - overview of the MCMA-2003 campaign, Atmos. Chem. Phys., 7, 2447–2473, 2007.

Ramanathan, V., Li, F., Ramana, M. V., Praveen, P. S., Kim, D., Corrigan, C. E., Nguyen, H., Stone, E. A., Schauer, J. J., Carmichael, G. R., Adhikary, B., and Yoon, S. C.: Atmospheric brown clouds: Hemispherical and regional variations in long-range transport, absorption, and radiative forcing, J. Geophys. Res., 112, D22S21, doi:10.1029/2006JD008124, 2007.

Ricchiazzi, P., Yang, S., Gautier, C., and Sowle, D.: SBDART: A research and teaching software tool for plane-parallel radiative transfer in the Earth's atmosphere, B. Am. Meteorol. Soc., 79(10), 2101–2114, 1998.

Roden, C. A., Bond, T. C., Conway, S., and Pinel, A. B. O.: Emission factors and real-time optical properties for particles emitted from traditional wood burning cook stoves, Environ. Sci. Technol., 40, 6750–6757, 2006.

Salcedo, D., Onasch, T. B., Dzepina, K., Canagaratna, M. R., Zhang, Q., Huffman, J. A., DeCarlo, P. F., Jayne, J. T., Mortimer, P., Worsnop, D. R., Kolb, C. E., Johnson, K. S., Zuberi, B., Marr, L. C., Volkamer, R., Molina, L. T., Molina, M. J., Cardenas, B., Bernab�, R. M., Márquez, C., Gaffney, J. S., Marley, N. A., Laskin, A., Shutthanandan, V., Xie, Y., Brune, W., Lesher, R., Shirley, T., and Jimenez, J. L.: Characterization of ambient aerosols in Mexico City during the MCMA-2003 campaign with Aerosol Mass Spectrometry: results from the CENICA Supersite, Atmos. Chem. Phys., 6, 925–946, 2006.

San~Martini, F. M., Dunlea, E. J., Volkamer, R., Onasch, T. B., Jayne, J. T., Canagaratna, M. R., Worsnop, D. R., Kolb, C. E., Shorter, J. H., Herndon, S. C., Zahniser, M. S., Salcedo, D., Dzepina, K., Jimenez, J. L., Ortega, J. M., Johnson, K. S., McRae, G. J., Molina, L. T., and Molina, M. J.: Implementation of a Markov Chain Monte Carlo method to inorganic aerosol modeling of observations from the MCMA-2003 campaign - Part~II: Model application to the CENICA, Pedregal and Santa Ana sites, Atmos. Chem. Phys., 6, 4889–4904, 2006.

Schnaiter, M., Gimmler, M., Llamas, I., Linke, C., Jäger, C., and Mutschke, H.: Strong spectral dependence of light absorption by organic carbon particles formed by propane combustion, Atmos. Chem. Phys., 6, 2981–2990, 2006.

Schuster, G. L., Dubovik, O., Holben, B. N., and Clothiaux, E. E.: Inferring the black carbon content and specific absorption from AERONET retrievals, J. Geophys. Res., 101, D10S17, doi:10.1029/2004JD004548, 2005.

Seinfeld, J. H.: Black carbon and brown clouds, Nature Geoscience, 1, 15, 2008.

Singh, H. B., Brune, W. H., Crawford, J. H., Jacob, D. J., and Russell, P. B.: Overview of the summer 2004 Intercontinental Chemical Transport Experiment – North America (INTEX – A), J. Geophys. Res., 111, D24S01, doi:10.1029/2006JD007905, 2006.

Sokolik, I. N. and Toon, O. B.: Incorporation of mineralogical composition of aerosols into models of radiative properties of mineral aerosol from the UV to IR wavelengths, J. Geophys. Res., 104(D8), 9423–9444, 1999.

Subramanian, R., Roden, C. A., Boparai, P., and Bond, T. C.: Yellow beads and missing particles: Trouble ahead for filter-based absorption measurements, Aerosol Sci. Tech. 41, 630–637, 2007.

Sun, H., Biedermann, L., and Bond, T. C.: The color of brown carbon: A model for ultraviolet and visible light absorption by organic carbon aerosol, Geophys. Res. Lett., 34, L17813, doi:10.1029/2007GL029797, 2007.

Turpin, B. J. and Lim, H.-J.: Species contributions to PM$_2.5$ mass concentrations: Revisiting common assumptions for estimating organic mass, Aerosol Sci. Tech., 35, 602–610, 2001.

Wagner, F. and Silva, A. M.: Some considerations about Ångström exponent distributions, Atmos. Chem. Phys., 8, 481–489, 2008.

Wenny, B. N., Schafer, J. S., DeLuisi, J. J., Saxena, V. K., Barnard, W. F., Petropavlovskikh, I. V., and Vergamini, A. J.: A study of regional radiative properties and effects on ultraviolet-B radiation, J. Geophys. Res., 103(D14), 18083–17097, 1998.

Volkamer, R., Molina, L. T., Molina, M. J., Shirley, T., and Brune, W. H.: DOAS measurement of glyoxal as an indicator for fast VOC chemistry in urban air, Geophys. Res. Lett., 32, L08806, doi:10.1029/2005GL022616, 2005.

Volkamer, R., Jimenez, J. L., San~Martini, F., Dzepina, K., Zhang, Q., Salcedo, D., Molina, L. T., Worsnop, D. R., and Molina, M. J.: Secondary organic aerosol formation from anthropogenic air pollution: Rapid and higher than expected, Geophys. Res. Lett., 33, L17811, doi:10.1029/2006GL026899, 2006.

Volkamer, R., San~Martini, F., Salcedo, D., Molina, L. T., Jimenez, J. L., and Molina, M. J.: A missing sink for gas-phase gloxal in Mexico City: Formation of secondary organic aerosol, Geophys. Res. Lett., 34, L19807, doi:10.1029/2007GL030752, 2007a.

Volkamer, R., Sheehy, P. M., Molina, L. T., and Molina, M. J.: Oxidative capacity of the Mexico City atmosphere � Part 1: A radical source perspective, Atmos. Chem. Phys. Discuss., 7, 5365–5412, 2007.