ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-6-4809-2006 Modelling of nitrate and ammonium-containing aerosols in presence of sea salt Myhre G. 1 2 Grini A. 1 Metzger S. 3 Department of Geosciences, University of Oslo, Oslo, Norway Center for International Climate and Environmental Research-Oslo, Oslo, Norway Max-Planck-Institute for Chemistry, Department of Atmospheric Chemistry, Mainz, Germany 25 10 2006 6 12 4809 4821 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/6/4809/2006/acp-6-4809-2006.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/6/4809/2006/acp-6-4809-2006.pdf

A thermodynamical model for treatment of gas/aerosol partitioning of semi volatile inorganic aerosols has been implemented in a global chemistry and aerosol transport model (Oslo CTM2). The sulphur cycle and sea salt particles have been implemented earlier in the Oslo CTM2 and the focus of this study is on nitrate partitioning to the aerosol phase and if particulate nitrate is expected to form in fine or coarse mode aerosols. Modelling of the formation of fine mode nitrate particles is complicated since it depends on other aerosol components and aerosol precursors as well as meteorological condition. The surface concentrations from the model are compared to observed surface concentrations at around 20 sites around Europe for nitrate and ammonium. The agreement for nitrate is good but the modelled values are somewhat underestimated compared to observations at high concentrations, whereas for ammonium the agreement is very good. However, we underscore that such a comparison is not of large importance for the aerosol optical depth of particulate nitrate since the vertical profile of aerosol components and their precursors are so important. Fine mode nitrate formation depends on vertical profiles of both ammonia/ammonium and sulphate. The model results show that fine mode particulate nitrate play a non-negligible role in the total aerosol composition in certain industrialized regions and therefore have a significant local radiative forcing. On a global scale the aerosol optical depth of fine mode nitrate is relatively small due to limited availability of ammonia and loss to larger sea salt particles. Inclusion of sea salt in the calculations reduces the aerosol optical depth and burden of fine mode nitrate by 25% on a global scale but with large regional variations.

 References Adams, P. J. and Seinfeld, J. H.: Predicting global aerosol size distributions in general circulation models, J. Geophys. Res.-Atmos., 107(D19), 4370, doi:10.129/2001JD00101, 2002. Adams, P. J., Seinfeld, J. H., Koch, D., Mickley, L., and Jacob, D.: General circulation model assessment of direct radiative forcing by the sulfate-nitrate-ammonium-water inorganic aerosol system, J. Geophys. Res.-Atmos., 106(D1), 1097–1111, 2001. Adams, P. J., Seinfeld, J. H., and Koch, D. M.: Global concentrations of tropospheric sulfate, nitrate, and ammonium aerosol simulated in a general circulation model, J. Geophys. Res.-Atmos., 104(D11), 13 791–13 823, 1999. Berglen, T. F., Berntsen, T. K., Isaksen, I. S. A., and Sundet, J. K.: A global model of the coupled sulfur/oxidant chemistry in the troposphere: The sulfur cycle, J. Geophys. Res.-Atmos., 109(D19), D19310, doi:10.1029/2003JD003948, 2004. Berntsen, T. K. and Isaksen, I. S. A.: A global three-dimensional chemical transport model for the troposphere.1. Model description and CO and ozone results, J. Geophys. Res.-Atmos., 102(D17), 21 239–21 280, 1997. Bouwman, A. F., Lee, D. S., Asman, W. A. H., Dentener, F. J., VanderHoek, K. W., et al.: A global high-resolution emission inventory for ammonia, Global Biogeochem. Cycles, 11(4), 561–587, 1997. Capaldo, K. P., Pilinis, C., and Pandis, S. N.: A computationally efficient hybrid approach for dynamic gas/aerosol transfer in air quality models, Atmos. Environ., 34(21), 3617–3627, 2000. Derwent, R. G., Jenkin, M. E., Johnson, C. E., and Stevenson, D. S.: The global distribution of secondary particulate matter in a 3-D Lagrangian chemistry transport model, J. Atmos. Chem., 44, 57–95, 2003. Evans, C. D., Cullen, J. M., Alewell, C., Kopacek, J., Marchetto, A., et al.: Recovery from acidification in European surface waters, Hydrol. Earth Syst. Sci., 5, 283–297, 2001. Fitzgerald, J. W.: Approximation Formulas For Equilibrium Size Of An Aerosol Particle As A Function Of Its Dry Size And Composition And Ambient Relative Humidity, J. Appl. Meteorol., 14(6), 1044–1049, 1975. Grini, A., Myhre, G., Sundet, J. K., and Isaksen, I. S. A.: Modeling the annual cycle of sea salt in the global 3D model Oslo CTM2: Concentrations, fluxes, and radiative impact, J. Climate, 15(13), 1717–1730, 2002. Holtslag, A. A. M., Debruijn, E. I. F., and Pan, H. L.: A High-Resolution Air-Mass Transformation Model For Short-Range Weather Forecasting, Mon. Wea. Rev., 118(8), 1561–1575, 1990. Hueglin, C., Gehrig, R., Baltensperger, U., Gysel, M., Monn, C., et al.: Chemical characterisation of PM2.5, PM10 and coarse particles at urban, near-city and rural sites in Switzerland, Atmos. Environ., 39(4), 637–651, 2005. Jacobson, M. Z.: Global direct radiative forcing due to multicomponent anthropogenic and natural aerosols, J. Geophys. Res.-Atmos., 106(D2), 1551–1568, 2001. Jaffe, D., Tamura, S., and Harris, J.: Seasonal cycle and composition of background fine particles along the west coast of the US, Atmos. Environ., 39(2), 297–306, 2005. Kinne, S., Schulz, M., Textor, C., Guibert, S., Balkanski, Y., et al.: An AeroCom initial assessment - optical properties in aerosol component modules of global models, Atmos. Chem. Phys., 6, 1815–1834, 2006. Lefer, B. L. and Talbot, R. W.: Summertime measurements of aerosol nitrate and ammonium at a northeastern US site, J. Geophys. Res.-Atmos., 106(D17), 20 365–20 378, 2001. Lelieveld, J., Berresheim, H., Borrmann, S., Crutzen, P. J., Dentener, F. J., et al.: Global air pollution crossroads over the Mediterranean, Science, 298(5594), 794–799, 2002. Liao, H. and Seinfeld, J. H.: Global impacts of gas-phase chemistry-aerosol interactions on direct radiative forcing by anthropogenic aerosols and ozone, J. Geophys. Res., 110, D18208, doi:10.1029/2005JD005907, 2005. Liao, H., Seinfeld, J. H., Adams, P. J., and Mickley, L. J.: Global radiative forcing of coupled tropospheric ozone and aerosols in a unified general circulation model, J. Geophys. Res.-Atmos., 109(D16), D16207, doi:10.1029/2003JD004456, 2004. Lide, D. R.: CRC handbook of chemistry and physics, A ready-reference book of chemical and physical data, 72nd ed., 1991. Malm, W. C., Schichtel, B. A., Pitchford, M. L., Ashbaugh, L. L., and Eldred, R. A.: Spatial and monthly trends in speciated fine particle concentration in the United States, J. Geophys. Res.-Atmos., 109(D3), D03306, doi:10.1029/2003/JD003739, 2004. Marinoni, A., Laj, P., Deveau, P. A., Marino, F., Ghermandi, G., et al.: Physicochemical properties of fine aerosols at Plan d'Aups during ESCOMPTE, Atmos. Res., 74(1–4), 565–580, 2005. Martin, S. T., Hung, H. M., Park, R. J., Jacob, D. J., Spurr, R. J. D., et al.: Effects of the physical state of tropospheric ammonium-sulfate-nitrate particles on global aerosol direct radiative forcing, Atmos. Chem. Phys., 4, 183–214, 2004. Meng, Z. Y. and Seinfeld, J. H.: Time scales to achieve atmospheric gas-aerosol equilibrium for volatile species, Atmos. Environ., 30(16), 2889–2900, 1996. Metzger, S., Dentener, F., Krol, M., Jeuken, A., and Lelieveld, J.: Gas/aerosol partitioning – 2. Global modeling results, J. Geophys. Res.-Atmos., 107(D16), 4313, doi:10.1029/2001JD001103, 2002a. Metzger, S., Dentener, F., Pandis, S., and Lelieveld, J.: Gas/aerosol partitioning: 1. A computationally efficient model, J. Geophys. Res.-Atmos., 107(D16), 4312, doi:10.1029/2001JD001102, 2002b. Metzger, S., Mihalopoulos, N., and Lelieveld, J.: Importance of mineral cations and organics in gas-aerosol partitioning of reactive nitrogen compounds: case study based on MINOS results, Atmos. Chem. Phys., 6, 2549–2567, 2006. Metzger, S. M.: Gas/Aerosol Partitioning: A simplified Method for Global Modeling, University Utrecht, The Netherlands, 2000. Myhre, G., Jonson, J. E., Bartnicki, J., Stordal, F., and Shine, K. P.: Role of spatial and temporal variations in the computation of radiative forcing due to sulphate aerosols: A regional study, Quart. J. Roy. Meteorol. Soc., 128(581), 973–989, 2002. Myhre, G., Stordal, F., Berglen, T. F., Sundet, J. K., and Isaksen, I. S. A.: Uncertainties in the radiative forcing due to sulfate aerosols, J. Atmos. Sci., 61(5), 485–498, 2004. Nenes, A., Pandis, S. N., and Pilinis, C.: ISORROPIA: A new thermodynamic equilibrium model for multiphase multicomponent inorganic aerosols, Aquatic Geochemistry, 4(1), 123–152, 1998. Novakov, T., Hegg, D. A., and Hobbs, P. V.: Airborne measurements of carbonaceous aerosols on the East Coast of the United States, J. Geophys. Res.-Atmos., 102(D25), 30 023–30 030, 1997. Park, M. H., Kim, Y. P., Kang, C. H. and Shim, S. G.: Aerosol composition change between 1992 and 2002 at Gosan, Korea, J. Geophys. Res.-Atmos., 109(D19), D19S13, doi:10.1029/2003JD00411, 2004. Pilinis, C., Capaldo, K. P., Nenes, A., and Pandis, S. N.: MADM – A new multicomponent aerosol dynamics model, Aerosol Sci. Technol., 32(5), 482–502, 2000. Prather, M. J.: Numerical Advection By Conservation Of 2nd-Order Moments, J. Geophys. Res.-Atmos., 91(D6), 6671–6681, 1986. Putaud, J. P., Raes, F., Van Dingenen, R., Bruggemann, E., Facchini, M. C., et al.: European aerosol phenomenology-2: chemical characteristics of particulate matter at kerbside, urban, rural and background sites in Europe, Atmos. Environ., 38(16), 2579–2595, 2004. Quinn, P. K. and Bates, T. S.: Regional aerosol properties: Comparisons of boundary layer measurements from ACE 1, ACE 2, aerosols99, INDOEX, ACE asia, TARFOX, and NEAQS, J. Geophys. Res.-Atmos., 110(D14), D14202, doi:10.1029/2004JD004755, 2005. Ramanathan, V., Crutzen, P. J., Lelieveld, J., Mitra, A. P., Althausen, D., et al.: Indian Ocean Experiment: An integrated analysis of the climate forcing and effects of the great Indo-Asian haze, J. Geophys. Res.-Atmos., 106(D22), 28 371–28 398, 2001. Sievering, H., Boatman, J., Gorman, E., Kim, Y., Anderson, L., et al.: Removal Of Sulfur From The Marine Boundary-Layer By Ozone Oxidation In Sea-Salt Aerosols, Nature, 360(6404), 571–573, 1992. Sopauskiene, D., Jasineviciene, D., and Stapcinskaite, S.: The effect of changes in European anthropogenic emissions on the concentrations of sulphur and nitrogen components in air and precipitation in Lithuania, Water Air and Soil Pollution, 130(1–4), 517–522, 2001. Sorteberg, A. and Hov, O.: Two parametrizations of the dry deposition exchange for SO2 and NH3 in a numerical model, Atmos. Environ., 30(10–11), 1823–1840, 1996. Stamnes, K., Tsay, S. C., Wiscombe, W., and Jayaweera, K.: Numerically Stable Algorithm For Discrete-Ordinate-Method Radiative-Transfer In Multiple-Scattering And Emitting Layered Media, Appl. Opt., 27(12), 2502–2509, 1988. Stoddard, J. L., Jeffries, D. S., Lukewille, A., Clair, T. A., Dillon, P. J., et al.: Regional trends in aquatic recovery from acidification in North America and Europe, Nature, 401(6753), 575–578, 1999. Textor, C., Schulz, M., Guibert, S., Kinne, S., Balkanski, Y., et al.: Analysis and quantification of the diversities of aerosol life cycles within AeroCom, Atmos. Chem. Phys., 6, 1777–1813, 2006. Tiedtke, M.: A Comprehensive Mass Flux Scheme For Cumulus Parameterization In Large-Scale Models, Mon. Wea. Rev., 117(8), 1779–1800, 1989. van Dorland, R., Dentener, F. J., and Lelieveld, J.: Radiative forcing due to tropospheric ozone and sulfate aerosols, J. Geophys. Res.-Atmos., 102(D23), 28 079–28 100, 1997. Wexler, A. S. and Seinfeld, J. H.: The Distribution Of Ammonium-Salts Among A Size And Composition Dispersed Aerosol, Atmos. Environ., 24(5), 1231–1246, 1990. Wolff, G. T.: On The Nature Of Nitrate In Coarse Continental Aerosols, Atmos. Environ., 18(5), 977–981, 1984.