GMD Geoscientific Model Development GMD 1991-9603 Copernicus GmbH Göttingen, Germany 10.5194/gmd-3-391-2010 Description and evaluation of GMXe: a new aerosol submodel for global simulations (v1) Pringle K. J. 1 2 Tost H. 1 Message S. 1 Steil B. 1 Giannadaki D. 1 Nenes A. 3 Fountoukis C. 4 Stier P. 5 Vignati E. 6 Lelieveld J. 1 7 Max Planck Institute for Chemistry, Mainz, Germany School of Earth and Environment, University of Leeds, Leeds, UK Schools of Earth & Atmospheric Sciences and Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, USA Institute of Chemical Engineering and High Temperature Chemical Processes, Foundation for Research and Technology – Hellas, Patras, Greece Atmospheric, Oceanic and Planetary Physics, Department of Physics, University of Oxford, Oxford, UK Joint Research Centre, Institute for Environment and Sustainability, Climate Change Unit, Ispra, Italy The Cyprus Institute, Energy, Environment and Water Research Centre, Nicosia, Cyprus 10 09 2010 3 2 391 412 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.geosci-model-dev.net/3/391/2010/gmd-3-391-2010.html The full text article is available as a PDF file from http://www.geosci-model-dev.net/3/391/2010/gmd-3-391-2010.pdf

We present a new aerosol microphysics and gas aerosol partitioning submodel (Global Modal-aerosol eXtension, GMXe) implemented within the ECHAM/MESSy Atmospheric Chemistry model (EMAC, version 1.8). The submodel is computationally efficient and is suitable for medium to long term simulations with global and regional models. The aerosol size distribution is treated using 7 log-normal modes and has the same microphysical core as the M7 submodel (Vignati et al., 2004). <br><br> The main developments in this work are: (i) the extension of the aerosol emission routines and the M7 microphysics, so that an increased (and variable) number of aerosol species can be treated (new species include sodium and chloride, and potentially magnesium, calcium, and potassium), (ii) the coupling of the aerosol microphysics to a choice of treatments of gas/aerosol partitioning to allow the treatment of semi-volatile aerosol, and, (iii) the implementation and evaluation of the developed submodel within the EMAC model of atmospheric chemistry. <br><br> Simulated concentrations of black carbon, particulate organic matter, dust, sea spray, sulfate and ammonium aerosol are shown to be in good agreement with observations (for all species at least 40% of modeled values are within a factor of 2 of the observations). The distribution of nitrate aerosol is compared to observations in both clean and polluted regions. Concentrations in polluted continental regions are simulated quite well, but there is a general tendency to overestimate nitrate, particularly in coastal regions (geometric mean of modelled values/geometric mean of observed data ≈2). In all regions considered more than 40% of nitrate concentrations are within a factor of two of the observations. Marine nitrate concentrations are well captured with 96% of modeled values within a factor of 2 of the observations.

 References 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, 13791–13824, doi:10.1029/1999JD900083, 1999. Adams, P J., Seinfeld, J H., Koch, D M., Mickley, L J., and Jacob, D J.: General circulation model assessment of direct radiative forcing by the sulfate-nitrate-ammonium-water inorganic aerosol system, J. Geophys. Res.-Atmos., 106, 1097–1111, 2001. Ames, R B. and Malm, W C.: Comparison of sulfate and nitrate particle mass concentrations measured by IMPROVE and the CDN, Atmos. Environ., 35, 905–916, 2001. Andreae, M. O.: Correlation between cloud condensation nuclei concentration and aerosol optical thickness in remote and polluted regions, Atmos. Chem. Phys., 9, 543–556, doi:10.5194/acp-9-543-2009, 2009. Bauer, S E. and Koch, D.: Impact of heterogeneous sulfate formation at mineral dust surfaces on aerosol loads and radiative forcing in the Goddard Institute for Space Studies general circulation model, J. Geophys. Res.-Atmos., 110, D17202, doi:10.1029/2005JD005870, 2005. Bauer, S E., Koch, D., Unger, N., Metzger, S M., Shindell, D T., and Streets, D G.: Nitrate aerosols today and in 2030: a global simulation including aerosols and tropospheric ozone, J. Geophys. Res.-Atmos., 7, 5043–5059, 2007. Capaldo, K., Pilinis, C., and Pandis, S N.: A computationally efficient hybrid approach for dynamic gas/aerosol transfer in air quality models, Atmos. Environ., 34, 3617–3627, 2000. Castro, P. and Huber, M E.: Marine Biology, McGraw-Hill, 2003. Clarisse, L., Clerbaux, C., Dentener, F Hurtmans, D., and Coheur, P.-F.: Global ammonia distribution derived from infrared satellite observations, Nat. Geosci., 2, 479–483, 2009. Dentener, F., Kinne, S., Bond, T., Boucher, O., Cofala, J., Generoso, S., Ginoux, P., Gong, S., Hoelzemann, J. J., Ito, A., Marelli, L., Penner, J. E., Putaud, J.-P., Textor, C., Schulz, M., van der Werf, G. R., and Wilson, J.: Emissions of primary aerosol and precursor gases in the years 2000 and 1750 prescribed data-sets for AeroCom, Atmos. Chem. Phys., 6, 4321–4344, doi:10.5194/acp-6-4321-2006, 2006. Derwent, R., Collins, W., Jenkin, M., Johnson, C., and Stevenson, D.: The Global Distribution of Secondary Particulate Matter in a 3-D Lagrangian Chemistry Transport Model, J. Atmos. Chem., 44, 57–95, 2003. Feng, Y. and Penner, Y.: Global modeling of nitrate and ammonium: Interaction of aerosols and tropospheric chemistry, J. Geophys. Res.-Atmos., 112, doi:10.1029/2005JD006404, 2007. Forster, P., Ramaswamy, V., Artaxo, P., Berntsen, T., Betts, R., Fahey, D., Haywood, J., Lean, J., Lowe, D., Myhre, G., Nganga, J., Prinn, R., Raga, G., M., S., and Dorland, R V.: Integovernmental Panel on Climate Change, chap. Changes in Atmospheric Constituents and in Radiative Forcing, Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 2007. Fountoukis, C. and Nenes, A.: ISORROPIA II: a computationally efficient thermodynamic equilibrium model for K$^+$ - Ca$^2+$ - Mg$^2+$ - NH$_4^+$ - Na$^+$ - SO$_4^2-$ - NO$_3^-$ - Cl$^-$-H<sub>2</sub>O aerosols, Atmos. Chem. Phys., 7, 4639-4659, doi:10.5194/acp-7-4639-2007, 2007. Fountoukis, C., Nenes, A., Sullivan, A., Weber, R., Van Reken, T., Fischer, M., Matías, E., Moya, M., Farmer, D., and Cohen, R. C.: Thermodynamic characterization of Mexico City aerosol during MILAGRO 2006, Atmos. Chem. Phys., 9, 2141–2156, doi:10.5194/acp-9-2141-2009, 2009. Fuchs, N.: Evaporation and droplet growth in gaseous media, Pergamon Press, 1959. Fuchs, N.: The Mechanics of aerosols, Pergamon Press, 1964. Ganzeveld, L. and Lelieveld, J.: Dry deposition parametrization in a chemistry general circulation model and its influence on the distribution of reactive trace gases, J. Geophys. Res.-Atmos., 100, 20999–21012, 1995. Ganzeveld, L., Lelieveld, J., and Roelofs, G.: A dry deposition parameterization for sulfur oxides in a chemistry and general circulation model, J. Geophys. Res.-Atmos., 103, 5679–5694, doi:10.1029/97JD03077, 1998. Gerber, H E.: Supersaturation and Droplet Sectral Evolution in Fog, J. Atmos. Sci., 48, 2569-2588, 1991. Ginoux, P., Chin, M., Tegen, I., Prospero, J M., Holben, B N., Dubovik, O., and Lin, S J.: Sources and distribution of dust aerosols with the GOCART model, J. Geophys. Res.-Atmos., 106, 20255–20273, 2001. Ginoux, P., Prospero, J M., Torres, O., and Chin, M.: Long-term simulation of global dust distribution with the GOCART model: Correlation with the North Atlantic Oscillation, Environ. Modell. Softw., 19, 113–128, doi:10.1016/S1364-8152(03)00114-2, 2003. Gong, S.: A parameterization of sea-salt aerosol source function for sub- and super-micron particles, Global Biogeochem. Cy., 17, 1097–1103, 2003. Granat, L., Engström, J E., Praveen, S., and Rodhe, H.: Light absorbing material (soot) in rainwater and in aerosol particles in the Maldives, J. Geophys. Res.-Atmos., 115, D16307, doi:10.1029/2009JD013768, 2010. Han, K. M., Song, C. H., Ahn, H. J., Park, R. S., Woo, J. H., Lee, C. K., Richter, A., Burrows, J. P., Kim, J. Y., and Hong, J. H.: Investigation of NO<sub>x</sub> emissions and NO<sub>x</sub>-related chemistry in East Asia using CMAQ-predicted and GOME-derived NO2 columns, Atmos. Chem. Phys., 9, 1017–1036, doi:10.5194/acp-9-1017-2009, 2009. Hanisch, F. and Crowley, J N.: Heterogeneous reactivity of NO and HNO3 on mineral dust in the presence of ozone, Phys. Chem. Chem. Phys., 5, 883–887, doi:10.1039/B211503D, 2003. Hofmeister, F.: Zur Lehre von der Wirkung der Salze, Arch. Exp. Pathol. Pharmakol, (Leipzig) 24 (1888) 247-260; translated in: Zur Lehre von der Wirkung der Salze (about the science of the effect of salts: Franz Hofmeisters historical papers, Curr. Opin. Coll. Interface (2004), 19–37, 1888. Holben, B N., Tanré, D., Smirnov, A., Eck, T F., Slutsker, I., Abuhassan, N., Newcomb, W W., Schafer, J S., Chatenet, B., Lavenu, F., Kaufman, Y J., Castle, J V., Setzer, A., Markham, B., Clark, D., Frouin, R., Halthore, R., Karneli, A., O'Neill, N T., Pietras, C., Pinker, R T., Voss, K., and Zibordi, G.: An emerging ground-based aerosol climatology: Aerosol optical depth from AERONET, J. Geophys. Res.-Atmos., 106, 12067–12098, doi:10.1029/2001JD900014, 2001. Jacobson, M.: Studying the effects of calcium and magnesium on size-distributed nitrate and ammonium with EQUISOLV II, Atmos. Environ., 33, 3635–3649, 1999. Jeuken, A., Veefkind, J P., Dentener, F., Metzger, S., and Gonzalez, C R.: Simulation of the aerosol optical depth over Europe for August 1997 and a comparison with observations, J. Geophys. Res.-Atmos., 106, 28295–28311, 2001. Jöckel, P., Sander, R., Kerkweg, A., Tost, H., and Lelieveld, J.: Technical Note: The Modular Earth Submodel System (MESSy) – a new approach towards Earth System Modeling, Atmos. Chem. Phys., 5, 433–444, doi:10.5194/acp-5-433-2005, 2005. Jöckel, P., Tost, H., Pozzer, A., Brühl, C., Buchholz, J., Ganzeveld, L., Hoor, P., Kerkweg, A., Lawrence, M. G., Sander, R., Steil, B., Stiller, G., Tanarhte, M., Taraborrelli, D., van Aardenne, J., and Lelieveld, J.: The atmospheric chemistry general circulation model ECHAM5/MESSy1: consistent simulation of ozone from the surface to the mesosphere, Atmos. Chem. Phys., 6, 5067–5104, doi:10.5194/acp-6-5067-2006, 2006. Karydis, V A., Tsimpidi, A P., Fountoukis, C., Nenes, A., Zavala, M., Lei, W., Molina, L T., and Pandis, S N.: Simulating the fine and coarse inorganic particulate matter concentrations in a polluted megacity, Atmos. Environ., 44, 608–620, doi:10.1016/j.atmosenv.2009.11.023, 2010. Kerkweg, A., Buchholz, J., Ganzeveld, L., Pozzer, A., Tost, H., and Jöckel, P.: Technical Note: An implementation of the dry removal processes DRY DEPosition and SEDImentation in the Modular Earth Submodel System (MESSy), Atmos. Chem. Phys., 6, 4617–4632, doi:10.5194/acp-6-4617-2006, 2006a. Kerkweg, A., Sander, R., Tost, H., and Jöckel, P.: Technical note: Implementation of prescribed (OFFLEM), calculated (ONLEM), and pseudo-emissions (TNUDGE) of chemical species in the Modular Earth Submodel System (MESSy), Atmos. Chem. Phys., 6, 3603–3609, doi:10.5194/acp-6-3603-2006, 2006b. Kerkweg, A., Sander, R., Tost, H., Jöckel, P., and Lelieveld, J.: Technical Note: Simulation of detailed aerosol chemistry on the global scale using MECCA-AERO, Atmos. Chem. Phys., 7, 2973–2985, doi:10.5194/acp-7-2973-2007, 2007. Kiehl, J. and Briegleb, B P.: The relative roles of sulfate aerosols and greenhouse gases in climate forcing, Science, 260, 311–314, 1993. Kinne, S., Schulz, M., Textor, C., Guibert, S., Balkanski, Y., Bauer, S. E., Berntsen, T., Berglen, T. F., Boucher, O., Chin, M., Collins, W., Dentener, F., Diehl, T., Easter, R., Feichter, J., Fillmore, D., Ghan, S., Ginoux, P., Gong, S., Grini, A., Hendricks, J., Herzog, M., Horowitz, L., Isaksen, I., Iversen, T., Kirkevåg, A., Kloster, S., Koch, D., Kristjansson, J. E., Krol, M., Lauer, A., Lamarque, J. F., Lesins, G., Liu, X., Lohmann, U., Montanaro, V., Myhre, G., Penner, J., Pitari, G., Reddy, S., Seland, O., Stier, P., Takemura, T., and Tie, X.: An AeroCom initial assessment - optical properties in aerosol component modules of global models, Atmos. Chem. Phys., 6, 1815–1834, doi:10.5194/acp-6-1815-2006, 2006. Konovalov, I. B., Beekmann, M., Burrows, J. P., and Richter, A.: Satellite measurement based estimates of decadal changes in European nitrogen oxides emissions, Atmos. Chem. Phys., 8, 2623–2641, doi:10.5194/acp-8-2623-2008, 2008. Kulmala, M., Laaksonen, A., and Pirjola, L.: Parameterization for sulfuric acid/water nucleation rates, J. Geophys. Res.-Atmos., 103, 8301–8307, 1998. Lauer, A. and Hendricks, J.: Simulating aerosol microphysics with the ECHAM4/MADE GCM - Part II: Results from a first multiannual simulation of the submicrometer aerosol, Atmos. Chem. Phys., 6, 5495–5513, doi:10.5194/acp-6-5495-2006, 2006. Lauer, A., Hendricks, J., Ackermann, I., Schell, B., Hass, H., and Metzger, S.: Simulating aerosol microphysics with the ECHAM/MADE GCM - Part I: Model description and comparison with observations, Atmos. Chem. Phys., 5, 3251–3276, doi:10.5194/acp-5-3251-2005, 2005. Liao, H., Adams, P J., Chung, S H., Seinfeld, J H., Mickley, L J., and Jacob, D J.: Interactions between tropospheric chemistry and aerosols in a unified general circulation model, J. Geophys. Res.-Atmos., 108(D1), 4001, doi:10.1029/2001JD001260, 2003. Liousse, C., Penner, J E., Chuang, C., Walton, J J., Eddleman, H., and Cachier, H.: A global three-dimensional model study of carbonaceous aerosols, J. Geophys. Res.-Atmos., 101(D14), 19411–19432, doi:10.1029/95JD03426, 1996. Lohmann, U., Stier, P., Hoose, C., Ferrachat, S., Kloster, S., Roeckner, E., and Zhang, J.: Cloud microphysics and aerosol indirect effects in the global climate model ECHAM5-HAM, Atmos. Chem. Phys., 7, 3425–3446, doi:10.5194/acp-7-3425-2007, 2007. 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, D03306, doi:10.1029/2003JD003739, 2004. Mann, G. W., Carslaw, K. S., Spracklen, D. V., Ridley, D. A., Manktelow, P. T., Chipperfield, M. P., Pickering, S. J., and Johnson, C. E.: Description and evaluation of GLOMAP-mode: a modal global aerosol microphysics model for the UKCA composition-climate model, Geosci. Model Dev. Discuss., 3, 651–734, doi:10.5194/gmdd-3-651-2010, 2010. Meng, Z. and Seinfeld, J.: Time scales to achieve atmospheric gas-aerosol equilibrium for volatile species, Atmos. Environ., 30, 2889–2900, 1996. Metzger, S. and Lelieveld, J.: Reformulating atmospheric aerosol thermodynamics and hygroscopic growth into fog, haze and clouds, Atmos. Chem. Phys., 7, 3163–3193, doi:10.5194/acp-7-3163-2007, 2007. 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, 2002. 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, doi:10.5194/acp-6-2549-2006, 2006. Myhre, G., Grini, A., and Metzger, S.: Modelling of nitrate and ammonium-containing aerosols in presence of sea salt, Atmos. Chem. Phys., 6, 4809–4821, doi:10.5194/acp-6-4809-2006, 2006. Nenes, A., Pandis, S N., and Pilinis, C.: ISORROPIA: A new thermodynamic equilibrium model for multiphase multicomponent inorganic aerosols, Aquat. Geochem., 4, 123–152, 1998a. Nenes, A., Pandis, S N., and Pilinis, C.: Continued Development and Testing of a New Thermodynamic Aerosol Module for Urban and Regional Air Quality Models, Atmos. Environ., 33, 1553–1560, 1998b. Pakkanen, T A.: Study of formation of coarse particle nitrate aerosol, Atmos. Environ., 30, 2475–2482, doi:10.1016/1352-2310(95)00492-0, 1996. Pye, H. O T., Liao, H., Wu, S., Mickley, L J., Jacob, D J., Henze, D K., and Seinfeld, J H.: Effect of changes in climate and emissions on future sulfate-nitrate-ammonium aerosol levels in the United States, J. Geophys. Res.-Atmos., 114, D01205+, doi:10.1029/2008JD010701, 2009. Rodriguez, M A. and Dabdub, D.: IMAGES-SCAPE2: A modeling study of size- and chemically resolved aerosol thermodynamics in a global chemical transport model, J. Geophys. Res., 109, D02203, doi:10.1029/2003JD003639, 2004. Roeckner, E., Brokopf, R., Esch, M., Giorgetta, M., Hagemann, S., Kornblueh, L., Manzini, E., Schlese, U., and Schulzweida, U.: Sensitivity of simulated climate to horizontal and vertical resolution in the ECHAM5 atmosphere model, J. Climate, 19, 3371–3791, doi:10.1175/JCLI3824.1, 2006. Sander, R., Kerkweg, A., Jöckel, P., and Lelieveld, J.: Technical note: The new comprehensive atmospheric chemistry module MECCA, Atmos. Chem. Phys., 5, 445–450, doi:10.5194/acp-5-445-2005, 2005. Stier, P., Feichter, J., Kinne, S., Kloster, S., Vignati, E., Wilson, J., Ganzeveld, L., Tegen, I., Werner, M., Balkanski, Y., Schulz, M., Boucher, O., Minikin, A., and Petzold, A.: The aerosol-climate model ECHAM5-HAM, Atmos. Chem. Phys., 5, 1125–1156, doi:10.5194/acp-5-1125-2005, 2005. Stier, P., Feichter, J., Roeckner, E., Kloster, S., and Esch, M.: The evolution of the global aerosol system in a transient climate simulation from 1860 to 2100, Atmos. Chem. Phys., 6, 3059–3076, doi:10.5194/acp-6-3059-2006, 2006. Textor, C., Schulz, M., Guibert, S., Kinne, S., Balkanski, Y., Bauer, S., Berntsen, T., Berglen, T., Boucher, O., Chin, M., Dentener, F., Diehl, T., Easter, R., Feichter, H., Fillmore, D., Ghan, S., Ginoux, P., Gong, S., Grini, A., Hendricks, J., Horowitz, L., Huang, P., Isaksen, I., Iversen, I., Kloster, S., Koch, D., Kirkevåg, A., Kristjansson, J. E., Krol, M., Lauer, A., Lamarque, J. F., Liu, X., Montanaro, V., Myhre, G., Penner, J., Pitari, G., Reddy, S., Seland, Ø., Stier, P., Takemura, T., and Tie, X.: Analysis and quantification of the diversities of aerosol life cycles within AeroCom, Atmos. Chem. Phys., 6, 1777–1813, doi:10.5194/acp-6-1777-2006, 2006. Textor, C., Schulz, M., Guibert, S., Kinne, S., Balkanski, Y., Bauer, S., Berntsen, T., Berglen, T., Boucher, O., Chin, M., Dentener, F., Diehl, T., Feichter, J., Fillmore, D., Ginoux, P., Gong, S., Grini, A., Hendricks, J., Horowitz, L., Huang, P., Isaksen, I. S. A., Iversen, T., Kloster, S., Koch, D., Kirkevåg, A., Kristjansson, J. E., Krol, M., Lauer, A., Lamarque, J. F., Liu, X., Montanaro, V., Myhre, G., Penner, J. E., Pitari, G., Reddy, M. S., Seland, Ø., Stier, P., Takemura, T., and Tie, X.: The effect of harmonized emissions on aerosol properties in global models - an AeroCom experiment, Atmos. Chem. Phys., 7, 4489–4501, doi:10.5194/acp-7-4489-2007, 2007. Tost, H., Jöckel, P., Kerkweg, A., Sander, R., and Lelieveld, J.: Technical note: A new comprehensive SCAVenging submodel for global atmospheric chemistry modelling, Atmos. Chem. Phys., 6, 565–574, doi:10.5194/acp-6-565-2006, 2006a. Tost, H., Jöckel, P., and Lelieveld, J.: Influence of different convection parameterisations in a GCM, Atmos. Chem. Phys., 6, 5475–5493, doi:10.5194/acp-6-5475-2006, 2006b. Tost, H., Jöckel, P., Kerkweg, A., Pozzer, A., Sander, R., and Lelieveld, J.: Global cloud and precipitation chemistry and wet deposition: tropospheric model simulations with ECHAM5/MESSy1, Atmos. Chem. Phys., 7, 2733–2757, doi:10.5194/acp-7-2733-2007, 2007a. Tost, H., Jöckel, P., and Lelieveld, J.: Lightning and convection parameterisations - uncertainties in global modelling, Atmos. Chem. Phys., 7, 4553–4568, doi:10.5194/acp-7-4553-2007, 2007b. Tost, H., Lawrence, M. G., Brühl, C., Jöckel, P., The GABRIEL Team, and The SCOUT-O3-DARWIN/ACTIVE Team: Uncertainties in atmospheric chemistry modelling due to convection parameterisations and subsequent scavenging, Atmos. Chem. Phys., 10, 1931–1951, doi:10.5194/acp-10-1931-2010, 2010. Tsigaridis, K., Lathière, J., Kanakidou, M., and Hauglustaine, D. A.: Naturally driven variability in the global secondary organic aerosol over a decade, Atmos. Chem. Phys., 5, 1891–1904, doi:10.5194/acp-5-1891-2005, 2005. Tsigaridis, K., Krol, M., Dentener, F. J., Balkanski, Y., Lathière, J., Metzger, S., Hauglustaine, D. A., and Kanakidou, M.: Change in global aerosol composition since preindustrial times, Atmos. Chem. Phys., 6, 5143–5162, doi:10.5194/acp-6-5143-2006, 2006. Vandoren, J M., Watson, L R., Davidovits, P., Worsnop, D R., Zahniser, M S., and Kolb, C E.: Temperature dependence of the uptake coefficients of nitric acid, hydrochloric acid and nitrogen oxide (N2O5) by water droplets, J. Phys. Chem., 94, p 3265, 1990. Veefkind, P.: Aerosol satellite remote sensing, Utrecht University, 1999. Vehkamaki, H., Kulmala, M., Napari, I., Lehtinen, K., Timmreck, C., Noppel, M., and Laaksonen, A.: An improved parametrisation for sulfuric acid-water nucleation rates for tropospheric and stratospheric conditions, J. Geophys. Res.-Atmos., 107(D22), 4622, doi:10.1029/2002JD002184, 2002. Vignati, E., Wilson, J., and Stier, P.: M7: An efficient size-resolved aerosol microphysics module for large-scale aerosol transport models, J. Geophys. Res., 109, D22202, doi:10.1029/2003JD004485, 2004. Wexler, A. and Seinfeld, J H.: Analysis of aerosol ammonium nitrate: Departures from equilibrium during SCAQS, Atmos. Environ., 26A, 579–591, 1992. Wilson, J., Cuvelier, C., and Raes, F.: A modeling study of global mixed aerosol fields, J. Geophys. Res.-Atmos., 106(D24), 34081–34108, doi:2000JD000198, 2000. Yeatman, S G., Spokes, L J., and Jickells, T D.: Comparisons of coarse-mode aerosol nitrate and ammonium at two polluted coastal sites, Atmos. Environ., 35, 1321–1335, doi:10.1016/S1352-2310(00)00452-0, 2001. Yu, S., Dennis, R., Roselle, S., Nenes, A., Walker, J., Eder, B., Schere, K., Swall, J., and Robarge, W.: An assessment of the ability of three-dimensional air quality models with current thermodynamic equilibrium models to predict aerosol NO$_3^-$, J. Geophys. Res.-Atmos., 110, D07S13, doi:10.1029/2004JD004718, 2005. Zhang, Q., Jimenez, J L., Canagaratna, M R., Allan, J D., Coe, H., Ulbrich, I., Alfarra, M R., Takami, A., Middlebrook, A M., Sun, Y L., Dzepina, K., Dunlea, E., Docherty, K., DeCarlo, P F., Salcedo, D., Onasch, T., Jayne, J T., Miyoshi, T., Shimono, A., Hatakeyama, S., Takegawa, N., Kondo, Y., Schneider, J., Drewnick, F., Borrmann, S., Weimer, S., Demerjian, K., Williams, P., Bower, K., Bahreini, R., Cottrell, L., Griffin, R J., Rautiainen, J., Sun, J Y., Zhang, Y M., and Worsnop, D R.: Ubiquity and dominance of oxygenated species in organic aerosols in anthropogenically-influenced Northern Hemisphere midlatitudes, Geophys. Res. Lett., 34, L13801+, doi:10.1029/2007GL029979, 2007. Zhuang, H., Chan, C K., Fang, M., and Wexler, A S.: Formation of nitrate and non-sea-salt sulfate on coarse particles, Atmos. Environ., 33, 4223–4233, doi:10.1016/S1352-2310(99)00186-7, 1999.