References

ACPD

Atmospheric Chemistry and Physics Discussions

ACPD

1680-7375

Copernicus GmbH

Göttingen, Germany

10.5194/acpd-7-14989-2007

Applications of Lagrangian dispersion modeling to the analysis of changes in the specific absorption of elemental carbon

Doran

J. C.

¹ Fast

J. D.

¹ Barnard

J. C.

¹ Laskin

¹ Desyaterik

¹ Gilles

M. K.

² Hopkins

R. J.

Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington, USA

Lawrence Berkeley National Laboratory, Berkeley, CA, USA

19 10 2007

7 5 14989 15023

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We use a Lagrangian dispersion model driven by a mesoscale model with four-dimensional data assimilation to simulate the dispersion of elemental carbon (EC) over a region encompassing Mexico City and its surroundings, the study domain for the 2006 MAX-MEX experiment, which was a component of the MILAGRO campaign. The results are used to identify periods when biomass burning was likely to have had a significant impact on the concentrations of elemental carbon at two sites, T1 and T2, downwind of the city, and when emissions from the Mexico City Metropolitan Area (MCMA) were likely to have been more important. They are also used to estimate the median ages of EC affecting the specific absorption of light, αABS, at 870 nm as well as to identify periods when the urban plume from the MCMA was likely to have been advected over T1 and T2. Median EC ages at T1 and T2 are substantially larger during the day than at night. Values of αABS at T1, the nearer of the two sites to Mexico City, were smaller at night and increased rapidly after mid-morning, peaking in the mid-afternoon. The behavior is attributed to the coating of aerosols with substances such as sulfate or organic carbon during daylight hours, but such coating appears to be limited or absent at night. Evidence for this is provided by scanning electron microscopy images of aerosols collected at the sampling sites. During daylight hours the values of αABS did not increase with aerosol age for median ages in the range of 1–4 h. There is some evidence for absorption increasing as aerosols were advected from T1 to T2 but the statistical significance of that result is not strong.

References 1

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

Arnott, W. P., Moosmüller, 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.

Arnott, W. P., Moosmüller, H., Sheridan, P. J., Ogren, J. A., Raspert, R., Slaton, W. V., Hand, J. L., Kreidenweis, S. M., and Collett Jr., J. L.: Photoacoustic and filter-based ambient aerosol light absorption measurements: instrument comparisons and the role of relative humidity, J. Geophys. Res., 108, 4034, doi:10.1029/2002JD002165, 2003.

Barnard, J.C., Kassianov, E.I., Ackerman, T.P., Johnson, K., Zuberi, B., Molina L.T., and Molina, M.J.: Estimation of a "radiatively correct" black carbon specific absorption during the Mexico City Metropolitan Area (MCMA) 2003 field campaign, Atmos. Chem. Phys., 7, 1645–1655, 2007.

Baumgardner, D., Raga, G.B., Kok, G., Ogren, J., Rosas, I., Báez, A., and Novakov, T.: On the evolution of aerosol properties at a mountain site above Mexico City, J. Geophys. Res., 105, 22 243–22 253, 2000.

Baumgardner, D., Raga, G., Peralta, O., Rosas, I., Castro, T., Kuhlbusch, T., John, A. , and Petzold, A.: Diagnosing black carbon trends in large urban areas using carbon monoxide measurements, J. Geophys. Res., 107 (D21), 8342, 10.1029/2001JD000626, 2002.

Baumgardner, D., Kok, G. L., and Raga, G. B.: On the diurnal variability of particle properties related to light absorbing carbon in Mexico City, Atmos. Chem. Phys., 7, 2517–2526, 2007.

Birch, M. E. and Cary, R. A.: Elemental carbon-based method for monitoring occupational exposures to particulate diesel exhaust, Aerosol Science and Technology, 25, 221–241, 1996.

Bond, T. C. and Bergstrom, R. W.: Light absorption by carbonaceous particles: an investigative review, Aerosol Sci. Technol., 40, 27–67, doi:10.1080/02786820500421521, 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:10.1029/2006JD007315, 2006.

Burtscher, H., Leonard, A., Steiner, D., Baltensperger, U., and Weber, A.: Aging of combustion particles in the atmosphere – results from a field study in Zürich. Water, Air, and Soil Poll., 68, 137–147, 1993.

Chen, F., and Dudhia, J.: Coupling an advanced land-surface/hydrology model with the Penn State / NCAR MM5 modeling system. Part I: Model description and implementation, Mon. Wea. Rev., 129, 569–585, 2001.

Chen S.-H. and W.-Y. Sun: A one-dimensional time dependent cloud model, J. Meteor. Soc Japan, 80, 99–118, 2002.

Chou, M.-D. and M.J. Suarez: An efficient thermal infrared radiation parameterization for use in general circulation models, NASA Tech. Memo., 104606, 3, 85 pp., 1994.

Cleveland, W. S.: Robust locally weighted regression and smoothing scatterplots, J. Amer. Statist. Assoc., 74, 829–836, 1979.

Croft, B., Lohmann, U., and von Salzen, K: Direct Aerosol Forcing: Calculation from Observables and Sensitivities to Inputs, Atmos. Chem. Phys., 5, 1931–1949, http://www.atmos-chem-phys.net/5/1931/2005/, 2005.

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

Doran, J. C.: Corrigendum to "The T1-T2 study: evolution of aerosol properties downwind of Mexico City", Atmos. Chem. Phys., 7, 1585–1598, 2007, Atmos. Chem. Phys., 7, 2197–2198, 2007.

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

Hong, S.-Y., Noh, Y., and Dudhia, J.: A new vertical diffusion package with an explicit treatment of entrainment processes, Mon. Wea. Rev., 134, 2318–2341, 2006.

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

Jacobson, M. Z. and Seinfeld, J. H.: Evolution of nanoparticle size and mixing state near the point of emission, Atmos. Environ., 38, 1839–1850, 2004.

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.

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

Liu, Y., Bourgeois, A., Warner, T., Swerdlin, S., and Hacker, J.: Implementation of observation-nudging based on FDDA into WRF for supporting AFEC test operations, 6th WRF Conference, NCAR, Boulder, CO, 10.7, 2006.

Mallet, M., Roger, J. C., Despiau, J. P., and Dubovik, O.: A study of the mixing state of black carbon in urban zone, J. Geophys. Res., 109, doi:10.1029/2003JD003940, 2004.

Mann, H. B. and Whitney, D. R.: On a test of whether one of two random variables is stochastically larger than the other, Ann. Math. Stat., 18, 50–60, 1947.

Mlawer, E. J., Taubman, S. J., Brown, P. D., Iacono, M. J., and Clough, S. A.: Radiative transfer for inhomogeneous atmosphere: RRTM, a validated correlated-k model for the longwave, J. Geophys. Res., 102, 16 663–16 682, 1997.

Reid, J. S., Koppmann, R., Eck, T. F., and Eleuterio, D. P.: A review of biomass burning emissions part II: intensive physical properties of biomass burning particles, Atmos. Chem. Phys., 5, 799–825, www.atmos-chem-phys.org/acp/5/799/, 2005.

Riemer, N., Vogel, H., and Vogel, B.: Soot aging time scales in polluted regions during day and night, Atmos. Chem. Phys., 4, 1885–1893, 2004.

Sato, M., Hansen, J., Koch, D., Lacis, A., Ruedy, R., Dubovik, O., Holben, B., Chin, M., and Novakov, T.: Global atmospheric black carbon inferred from AERONET. Proc. Natl. Acad. Sci., 100, 6319–6324, 2003.

Skamarock, W. C., Klemp, J. B., Dudhia, J., Gill, D. O., Barker, D. M., Wang, W., and Powers, J. G.: A description of the advanced research WRF version 2., NCAR Technical Note, NCAR/TN-486+STR, 88 pp., 2005.

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. Geo. Res.-A, 104 (D8), 9423–9444, 1999.

Stauffer, D. R. and Seaman, N.: Multiscale four-dimensional data assimilation, J. Appl. Meteor., 33, 415–434, 1994.

Stohl, A., Forster, C., Frank, A., Seibert, P., and Wotawa, G.: Technical note: The Lagrangian particle dispersion model FLEXPART version 6.2., Atmos. Chem. Phys., 5, 2461–2474, 2005.

Volkhamer, 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.

Watson, J. G., Chow, J. C., and Antony Chen, L.-W.: Summary of organic and elemental carbon/black carbon analysis methods and intercomparisons, Aerosol Air Qual. Res., 5, 65–102, 2005.

Wiedinmyer, C., Quayle, B., Geron, C., Beloe, A., McKenzie, D., Zhang, X., O'Neill, S., and Wynne, K. K.: Estimating emissions from fires in North America for air quality modeling, Atmos. Environ., 40, 3419–3432 2006.

Yokelson, R.,~Urbanski, S., Atlas, E., Toohey, D., Alvarado, E., Crounse, J., Wennberg, P.,~Fisher, M., Wold, C.,~Campos, T., Adachi, K., Buseck, P. R., and Hao, W. M.: Emissions from forest fires near Mexico City, Atmos. Chem. Phys. Discuss., 7, 6687–6718, 2007.

Zhang, Q., Worsnop, D. R., Canagaratna, M. R., and Jimenez, J. L.: Hydrocarbon-like and oxygenated organic aerosols in Pittsburgh: Insights into sources and processes of organic aerosols, Atmos. Chem. Phys., 5, 3289–3311, 2005.