Effects of the physical and optical properties of urban aerosols measured during the CAPITOUL summer campaign on the local direct radiative forcing

Article

Summary

Measurements of aerosol optical and physical properties, and chemical composition were conducted at Toulouse, an urban site of southwest France, as part of the CAPITOUL experiment. A period of intensive observations was held over 10 days during the summer campaign in June–July, 2004. During this period, PM2.5 concentrations ranged between 1 and 50 µg m−3. Aerosol size distributions exhibit the presence of three distinct modes which could be fitted by lognormal functions. Diurnal variations of aerosol concentration, size distribution, BC concentration, scattering and absorption coefficients, and single scattering albedo show the presence of two maxima corresponding to rush hours due to various urban activities such as vehicle traffic. Over the period of study, the single scattering albedo at 0.52 µm is found to be 0.7 ± 0.1, indicating the dominance of absorbing aerosols over Toulouse. Airborne measurements observed the vertical distribution of aerosols in the atmosphere. These observations clearly show that aerosol is mostly contained within the UBL which contributes significantly to the aerosol optical depth. The GAME radiative transfer model (RTM) has been used to carry out the radiative transfer computations. A synergetic approach was applied to generate spectral values of aerosol parameters required as input for the radiative transfer calculations. Vertical radio soundings and airborne measurements provided in-situ parameters required for the RTM. Simulations indicate that aerosols over Toulouse reduce significantly (−30 W m−2) the solar energy reaching the surface, mainly by absorption of the solar radiation into the atmosphere. At the TOA, aerosol forcing is even found to be positive (+0.8 W m−2). These results confirm that local direct aerosol forcing in urban atmosphere is mainly driven by the absorbing black carbon aerosols. The mean heating rate within the UBL is considerably enhanced, by 4.57 K day−1, due to the presence of absorbing aerosols.

References

  1. Ackerman, AS, Toon, OB, Stevens, DE, Heymsfield, AJ, Ramanathan, V, Welton, EJ 2000Reduction of tropical cloudiness by sootSciences28810421047Google Scholar
  2. Anderson, TL, Ogren, JA 1998Determining aerosol radiative properties using the TSI 3563 integrating nephelometerAerosol Sci Tech295769Google Scholar
  3. Anderson, TL, Covert, DS, Wheeler, JD, Harris, JM, Perry, KD, Trost, BE, Jaffe, DJ, Ogren, JA 1999Aerosol backscatter fraction and single scattering albedo: measured values and uncertainties at a coastal station in the Pacific NorthwestJ Geophys Res1042679326808CrossRefGoogle Scholar
  4. Arnott, WP, Hamasha, K, Moosmüller, H, Sheridan, PJ, Ogren, JA 2005Towards aerosol light-absorption measurements with a 7-wavelength aethalometer: Evaluation with a photoacoustic instrument and 3-wavelength nephelometerAerosol Sci Tech391729CrossRefGoogle Scholar
  5. Babu, SS, Satheesh, SK, Moorthy, KK 2002Aerosol radiative forcing due to enhanced black carbon at an urban site in IndiaGeophys Res Lett291880doi: 10.1029/2002GL015826CrossRefGoogle Scholar
  6. Bond, TC, Bergstrom, RW 2006Light absorption by carbonaceous particles; An investigative reviewAerosol Sci Tech402767CrossRefGoogle Scholar
  7. Bond, TC, Anderson, TL, Charlson, RJ 1999Calibration and intercomparison of filter-based measurements of visible light absorption by aerosolsAerosol Sci Tech30582600CrossRefGoogle Scholar
  8. Cachier, H, Aulagnier, F, Sarda, R, Gautier, F, Masclet, P, Besombes, J-L, Marchand, N, Despiau, S, Croci, D, Mallet, M, Laj, P, Marinoni, A, Deveau, P-A, Roger, J-C, Putaud, J-P, Van Dingenen, R, Dell’ Acqua, A, Vidanoga, J, Martins-Dos Santos, S, Liousse, C, Cousin, F, Rosset, R, Gardat, E, Galy-Lacaux, C 2005Aerosol studies during the ESCOMPTE experiment: an overviewAtmos Res74547563CrossRefGoogle Scholar
  9. Calvo, AI, Pont, V, Liousse, C, Dupré, B, Mariscal, A, Zouiten, C, Gardrat, E, Castera, P, Lacaux, CG, Castro, A, Fraile, R 2008Chemical composition of urban aerosols in Toulouse, France during CAPITOUL experimentMeteorol Atmos Phys102307323Google Scholar
  10. Carrico, CM, Rood, MJ, Ogren, JA, Neusüß, C, Wiedensohler, A, Heintzenberg, J 2000Aerosol optical properties at Sagres, Portugal, during ACE 2Tellus Ser B52694716CrossRefGoogle Scholar
  11. Charlson, RJ, Schwartz, SE, Hales, JM, Cess, RD, Coackley, JA, Hansen, JE, Hoffmann, DJ 1992Climate forcing by anthropogenic aerosolsScience255423430CrossRefGoogle Scholar
  12. Chung, CE, Ramanathan, V, Kim, D, Podgorny, IA 2005Global anthropogenic aerosol direct forcing derived from satellite and ground-based observationsJ Geophys Res110D24207doi: 10.1029/2005JD006356CrossRefGoogle Scholar
  13. Dubuisson, P, Buriez, JC, Fouquart, Y 1996High spectral resolution solar radiative transfer in absorbing and scattering media: application to the satellite simulationJ Quant Spectrosc Ra55103126CrossRefGoogle Scholar
  14. Eck, TF, Holben, BN, Reid, JS, Dubovik, O, Smirnov, A, O’Neill, NT, Slutsker, I, Kinne, S 1999Wavelength dependence of the optical depth of biomass burning, urban, and desert dust aerosolsJ Geophys Res1043133331349CrossRefGoogle Scholar
  15. Formenti, P, Boucher, O, Reiner, T, Sprung, D, Andreae, MO, Wendisch, M, Wex, H, Kindred, D, Tzortziou, M, Vasaras, A, Zerefos, C 2002STAAARTE-MED 1998 summer airborne measurements over the Aegean Sea: 2. Aerosol scattering and absorption, and radiative calculationsJ Geophys Res107D4551doi: 10.1029/2001JD001536CrossRefGoogle Scholar
  16. Ganguly, D, Jayaraman, A, Rajesh, TA, Gadhavi, H 2006Wintertime aerosol properties during foggy and nonfoggy days over urban center Delhi and their implications for shortwave radiative forcingJ Geophys Res111D15217doi: 10.1029/2005JD007029CrossRefGoogle Scholar
  17. Hänel, G 1976The properties of atmospheric particles as function of the relative humidity at thermodynamic equilibrium with surrounding moist airAdv Geophys1973188CrossRefGoogle Scholar
  18. Hansen, J, Sato, M, Ruedy, R 1997Radiative forcing and climate responseJ Geophys Res10268316864CrossRefGoogle Scholar
  19. Haywood, JM, Boucher, O 2000Estimates of the direct and indirect radiative forcing due to tropospheric aerosols: a reviewRev Geophys38513543CrossRefGoogle Scholar
  20. Haywood, JM, Ramaswamy, V 1998Global sensitivity studies of the direct radiative forcing due to anthropogenic sulfate and black carbon aerosolsJ Geophys Res10360436058CrossRefGoogle Scholar
  21. Heintzenberg, J, Wiedensohler, A, Tuch, TM, Covert, DS, Sheridan, P, Ogren, JA, Gras, J, Nessler, R, Kleefeld, C, Kalivitis, N 2006Intercomparisons and aerosol calibrations of 12 commercial integrating nephelometers of three manufacturersJ Atmos Ocean Tech23902CrossRefGoogle Scholar
  22. Hess, M, Keopke, P, Schult, I 1998Optical properties of aerosols and clouds: the software package OPACBull Am Meteorol Soc79831844CrossRefGoogle Scholar
  23. Holben, BN, Eck, TF, Slutsker, I, Tanre, D, Buis, JP, Setzer, A, Vermote, E, Reagan, JA, Kaufman, YJ, Nakajima, T, Lavenu, F, Jankowiak, I, Smirnov, A 1998AERONET – A federated instrument network and data archive for aerosol characterizationRemote Sens Environ66116CrossRefGoogle Scholar
  24. Horvarth, H 1993Comparison of measurements of aerosol optical absorption by filter collection and a transmissometric methodAtmos Env27A319325Google Scholar
  25. Intergovernmental Panel on Climate Change et al. 2001

    Climate Change 2001: The Scientific Basis

    Houghton, JT eds. Contribution of Working Group I to the Third Assessment Report of the Intergovernmental Panel on Climate ChangeCambridge Univ. PressNew York944
    Google Scholar
  26. Jacobson, MZ 2001Strong radiative heating due to the mixing state of black carbon in the atmospheric aerosolsNature409695697CrossRefGoogle Scholar
  27. Lacis, AA, Oinas, V 1991A description of the correlated k-distribution methodJ Geophys Res9690279064CrossRefGoogle Scholar
  28. Liousse, C, Cachier, H, Jennings, SG 1993Optical and thermal measurements of black carbon aerosol content in different environments: variation of the specific attenuation cross-sectionAtmos Environ2712031211Google Scholar
  29. Mallet, M, Roger, JC, Despiau, S, Dubovik, O, Putaud, JP 2003Microphysical and optical properties of aerosol particles in urban zone during ESCOMPTEAtmos Res697397CrossRefGoogle Scholar
  30. Mallet, M, Roger, JC, Despiau, S, Putaud, JP, Dubovik, O 2004A study of the mixing state of black carbon in urban zoneJ Geophys Res109D04202doi: 10.1029/2003JD003940CrossRefGoogle Scholar
  31. Mallet, M, Van Dingenen, R, Roger, JC, Despiau, S, Cachier, H 2005In situ airborne measurements of aerosol optical properties during photochemical pollution eventsJ Geophys Res110D03205doi: 10.1029/2004JD005139CrossRefGoogle Scholar
  32. Masson, V, Gomes, L, Pigeon, G, Liousse, C, Pont, V, Lagouarde, J-P, Voogt, J, Salmond, J, Oke, TR, Hidalgo, J, Legain, D, Garrouste, O, Lac, C, Connan, O, Briottet, X, Lachérade, S, Tulet, P 2008The Canopy and Aerosol Particles Interactions in TOulouse Urban Layer (CAPITOUL) experimentMeteorol Appl Phys102135157CrossRefGoogle Scholar
  33. Nunes, TV, Pio, CA 1993Carbonaceous aerosol in industrial and coastal atmospheresAtmos Environ27A13391346Google Scholar
  34. Offenberg, JH, Baker, JE 2000Aerosol size distributions of elemental and organic carbon in urban and over-water atmospheresAtmos Environ3415091517CrossRefGoogle Scholar
  35. Penner, JE, Charlson, RJ, Hales, JM, Laulainen, NS, Leifer, R, Novakov, T, Ogren, J, Radke, LF, Schwartz, SE, Travis, L 1994Quantifying and minimizing uncertainty of climate forcing by anthropogenic aerosolsBull Am Meteorol Soc75375400CrossRefGoogle Scholar
  36. Petzold, A, Kopp, C, Niessner, R 1997The dependence of the specific attenuation cross-section on black carbon mass fraction and particle sizeAtmos Environ31661672CrossRefGoogle Scholar
  37. Pickle, T, Allen, DT, Pratsinis, SE 1990The sources and size distributions of aliphatic and carbonyl carbon in Los Angeles aerosolAtmos Environ2422212228Google Scholar
  38. Ramaswamy, V, Boucher, O, Haigh, J, Hauglustaine, D, Haywood, J, Myhre, G, Nakajima, T, Shi, G, Solomon, S, Betts, RE, Charlson, R, Chuang, CC, Daniel, JS, Del Genio, AD, Feichter, J, Fuglestvedt, J, Forster, PM, Ghan, SJ, Jones, A, Kiehl, JT, Koch, D, Land, C, Lean, J, Lohmann, U, Minschwaner, K, Penner, JE, Roberts, DL, Rodhe, H, Roelofs, G-J, Rotstayn, LD, Schnieder, TL, Schumann, U, Schwartz, SE, Schwartzkopf, MD, Shine, KP, Smith, SJ, Stevenson, DS, Stordal, F, Tegen, I, van Dorland, R, Zhang, Y, Srinivasan, J, Joos, F,  et al. 2001

    Radiative forcing of climate change

    Houghton, JT eds. Climate change 2001: the scientific basisCambridge Univ. PressNew York349416Chap. 6
    Google Scholar
  39. Roger, JC, Mallet, M, Dubuisson, P, Cachier, H, Vermote, E, Dubovik, O, Despiau, S 2006A synergetic approach for estimating the local direct aerosol forcing: application to an urban zone during the ESCOMPTE experimentJ Geophys Res111D13208doi: 10.1029/2005JD006361CrossRefGoogle Scholar
  40. Scott, NA 1974A direct method of computation of the transmission function of an inhomogeneous gaseous medium – I: Description of the methodJ Quant Spectrosc Ra14691704CrossRefGoogle Scholar
  41. Seinfeld, JH, Pandis, SP 1998Atmospheric chemistry and physics: from air pollution to climate change2John WileyHoboken, NJ1326Google Scholar
  42. Singh, S, Nath, S, Kohli, R, Singh, R 2005Aerosols over Delhi during pre-monsoon months: characteristics and effects on surface radiation forcingGeophys Res Lett32L13808doi: 10.1029/2005GL023062CrossRefGoogle Scholar
  43. Smirnov, A, Holben, BN, Eck, TF, Dubovik, O, Slutsker, I 2000Cloud screening and quality control algorithms for the AERONET databaseRem Sens Env73337349CrossRefGoogle Scholar
  44. Stammes, K, Tsay, S, Wiscombe, W, Jayaweera, K 1988Numerically stable algorithm for discrete-ordinate-method radiative transfer in multiple scattering and emitting layered mediaAppl Opt2725022509Google Scholar
  45. Tripathi, SN, Dey, S, Tare, V, Satheesh, SK 2005Aerosol black carbon radiative forcing at an industrial city in northern IndiaGeophys Res Lett32L08802doi: 10.1029/2005GL022515CrossRefGoogle Scholar
  46. Vermote, EF, El Saleous, N, Justice, C 2002Atmospheric correction of the MODIS data in the visible to middle infrared: first resultsRemote Sens Environ8397111CrossRefGoogle Scholar
  47. Weingartner, E, Saathoff, H, Schnaiter, M, Streit, N, Bitnar, B, Baltensperger, U 2003Absorption of light by soot particles; determination of the absorption coefficient by means of aethalometersJ Aerosol Sci3414451463CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • L. Gomes
    • 1
  • M. Mallet
    • 2
  • J. C. Roger
    • 3
  • P. Dubuisson
    • 4
  1. 1.Météo France, Centre National de Recherches MétéorologiquesToulouseFrance
  2. 2.Laboratoire d’AérologieUniversité Paul Sabatier/CNRSToulouseFrance
  3. 3.Laboratoire de Météorologie PhysiqueUniversité Blaise PascalClermont-FerrandFrance
  4. 4.Ecosystèmes Littoraux et CôtiersUniversité des Sciences et TechnologiesLilleFrance

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