ACP Atmospheric Chemistry and Physics ACP Atmos. Chem. Phys. 1680-7324 Copernicus Publications Göttingen, Germany 10.5194/acp-14-5127-2014 Evaluation of aerosol number concentrations in NorESM with improved nucleation parameterization Makkonen R. https://orcid.org/0000-0002-8961-3393 1 3 Seland Ø. 2 Kirkevåg A. https://orcid.org/0000-0002-3691-554X 2 Iversen T. https://orcid.org/0000-0001-6875-2979 1 2 Kristjánsson J. E. 1 Department of Geosciences, University of Oslo, P.O. Box 1047 Blindern, 0316 Oslo, Norway Norwegian Meteorological Institute, P.O. Box 43 Blindern, 0313 Oslo, Norway now at: Department of Physics, University of Helsinki, P.O. Box 64, 00014 Helsinki, Finland 26 05 2014 14 10 5127 5152 Copyright: © 2014 R. Makkonen et al. 2014 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://acp.copernicus.org/articles/14/5127/2014/acp-14-5127-2014.html The full text article is available as a PDF file from https://acp.copernicus.org/articles/14/5127/2014/acp-14-5127-2014.pdf

The Norwegian Earth System Model (NorESM) is evaluated against atmospheric observations of aerosol number concentrations. The model is extended to include an explicit mechanism for new particle formation and secondary organic aerosol (SOA) formation from biogenic precursors. Three nucleation mechanisms are included in NorESM: binary sulfuric acid, activation type, and organic nucleation. Ten model experiments are conducted to study the sensitivity of the simulated aerosol number concentrations to nucleation, SOA formation, black carbon size distribution and model meteorology. Simulated vertical profiles are evaluated against 12 flight campaigns. Comparison of monthly averaged aerosol number concentrations against 60 measurement sites reveals that the model with explicit nucleation and SOA scheme performs well in terms of correlation coefficient, <i>R</i><sup>2</sup> = 0.41 and a bias of −6%. NorESM generally overestimates the amplitude of the seasonal cycle, possibly due to underestimated sinks or exaggerated sensitivity to biogenic precursors.

 References Abdul-Razzak, H. and Ghan, S. J.: A parameterization of aerosol activation 2. Multiple aerosol types, J. Geophys. Res., 105, 6837–6844, 2000. Adams, P. and Seinfeld, J.: Predicting global aerosol size distributions in general circulation models, J. Geophys. Res.-Atmos., 107, 4-1–4-23, <a href="http://dx.doi.org/10.1097/00132985-200204000-00004">https://doi.org/10.1097/00132985-200204000-00004</a>, 2002. Allan, J., Bower, K., Coe, H., Boudries, H., Jayne, J., Canagaratna, M., Millet, D., Goldstein, A., Quinn, P., Weber, R., and Worsnop, D.: Submicron aerosol composition at Trinidad Head, California, during ITCT 2K2: Its relationship with gas phase volatile organic carbon and assessment of instrument performance, J. Geophys. Res., 109, D23S24, <a href="http://dx.doi.org/10.1029/2003JD004208">https://doi.org/10.1029/2003JD004208</a>, 2004. Amundsen, C., Hanssen, J., Semb, A., and Steinnes, E.: Long-range atmospheric transport of trace elements to southern Norway, Atmos. Environ., 26, 1309–1324, 1992. Anenberg, S., Schwartz, J., Shindell, D., Amann, M., Faluvegi, G., Klimont, Z., Janssens-Maenhout, G., Pozzoli, L., van Dingenen, R., Vignati, E., Emberson, L., Muller, N., Jason West, J., Williams, M., Demkine, V., Kevin Hicks, W., Kuylenstierna, J., Raes, F., and Ramanathan, V.: Global air quality and health co-benefits of mitigating near-term climate change through methane and black carbon emission controls, Environ. Health Persp., 120, 831–839, <a href="http://dx.doi.org/10.1289/ehp.1104301">https://doi.org/10.1289/ehp.1104301</a>, 2012. Anttila, T., Kerminen, V.-M., and Lehtinen, K.: Parameterizing the formation rate of new particles: The effect of nuclei self-coagulation, J. Aerosol Sci., 41, 621–636, <a href="http://dx.doi.org/10.1016/j.jaerosci.2010.04.008">https://doi.org/10.1016/j.jaerosci.2010.04.008</a>, 2010. Asmi, A., Wiedensohler, A., Laj, P., Fjaeraa, A.-M., Sellegri, K., Birmili, W., Weingartner, E., Baltensperger, U., Zdimal, V., Zikova, N., Putaud, J.-P., Marinoni, A., Tunved, P., Hansson, H.-C., Fiebig, M., Kivekäs, N., Lihavainen, H., Asmi, E., Ulevicius, V., Aalto, P. P., Swietlicki, E., Kristensson, A., Mihalopoulos, N., Kalivitis, N., Kalapov, I., Kiss, G., de Leeuw, G., Henzing, B., Harrison, R. M., Beddows, D., O'Dowd, C., Jennings, S. G., Flentje, H., Weinhold, K., Meinhardt, F., Ries, L., and Kulmala, M.: Number size distributions and seasonality of submicron particles in Europe 2008–2009, Atmos. Chem. Phys., 11, 5505–5538, <a href="http://dx.doi.org/10.5194/acp-11-5505-2011">https://doi.org/10.5194/acp-11-5505-2011</a>, 2011. Bentsen, M., Bethke, I., Debernard, J. B., Iversen, T., Kirkevåg, A., Seland, Ø., Drange, H., Roelandt, C., Seierstad, I. A., Hoose, C., and Kristjánsson, J. E.: The Norwegian Earth System Model, NorESM1-M – Part 1: Description and basic evaluation of the physical climate, Geosci. Model Dev., 6, 687–720, <a href="http://dx.doi.org/10.5194/gmd-6-687-2013">https://doi.org/10.5194/gmd-6-687-2013</a>, 2013. Birmili, W., Berresheim, H., Plass-Dülmer, C., Elste, T., Gilge, S., Wiedensohler, A., and Uhrner, U.: The Hohenpeissenberg aerosol formation experiment (HAFEX): a long-term study including size-resolved aerosol, H<sub>2</sub>SO<sub>4</sub>, OH, and monoterpenes measurements, Atmos. Chem. Phys., 3, 361–376, <a href="http://dx.doi.org/10.5194/acp-3-361-2003">https://doi.org/10.5194/acp-3-361-2003</a>, 2003. Birmili, W., Ries, L., Sohmer, R., Anastou, A., Sonntag, A., König, K., and Levin, I.: Fine and ultrafine aerosol particles at the GAW station Schneefernerhaus/Zugspitze, Gefahrstoffe Reinhalt. L., 69, 31–35, 2009a. Birmili, W., Weinhold, K., Nordmann, S., Wiedensohler, A., Spindler, G., Müller, K., Herrmann, H., Gnauk, T., Pitz, M., Cyrys, J., Flentje, H., Nickel, C., Kuhlbusch, T., Löschau, G., Haase, D., Meinhardt, F., Schwerin, A., Ries, L., and Wirtz, K.: Atmospheric aerosol measurements in the German Ultrafine Aerosol Network (GUAN) – Part 1: Soot and particle number size distributions, Gefahrstoffe Reinhalt. L., 69, 137–145, 2009b. Bodhaine, B.: Aerosol measurements at four background sites ( Barrow Alaska, Mauna Loa, Hawaii, American Samoa, South Pole)., J. Geophys. Res., 88, 10735–10768, 1983. Bodhaine, B.: Barrow surface aerosol: 1976–1986, Atmos. Environ., 23, 2357–2369, 1989. Bodhaine, B. and DeLuisi, J.: An aerosol climatology of Samoa, J. Atmos. Chem., 3, 107–122, <a href="http://dx.doi.org/10.1007/BF00049371">https://doi.org/10.1007/BF00049371</a>, 1985. Bodhaine, B., Deluisi, J., and Harris, J.: Aerosol measurements at the South Pole, Tellus, 38, 223–235, 1986. Bonasoni, P., Stohl, A., Cristofanelli, P., Calzolari, F., Colombo, T., and Evangelisti, F.: Background ozone variations at Mt. Cimone Station, Atmos. Environ., 34, 5183–5189, 2000. Bonasoni, P., Laj, P., Marinoni, A., Sprenger, M., Angelini, F., Arduini, J., Bonafè, U., Calzolari, F., Colombo, T., Decesari, S., Di Biagio, C., di Sarra, A. G., Evangelisti, F., Duchi, R., Facchini, MC., Fuzzi, S., Gobbi, G. P., Maione, M., Panday, A., Roccato, F., Sellegri, K., Venzac, H., Verza, GP., Villani, P., Vuillermoz, E., and Cristofanelli, P.: Atmospheric Brown Clouds in the Himalayas: first two years of continuous observations at the Nepal Climate Observatory-Pyramid (5079 m), Atmos. Chem. Phys., 10, 7515–7531, <a href="http://dx.doi.org/10.5194/acp-10-7515-2010">https://doi.org/10.5194/acp-10-7515-2010</a>, 2010. Bond, T. C., Doherty, S. J., Fahey, D. W., Forster, P. M., Berntsen, T., DeAngelo, B. J., Flanner, M. G., Ghan, S., Kärcher, B., Koch, D., Kinne, S., Kondo, Y., Quinn, P. K., Sarofim, M. C., Schultz, M. G., Schulz, M., Venkataraman, C., Zhang, H., Zhang, S., Bellouin, N., Guttikunda, S. K., Hopke, P. K., Jacobson, M. Z., Kaiser, J. W., Klimont, Z., Lohmann, U., Schwarz, J. P., Shindell, D., Storelvmo, T., Warren, S. G., and Zender, C. S.: Bounding the role of black carbon in the climate system: A scientific assessment, J. Geophys. Res.-Atmos., 118, 5380–5552, <a href="http://dx.doi.org/10.1002/jgrd.50171">https://doi.org/10.1002/jgrd.50171</a>, 2013. Boy, M., Kazil, J., Lovejoy, E., Guenther, A., and Kulmala, M.: Relevance of ion-induced nucleation of sulfuric acid and water in the lower troposphere over the boreal forest at northern latitudes, Atmos. Res., 90, 151–158, <a href="http://dx.doi.org/10.1016/j.atmosres.2008.01.002">https://doi.org/10.1016/j.atmosres.2008.01.002</a>, 2008. Brunke, E.-G., Ebinghaus, R., Kock, H. H., Labuschagne, C., and Slemr, F.: Emissions of mercury in southern Africa derived from long-term observations at Cape Point, South Africa, Atmos. Chem. Phys., 12, 7465–7474, <a href="http://dx.doi.org/10.5194/acp-12-7465-2012">https://doi.org/10.5194/acp-12-7465-2012</a>, 2012. Charron, A., Birmili, W., and Harrison, R.: Factors influencing new particle formation at the rural site, Harwell, United Kingdom, J. Geophys. Res.-Atmos., 112, D14210, <a href="http://dx.doi.org/10.1029/2007JD008425">https://doi.org/10.1029/2007JD008425</a>, 2007. Clarke, A. and Kapustin, V.: Hemispheric aerosol vertical profiles: Anthropogenic impacts on optical depth and cloud nuclei, Science, 329, 1488–1492, <a href="http://dx.doi.org/10.1126/science.1188838">https://doi.org/10.1126/science.1188838</a>, 2010. Dal Maso, M., Sogacheva, L., Anisimov, M., Arshinov, M., Baklanov, A., Belan, B., Khodzher, T., Obolkin, V., Staroverova, A., Vlasov, A., Zagaynov, V., Lushnikov, A., Lyubovtseva, Y., Riipinen, I., Kerminen, V.-M., and Kulmala, M.: Aerosol particle formation events at two Siberian stations inside the boreal forest, Boreal Environ. Res., 13, 81–92, 2008. Delene, D. and Ogren, J.: Variability of aerosol optical properties at four North American surface monitoring sites, J. Atmos. Sci., 59, 1135–1150, 2002. 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, <a href="http://dx.doi.org/10.5194/acp-6-4321-2006">https://doi.org/10.5194/acp-6-4321-2006</a>, 2006. Ehn, M., Thornton, J., Kleist, E., Sipilä, M., Junninen, H., Pullinen, I., Springer, M., Rubach, F., Tillmann, R., Lee, B., Lopez-Hilfiker, F., Andres, S., Acir, I.-H., Rissanen, M., Jokinen, T., Schobesberger, S., Kangasluoma, J., Kontkanen, J., Nieminen, T., Kurtén, T., Nielsen, L., Jørgensen, S., Kjaergaard, H., Canagaratna, M., Maso, M., Berndt, T., Petäjä, T., Wahner, A., Kerminen, V.-M., Kulmala, M., Worsnop, D., Wildt, J., and Mentel, T.: A large source of low-volatility secondary organic aerosol, Nature, 506, 476–479, <a href="http://dx.doi.org/10.1038/nature13032">https://doi.org/10.1038/nature13032</a>, 2014. Engler, C., Rose, D., Wehner, B., Wiedensohler, A., Brüggemann, E., Gnauk, T., Spindler, G., Tuch, T., and Birmili, W.: Size distributions of non-volatile particle residuals (D<sub>p</sub><800 nm) at a rural site in Germany and relation to air mass origin, Atmos. Chem. Phys., 7, 5785–5802, <a href="http://dx.doi.org/10.5194/acp-7-5785-2007">https://doi.org/10.5194/acp-7-5785-2007</a>, 2007. Forster, P., Ramaswamy, V., Artaxo, P., Berntsen, T., Betts, R., Fahey, D. W., Haywood, J., Lean, J., Lowe, D. C., Myhre, G., Nganga, J., Prinn, R., Raga, G., Schulz, M., and Van Dorland, R.: Climate Change 2007, The Physical Science Basis, Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge Univ. Press, Cambridge, UK, and New York, NY, USA, 2007. Fountoukis, C., Riipinen, I., Denier van der Gon, H. A. C., Charalampidis, P. E., Pilinis, C., Wiedensohler, A., O'Dowd, C., Putaud, J. P., Moerman, M., and Pandis, S. N.: Simulating ultrafine particle formation in Europe using a regional CTM: contribution of primary emissions versus secondary formation to aerosol number concentrations, Atmos. Chem. Phys., 12, 8663–8677, <a href="http://dx.doi.org/10.5194/acp-12-8663-2012">https://doi.org/10.5194/acp-12-8663-2012</a>, 2012. García, M. I., Rodríguez, S., González, Y., and García, R. D.: Climatology of new particle formation events in the subtropical North Atlantic free troposphere at Izaña GAW observatory, Atmos. Chem. Phys. Discuss., 13, 24127–24169, <a href="http://dx.doi.org/10.5194/acpd-13-24127-2013">https://doi.org/10.5194/acpd-13-24127-2013</a>, 2013. Gaydos, T. M., Stanier, C. O., and Pandis, S. N.: Modeling of in situ ultrafine atmospheric particle formation in the eastern United States, J. Geophys. Res.-Atmos., 110, D07S12, <a href="http://dx.doi.org/10.1029/2004JD004683">https://doi.org/10.1029/2004JD004683</a>, 2005. Gent, P., Danabasoglu, G., Donner, L., Holland, M., Hunke, E., Jayne, S., Lawrence, D., Neale, R., Rasch, P., Vertenstein, M., Worley, P., Yang, Z., and Zhang, M.: The community climate system model version 4, J. Climate, 24, 4973–4991, <a href="http://dx.doi.org/10.1175/2011JCLI4083.1">https://doi.org/10.1175/2011JCLI4083.1</a>, 2011. Ghan, S., Easter, R., Chapman, E., Abdul-Razzak, H., Zhang, Y., Leung, L., Laulainen, N., Saylor, R., and Zaveri, R.: A physically based estimate of radiative forcing by anthropogenic sulfate aerosol, J. Geophys. Res.-Atmos., 106, 5279–5293, 2001. Gioda, A., Reyes-Rodrìguez, G., Santos-Figueroa, G., Collett Jr., J., Decesari, S., Ramos, M., Bezerra Netto, H., De Aquino Neto, F., and Mayol-Bracero, O.: Speciation of water-soluble inorganic, organic, and total nitrogen in a background marine environment: Cloud water, rainwater, and aerosol particles, J. Geophys. Res.-Atmos., 116, D05203, <a href="http://dx.doi.org/10.1029/2010JD015010">https://doi.org/10.1029/2010JD015010</a>, 2011. Gonzàlez, Y., Rodrìguez, S., Guerra Garcìa, J., Trujillo, J., and Garcìa, R.: Ultrafine particles pollution in urban coastal air due to ship emissions, Atmos. Environ., 45, 4907–4914, <a href="http://dx.doi.org/10.1016/j.atmosenv.2011.06.002">https://doi.org/10.1016/j.atmosenv.2011.06.002</a>, 2011. Gras, J. L.: CN, CCN and particle size in Southern Ocean air at Cape Grim, Atmos. Res., 35, 233–251, 1995. Gruening, C., Adam, M., Cavalli, F., Cavalli, P., Dell’Acqua, A., Martins Dos Santos, S., Pagliari, V., Roux, D., and Putaud, J.-P.: JRC Ispra EMEP GAW Regional Station for Atmos. Res. 2008 Report, Tech. Rep. JRC55382, European Commission, <a href="http://publications.jrc.ec.europa.eu/repository/handle/111111111/538">http://publications.jrc.ec.europa.eu/repository/handle/111111111/538</a> (last access: 15 January 2014), 2009. Guenther, A., Karl, T., Harley, P., Wiedinmyer, C., Palmer, P. I., and Geron, C.: Estimates of global terrestrial isoprene emissions using MEGAN (Model of Emissions of Gases and Aerosols from Nature), Atmos. Chem. Phys., 6, 3181–3210, <a href="http://dx.doi.org/10.5194/acp-6-3181-2006">https://doi.org/10.5194/acp-6-3181-2006</a>, 2006. Hallar, A., Lowenthal, D., Chirokova, G., Borys, R., and Wiedinmyer, C.: Persistent daily new particle formation at a mountain-top location, Atmos. Environ., 45, 4111–4115, <a href="http://dx.doi.org/10.1016/j.atmosenv.2011.04.044">https://doi.org/10.1016/j.atmosenv.2011.04.044</a>, 2011. Hallar, A., Lowenthal, D., Clegg, S., Samburova, V., Taylor, N., Mazzoleni, L., Zielinska, B., Kristensen, T., Chirokova, G., McCubbin, I., Dodson, C., and Collins, D.: Chemical and Hygroscopic Properties of Aerosol Organics at Storm Peak Laboratory, J. Geophys. Res.-Atmos., 118, 4767–4779, <a href="http://dx.doi.org/10.1002/jgrd.50373">https://doi.org/10.1002/jgrd.50373</a>, 2013. Hamed, A., Joutsensaari, J., Mikkonen, S., Sogacheva, L., Dal Maso, M., Kulmala, M., Cavalli, F., Fuzzi, S., Facchini, M. C., Decesari, S., Mircea, M., Lehtinen, K. E. J., and Laaksonen, A.: Nucleation and growth of new particles in Po Valley, Italy, Atmos. Chem. Phys., 7, 355–376, <a href="http://dx.doi.org/10.5194/acp-7-355-2007">https://doi.org/10.5194/acp-7-355-2007</a>, 2007. Hansen, G., Aspmo, K., Berg, T., Edvardsen, K., Fiebig, M., Kallenborn, R., Krognes, T., Lunder, C., Stebel, K., Schmidbauer, N., Solberg, S., and Yttri, K.: Atmospheric monitoring at the Norwegian Antarctic station Troll: measurement programme and first results, Polar Res., 28, 353–363, <a href="http://dx.doi.org/10.1111/j.1751-8369.2009.00134.x">https://doi.org/10.1111/j.1751-8369.2009.00134.x</a>, 2009. Hari, P. and Kulmala, M.: Station for Measuring Ecosystem-Atmosphere Relations (SMEAR II), Boreal Environ. Res., 10, 315–322, 2005. Heintzenberg, J., Covert, D. C., and van Dingenen, R.: Size distribution and chemical composition of marine aerosols: a compilation and review, Tellus, 52, 1104–1122, 2000. Henne, S., Brunner, D., Folini, D., Solberg, S., Klausen, J., and Buchmann, B.: Assessment of parameters describing representativeness of air quality in-situ measurement sites, Atmos. Chem. Phys., 10, 3561–3581, <a href="http://dx.doi.org/10.5194/acp-10-3561-2010">https://doi.org/10.5194/acp-10-3561-2010</a>, 2010. Hoyle, C. R., Berntsen, T., Myhre, G., and Isaksen, I. S. A.: Secondary organic aerosol in the global aerosol – chemical transport model Oslo CTM2, Atmos. Chem. Phys., 7, 5675–5694, <a href="http://dx.doi.org/10.5194/acp-7-5675-2007">https://doi.org/10.5194/acp-7-5675-2007</a>, 2007. Iversen, T., Bentsen, M., Bethke, I., Debernard, J. B., Kirkevåg, A., Seland, Ø., Drange, H., Kristjansson, J. E., Medhaug, I., Sand, M., and Seierstad, I. A.: The Norwegian Earth System Model, NorESM1-M – Part 2: Climate response and scenario projections, Geosci. Model Dev., 6, 389–415, <a href="http://dx.doi.org/10.5194/gmd-6-389-2013">https://doi.org/10.5194/gmd-6-389-2013</a>, 2013. Järvinen, E., Virkkula, A., Nieminen, T., Aalto, P. P., Asmi, E., Lanconelli, C., Busetto, M., Lupi, A., Schioppo, R., Vitale, V., Mazzola, M., Petäjä, T., Kerminen, V.-M., and Kulmala, M.: Seasonal cycle and modal structure of particle number size distribution at Dome C, Antarctica, Atmos. Chem. Phys., 13, 7473–7487, <a href="http://dx.doi.org/10.5194/acp-13-7473-2013">https://doi.org/10.5194/acp-13-7473-2013</a>, 2013. Kelly, G., Taubman, B., Perry, L., Sherman, J., Soulé, P., and Sheridan, P.: Relationships between aerosols and precipitation in the southern Appalachian Mountains, Int. J. Climatol., 33, 3016–3028, <a href="http://dx.doi.org/10.1002/joc.3632">https://doi.org/10.1002/joc.3632</a>, 2013. Kerminen, V. M. and Kulmala, M.: Analytical formulae connecting the "real" and the "apparent" nucleation rate and the nuclei number concentration for atmospheric nucleation events, J. Aerosol Sci., 33, 609–622, 2002. Keskinen, H., Virtanen, A., Joutsensaari, J., Tsagkogeorgas, G., Duplissy, J., Schobesberger, S., Gysel, M., Riccobono, F., Slowik, J. G., Bianchi, F., Yli-Juuti, T., Lehtipalo, K., Rondo, L., Breitenlechner, M., Kupc, A., Almeida, J., Amorim, A., Dunne, E. M., Downard, A. J., Ehrhart, S., Franchin, A., Kajos, M.K., Kirkby, J., Kürten, A., Nieminen, T., Makhmutov, V., Mathot, S., Miettinen, P., Onnela, A., Petäjä, T., Praplan, A., Santos, F. D., Schallhart, S., Sipilä, M., Stozhkov, Y., Tomé, A., Vaattovaara, P., Wimmer, D., Prevot, A., Dommen, J., Donahue, N. M., Flagan, R.C., Weingartner, E., Viisanen, Y., Riipinen, I., Hansel, A., Curtius, J., Kulmala, M., Worsnop, D. R., Baltensperger, U., Wex, H., Stratmann, F., and Laaksonen, A.: Evolution of particle composition in CLOUD nucleation experiments, Atmos. Chem. Phys., 13, 5587–5600, <a href="http://dx.doi.org/10.5194/acp-13-5587-2013">https://doi.org/10.5194/acp-13-5587-2013</a>, 2013. Kirkevåg, A., Iversen, T., Seland, Ø., Hoose, C., Kristjánsson, J. E., Struthers, H., Ekman, A. M. L., Ghan, S., Griesfeller, J., Nilsson, E. D., and Schulz, M.: Aerosol-climate interactions in the Norwegian Earth System Model – NorESM1-M, Geosci. Model Dev., 6, 207–244, <a href="http://dx.doi.org/10.5194/gmd-6-207-2013">https://doi.org/10.5194/gmd-6-207-2013</a>, 2013. Kiss, G., Varga, B., Galambos, I., and Ganszky, I.: Characterization of water-soluble organic matter isolated from atmospheric fine aerosol, J. Geophys. Res.-Atmos., 107, 8339, <a href="http://dx.doi.org/10.1029/2001JD000603">https://doi.org/10.1029/2001JD000603</a>, 2002. Komppula, M., Lihavainen, H., Hatakka, J., Paatero, J., Aalto, P., Kulmala, M., and Viisanen, Y.: Observations of new particle formation and size distributions at two different heights and surroundings in subarctic area in northern Finland, J. Geophys. Res., 108, 4295, 10.1029/2002JD00, 2003. Komppula, M., Lihavainen, H., Hyvärinen, A.-P., Kerminen, V.-M., Panwar, T., Sharma, V., and Viisanen, Y.: Physical properties of aerosol particles at a Himalayan background site in India, J. Geophys. Res.-Atmos., 114, D12202, <a href="http://dx.doi.org/10.1029/2008JD011007">https://doi.org/10.1029/2008JD011007</a>, 2009. Kristensson, A., Dal Maso, M., Swietlicki, E., Hussein, T., Zhou, J., Kerminen, V.-M., and Kulmala, M.: Characterization of new particle formation events at a background site in southern Sweden: Relation to air mass history, Tellus B, 60, 330–344, <a href="http://dx.doi.org/10.1111/j.1600-0889.2008.00345.x">https://doi.org/10.1111/j.1600-0889.2008.00345.x</a>, 2008. Kulmala, M., Lehtinen, K. E. J., and Laaksonen, A.: Cluster activation theory as an explanation of the linear dependence between formation rate of 3nm particles and sulphuric acid concentration, Atmos. Chem. Phys., 6, 787–793, <a href="http://dx.doi.org/10.5194/acp-6-787-2006">https://doi.org/10.5194/acp-6-787-2006</a>, 2006. Kulmala, M., Asmi, A., Lappalainen, H. K., Baltensperger, U., Brenguier, J.-L., Facchini, M. C., Hansson, H.-C., Hov, Ø., O'Dowd, C. D., Pöschl, U., Wiedensohler, A., Boers, R., Boucher, O., de Leeuw, G., Denier van der Gon, H. A. C., Feichter, J., Krejci, R., Laj, P., Lihavainen, H., Lohmann, U., McFiggans, G., Mentel, T., Pilinis, C., Riipinen, I., Schulz, M., Stohl, A., Swietlicki, E., Vignati, E., Alves, C., Amann, M., Ammann, M., Arabas, S., Artaxo, P., Baars, H., Beddows, D. C. S., Bergström, R., Beukes, J. P., Bilde, M., Burkhart, J. F., Canonaco, F., Clegg, S. L., Coe, H., Crumeyrolle, S., D'Anna, B., Decesari, S., Gilardoni, S., Fischer, M., Fjaeraa, A. M., Fountoukis, C., George, C., Gomes, L., Halloran, P., Hamburger, T., Harrison, R. M., Herrmann, H., Hoffmann, T., Hoose, C., Hu, M., Hyvärinen, A., Hõrrak, U., Iinuma, Y., Iversen, T., Josipovic, M., Kanakidou, M., Kiendler-Scharr, A., Kirkevåg, A., Kiss, G., Klimont, Z., Kolmonen, P., Komppula, M., Kristjánsson, J.-E., Laakso, L., Laaksonen, A., Labonnote, L., Lanz, V. A., Lehtinen, K. E. J., Rizzo, L. V., Makkonen, R., Manninen, H. E., McMeeking, G., Merikanto, J., Minikin, A., Mirme, S., Morgan, W. T., Nemitz, E., O'Donnell, D., Panwar, T. S., Pawlowska, H., Petzold, A., Pienaar, J. J., Pio, C., Plass-Duelmer, C., Prévôt, A. S. H., Pryor, S., Reddington, C. L., Roberts, G., Rosenfeld, D., Schwarz, J., Seland, Ø., Sellegri, K., Shen, X. J., Shiraiwa, M., Siebert, H., Sierau, B., Simpson, D., Sun, J. Y., Topping, D., Tunved, P., Vaattovaara, P., Vakkari, V., Veefkind, J. P., Visschedijk, A., Vuollekoski, H., Vuolo, R., Wehner, B., Wildt, J., Woodward, S., Worsnop, D. R., van Zadelhoff, G.-J., Zardini, A. A., Zhang, K., van Zyl, P. G., Kerminen, V.-M., S Carslaw, K., and Pandis, S. N.: General overview: European Integrated project on Aerosol Cloud Climate and Air Quality interactions (EUCAARI) – integrating aerosol research from nano to global scales, Atmos. Chem. Phys., 11, 13061–13143, <a href="http://dx.doi.org/10.5194/acp-11-13061-2011">https://doi.org/10.5194/acp-11-13061-2011</a>, 2011. Kyrö, E.-M., Kerminen, V.-M., Virkkula, A., Dal Maso, M., Parshintsev, J., Ruíz-Jimenez, J., Forsström, L., Manninen, H. E., Riekkola, M.-L., Heinonen, P., and Kulmala, M.: Antarctic new particle formation from continental biogenic precursors, Atmos. Chem. Phys., 13, 3527–3546, <a href="http://dx.doi.org/10.5194/acp-13-3527-2013">https://doi.org/10.5194/acp-13-3527-2013</a>, 2013. Laakso, L., Merikanto, J., Vakkari, V., Laakso, H., Kulmala, M., Molefe, M., Kgabi, N., Mabaso, D., Carslaw, K. S., Spracklen, D. V., Lee, L. A., Reddington, C. L., and Kerminen, V.-M.: Boundary layer nucleation as a source of new CCN in savannah environment, Atmos. Chem. Phys., 13, 1957–1972, <a href="http://dx.doi.org/10.5194/acp-13-1957-2013">https://doi.org/10.5194/acp-13-1957-2013</a>, 2013. Labuschagne, C., Brunke, E.-G., Beukes, J., van Zyl, P., and Laakso, L.: Aerosols in a coastal environment: What does 6 years of measurements tell us?, South African Society for Atmospheric Sciences, Cape Town 28th Annual Conference, 26–27 September 2012, ISBN 978-0-620-53375-1, 2012. Lamarque, J.-F., Bond, T. C., Eyring, V., Granier, C., Heil, A., Klimont, Z., Lee, D., Liousse, C., Mieville, A., Owen, B., Schultz, M. G., Shindell, D., Smith, S. J., Stehfest, E., Van Aardenne, J., Cooper, O. R., Kainuma, M., Mahowald, N., McConnell, J. R., Naik, V., Riahi, K., and van Vuuren, D. P.: Historical (1850–2000) gridded anthropogenic and biomass burning emissions of reactive gases and aerosols: methodology and application, Atmos. Chem. Phys., 10, 7017–7039, <a href="http://dx.doi.org/10.5194/acp-10-7017-2010">https://doi.org/10.5194/acp-10-7017-2010</a>, 2010. Langley, L., Leaitch, W. R., Lohmann, U., Shantz, N. C., and Worsnop, D. R.: Contributions from DMS and ship emissions to CCN observed over the summertime North Pacific, Atmos. Chem. Phys., 10, 1287–1314, <a href="http://dx.doi.org/10.5194/acp-10-1287-2010">https://doi.org/10.5194/acp-10-1287-2010</a>, 2010. Lehtinen, K., Dal Maso, M., Kulmala, M., and Kerminen, V.-M.: Estimating nucleation rates from apparent particle formation rates and vice versa: Revised formulation of the Kerminen-Kulmala equation, J. Aerosol Sci., 38, 988–994, <a href="http://dx.doi.org/10.1016/j.jaerosci.2007.06.009">https://doi.org/10.1016/j.jaerosci.2007.06.009</a>, 2007. Lohmann, U. and Feichter, J.: Global indirect aerosol effects: a review, Atmos. Chem. Phys., 5, 715–737, <a href="http://dx.doi.org/10.5194/acp-5-715-2005">https://doi.org/10.5194/acp-5-715-2005</a>, 2005. Lucas, D. and Akimoto, H.: Evaluating aerosal nucleation parameterizations in a global atmospheric model, Geophys. Res. Lett., 33, L10808, <a href="http://dx.doi.org/10.1029/2006GL025672">https://doi.org/10.1029/2006GL025672</a>, 2006. Maier-Reimer, E.: Geochemical cycles in an ocean general circulation model. Preindustrial tracer distributions, Global Biogeochem. Cy., 7, 645–677, <a href="http://dx.doi.org/10.1029/93GB01355">https://doi.org/10.1029/93GB01355</a>, 1993. Maier-Reimer, E., Kriest, I., Segschneider, J., and Wetzel, P.: The Hamburg oceanic carbon cycle circulation model HAMOCC5.1 Technical Description Release 1.1, Tech. Rep., Reports on Earth System Science, Max Planck Institute for Meteorology, Hamburg, 2005. Makkonen, R., Asmi, A., Korhonen, H., Kokkola, H., Järvenoja, S., Räisänen, P., Lehtinen, K. E. J., Laaksonen, A., Kerminen, V.-M., Järvinen, H., Lohmann, U., Bennartz, R., Feichter, J., and Kulmala, M.: Sensitivity of aerosol concentrations and cloud properties to nucleation and secondary organic distribution in ECHAM5-HAM global circulation model, Atmos. Chem. Phys., 9, 1747–1766, <a href="http://dx.doi.org/10.5194/acp-9-1747-2009">https://doi.org/10.5194/acp-9-1747-2009</a>, 2009. Makkonen, R., Asmi, A., Kerminen, V.-M., Boy, M., Arneth, A., Guenther, A., and Kulmala, M.: BVOC-aerosol-climate interactions in the global aerosol-climate model ECHAM5.5-HAM2, Atmos. Chem. Phys., 12, 10077–10096, <a href="http://dx.doi.org/10.5194/acp-12-10077-2012">https://doi.org/10.5194/acp-12-10077-2012</a>, 2012a. Makkonen, R., Asmi, A., Kerminen, V.-M., Boy, M., Arneth, A., Hari, P., and Kulmala, M.: Air pollution control and decreasing new particle formation lead to strong climate warming, Atmos. Chem. Phys., 12, 1515–1524, <a href="http://dx.doi.org/10.5194/acp-12-1515-2012">https://doi.org/10.5194/acp-12-1515-2012</a>, 2012b. 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., 3, 519–551, <a href="http://dx.doi.org/10.5194/gmd-3-519-2010">https://doi.org/10.5194/gmd-3-519-2010</a>, 2010. Marinoni, A., Cristofanelli, P., Calzolari, F., Roccato, F., Bonafé, U., and Bonasoni, P.: Continous measurements of aerosol physical parameters at the Mt. Cimone GAW station (2165 m asl, Italy), Sci. Total Environ., 391, 231–251, 2008. Merikanto, J., Spracklen, D. V., Mann, G. W., Pickering, S. J., and Carslaw, K. S.: Impact of nucleation on global CCN, Atmos. Chem. Phys., 9, 8601–8616, <a href="http://dx.doi.org/10.5194/acp-9-8601-2009">https://doi.org/10.5194/acp-9-8601-2009</a>, 2009. Metzger, A., Verheggen, B., Dommen, J., Duplissy, J., Prevot, A. S. H., Weingartner, E., Riipinen, I., Kulmala, M., Spracklen, D. V., Carslaw, K. S., and Baltensperger, U.: Evidence for the role of organics in aerosol particle formation under atmospheric conditions, P. Natl. Acad. Sci. USA, 107, 6646–6651, <a href="http://dx.doi.org/10.1073/pnas.0911330107">https://doi.org/10.1073/pnas.0911330107</a>, 2010. Mihalopoulos, N., Stephanou, E., Kanakidou, M., Pilitsidis, S., and Bousquet, P.: Tropospheric aerosol ionic composition in the Eastern Mediterranean region, Tellus B, 49, 314–326, 1997. Myhre, G., Samset, B. H., Schulz, M., Balkanski, Y., Bauer, S., Berntsen, T. K., Bian, H., Bellouin, N., Chin, M., Diehl, T., Easter, R. C., Feichter, J., Ghan, S. J., Hauglustaine, D., Iversen, T., Kinne, S., Kirkevåg, A., Lamarque, J.-F., Lin, G., Liu, X., Lund, M. T., Luo, G., Ma, X., van Noije, T., Penner, J. E., Rasch, P. J., Ruiz, A., Seland, Ø., Skeie, R. B., Stier, P., Takemura, T., Tsigaridis, K., Wang, P., Wang, Z., Xu, L., Yu, H., Yu, F., Yoon, J.-H., Zhang, K., Zhang, H., and Zhou, C.: Radiative forcing of the direct aerosol effect from AeroCom Phase II simulations, Atmos. Chem. Phys., 13, 1853–1877, <a href="http://dx.doi.org/10.5194/acp-13-1853-2013">https://doi.org/10.5194/acp-13-1853-2013</a>, 2013. Nojarov, P., Ivanov, P., Kalapov, I., Penev, I., and Drenska, M.: Connection between ozone concentration and atmosphere circulation at peak Moussala, Theor. Appl. Climatol., 98, 201–208, <a href="http://dx.doi.org/10.1007/s00704-009-0173-2">https://doi.org/10.1007/s00704-009-0173-2</a>, 2009. O'Dowd, C. and Hoffmann, T.: Coastal new particle formation: A review of the current state-of-the-art, Environ. Chem., 2, 245–255, <a href="http://dx.doi.org/10.1071/EN05077">https://doi.org/10.1071/EN05077</a>, 2005. O'Dowd, C. D., Hill, M. K., Smith, M. H., Geever, M., and Jennings, S. G.: New particle formation: Nucleation rates & spatial scales in the coastal environment, J. Aerosol Sci., 29, S183–S184, 1998. Oleson, K., Lawrence, D. M., Bonan, G. B., Flanner, M., Kluzek, E., Lawrence, P., Levis, S., Swenson, S., Thornton, P., Dai, A., Decker, M., Dickinson, R., Feddema, J., Heald, C., Hoffman, F., Lamarque, J., Mahowald, N., Niu, G., Qian, T., Randerson, J., Running, S., Sakaguchi, K., Slater, A., Stockli, R., Wang, A., Yang, Z., Zeng, X., and Zeng., X.: Technical description of version 4.0 of the Community Land Model (CLM), NCAR Technical Note, NCAR/TN-478+STR, 2010. Otterå, O. H., Bentsen, M., Bethke, I., and Kvamstø, N. G.: Simulated pre-industrial climate in Bergen Climate Model (version 2): model description and large-scale circulation features, Geosci. Model Dev., 2, 197–212, <a href="http://dx.doi.org/10.5194/gmd-2-197-2009">https://doi.org/10.5194/gmd-2-197-2009</a>, 2009. Paasonen, P., Nieminen, T., Asmi, E., Manninen, H. E., Petäjä, T., Plass-Dülmer, C., Flentje, H., Birmili, W., Wiedensohler, A., Hõrrak, U., Metzger, A., Hamed, A., Laaksonen, A., Facchini, M. C., Kerminen, V.-M., and Kulmala, M.: On the roles of sulphuric acid and low-volatility organic vapours in the initial steps of atmospheric new particle formation, Atmos. Chem. Phys., 10, 11223–11242, <a href="http://dx.doi.org/10.5194/acp-10-11223-2010">https://doi.org/10.5194/acp-10-11223-2010</a>, 2010. Pandolfi, M., Cusack, M., Alastuey, A., and Querol, X.: Variability of aerosol optical properties in the Western Mediterranean Basin, Atmos. Chem. Phys., 11, 8189–8203, <a href="http://dx.doi.org/10.5194/acp-11-8189-2011">https://doi.org/10.5194/acp-11-8189-2011</a>, 2011. Pierce, J. R. and Adams, P. J.: Efficiency of cloud condensation nuclei formation from ultrafine particles, Atmos. Chem. Phys., 7, 1367–1379, <a href="http://dx.doi.org/10.5194/acp-7-1367-2007">https://doi.org/10.5194/acp-7-1367-2007</a>, 2007. Pierce, J. R. and Adams, P. J.: Uncertainty in global CCN concentrations from uncertain aerosol nucleation and primary emission rates, Atmos. Chem. Phys., 9, 1339–1356, <a href="http://dx.doi.org/10.5194/acp-9-1339-2009">https://doi.org/10.5194/acp-9-1339-2009</a>, 2009. Reddington, C. L., Carslaw, K. S., Spracklen, D. V., Frontoso, M. G., Collins, L., Merikanto, J., Minikin, A., Hamburger, T., Coe, H., Kulmala, M., Aalto, P., Flentje, H., Plass-Dülmer, C., Birmili, W., Wiedensohler, A., Wehner, B., Tuch, T., Sonntag, A., O'Dowd, C. D., Jennings, S. G., Dupuy, R., Baltensperger, U., Weingartner, E., Hansson, H.-C., Tunved, P., Laj, P., Sellegri, K., Boulon, J., Putaud, J.-P., Gruening, C., Swietlicki, E., Roldin, P., Henzing, J. S., Moerman, M., Mihalopoulos, N., Kouvarakis, G., Ždímal, V., Zíkovà, N., Marinoni, A., Bonasoni, P., and Duchi, R.: Primary versus secondary contributions to particle number concentrations in the European boundary layer, Atmos. Chem. Phys., 11, 12007–12036, <a href="http://dx.doi.org/10.5194/acp-11-12007-2011">https://doi.org/10.5194/acp-11-12007-2011</a>, 2011. Reddington, C. L., McMeeking, G., Mann, G. W., Coe, H., Frontoso, M. G., Liu, D., Flynn, M., Spracklen, D. V., and Carslaw, K. S.: The mass and number size distributions of black carbon aerosol over Europe, Atmos. Chem. Phys., 13, 4917–4939, <a href="http://dx.doi.org/10.5194/acp-13-4917-2013">https://doi.org/10.5194/acp-13-4917-2013</a>, 2013. Riipinen, I., Pierce, J. R., Yli-Juuti, T., Nieminen, T., Häkkinen, S., Ehn, M., Junninen, H., Lehtipalo, K., Petäjä, T., Slowik, J., Chang, R., Shantz, N. C., Abbatt, J., Leaitch, W. R., Kerminen, V.-M., Worsnop, D. R., Pandis, S. N., Donahue, N. M., and Kulmala, M.: Organic condensation: a vital link connecting aerosol formation to cloud condensation nuclei (CCN) concentrations, Atmos. Chem. Phys., 11, 3865–3878, <a href="http://dx.doi.org/10.5194/acp-11-3865-2011">https://doi.org/10.5194/acp-11-3865-2011</a>, 2011. Rissler, J., Vestin, A., Swietlicki, E., Fisch, G., Zhou, J., Artaxo, P., and Andreae, M. O.: Size distribution and hygroscopic properties of aerosol particles from dry-season biomass burning in Amazonia, Atmos. Chem. Phys., 6, 471–491, <a href="http://dx.doi.org/10.5194/acp-6-471-2006">https://doi.org/10.5194/acp-6-471-2006</a>, 2006. Rodríguez, S., González, Y., Cuevas, E., Ramos, R., Romero, P. M., Abreu-Afonso, J., and Redondas, A.: Atmospheric nanoparticle observations in the low free troposphere during upward orographic flows at Izaña Mountain Observatory, Atmos. Chem. Phys., 9, 6319–6335, <a href="http://dx.doi.org/10.5194/acp-9-6319-2009">https://doi.org/10.5194/acp-9-6319-2009</a>, 2009. Russchenberg, H., Bosveld, F., Swart, D., Ten Brink, H., De Leeuw, G., Uijlenhoet, R., Arbesser-Rastburg, B., Van Der Marel, H., Ligthart, L., Boers, R., and Apituley, A.: Ground-based atmospheric remote sensing in the Netherlands: European outlook, IEICE Trans. Commun., E88-B, 2252–2257, <a href="http://dx.doi.org/10.1093/ietcom/e88-b.6.2252">https://doi.org/10.1093/ietcom/e88-b.6.2252</a>, 2005. Schmeissner, T., Krejci, R., Ström, J., Birmili, W., Wiedensohler, A., Hochschild, G., Gross, J., Hoffmann, P., and Calderon, S.: Analysis of number size distributions of tropical free tropospheric aerosol particles observed at Pico Espejo (4765 m a.s.l.), Venezuela, Atmos. Chem. Phys., 11, 3319–3332, <a href="http://dx.doi.org/10.5194/acp-11-3319-2011">https://doi.org/10.5194/acp-11-3319-2011</a>, 2011. Shaw, S., Gantt, B., and Meskhidze, N.: Production and Emissions of Marine Isoprene and Monoterpenes: A Review, Advances in Meteorology, 2010, Article ID 408696, <a href="http://dx.doi.org/10.1155/2010/408696">https://doi.org/10.1155/2010/408696</a>, 2010. Sihto, S.-L., Kulmala, M., Kerminen, V.-M., Dal Maso, M., Petäjä, T., Riipinen, I., Korhonen, H., Arnold, F., Janson, R., Boy, M., Laaksonen, A., and Lehtinen, K. E. J.: Atmospheric sulphuric acid and aerosol formation: implications from atmospheric measurements for nucleation and early growth mechanisms, Atmos. Chem. Phys., 6, 4079–4091, <a href="http://dx.doi.org/10.5194/acp-6-4079-2006">https://doi.org/10.5194/acp-6-4079-2006</a>, 2006. Spracklen, D. V., Pringle, K. J., Carslaw, K. S., Chipperfield, M. P., and Mann, G. W.: A global off-line model of size-resolved aerosol microphysics: I. Model development and prediction of aerosol properties, Atmos. Chem. Phys., 5, 2227–2252, <a href="http://dx.doi.org/10.5194/acp-5-2227-2005">https://doi.org/10.5194/acp-5-2227-2005</a>, 2005. Spracklen, D. V., Carslaw, K. S., Kulmala, M., Kerminen, V.-M., Mann, G. W., and Sihto, S.-L.: The contribution of boundary layer nucleation events to total particle concentrations on regional and global scales, Atmos. Chem. Phys., 6, 5631–5648, <a href="http://dx.doi.org/10.5194/acp-6-5631-2006">https://doi.org/10.5194/acp-6-5631-2006</a>, 2006. Spracklen, D. V., Carslaw, K. S., Merikanto, J., Mann, G. W., Reddington, C. L., Pickering, S., Ogren, J. A., Andrews, E., Baltensperger, U., Weingartner, E., Boy, M., Kulmala, M., Laakso, L., Lihavainen, H., Kivekäs, N., Komppula, M., Mihalopoulos, N., Kouvarakis, G., Jennings, S. G., O'Dowd, C., Birmili, W., Wiedensohler, A., Weller, R., Gras, J., Laj, P., Sellegri, K., Bonn, B., Krejci, R., Laaksonen, A., Hamed, A., Minikin, A., Harrison, R. M., Talbot, R., and Sun, J.: Explaining global surface aerosol number concentrations in terms of primary emissions and particle formation, Atmos. Chem. Phys., 10, 4775–4793, <a href="http://dx.doi.org/10.5194/acp-10-4775-2010">https://doi.org/10.5194/acp-10-4775-2010</a>, 2010. Spracklen, D. V., Jimenez, J. L., Carslaw, K. S., Worsnop, D. R., Evans, M. J., Mann, G. W., Zhang, Q., Canagaratna, M. R., Allan, J., Coe, H., McFiggans, G., Rap, A., and Forster, P.: Aerosol mass spectrometer constraint on the global secondary organic aerosol budget, Atmos. Chem. Phys., 11, 12109–12136, <a href="http://dx.doi.org/10.5194/acp-11-12109-2011">https://doi.org/10.5194/acp-11-12109-2011</a>, 2011. 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, <a href="http://dx.doi.org/10.5194/acp-5-1125-2005">https://doi.org/10.5194/acp-5-1125-2005</a>, 2005. Ström, J., Umegård, J., Tørseth, K., Tunved, P., Hansson, H.-C., Holmén, K., Wismann, V., Herber, A., and König-Langlo, G.: One year of particle size distribution and aerosol chemical composition measurements at the Zeppelin Station, Svalbard, March 2000–March 2001, Phys. Chem. Earth, 28, 1181–1190, <a href="http://dx.doi.org/10.1016/j.pce.2003.08.058">https://doi.org/10.1016/j.pce.2003.08.058</a>, 2003. Struthers, H., Ekman, A. M. L., Glantz, P., Iversen, T., Kirkevåg, A., Mårtensson, E. M., Seland, Ø., and Nilsson, E. D.: The effect of sea ice loss on sea salt aerosol concentrations and the radiative balance in the Arctic, Atmos. Chem. Phys., 11, 3459–3477, <a href="http://dx.doi.org/10.5194/acp-11-3459-2011">https://doi.org/10.5194/acp-11-3459-2011</a>, 2011. Tunved, P., Ström, J., and Hansson, H.-C.: An investigation of processes controlling the evolution of the boundary layer aerosol size distribution properties at the Swedish background station Aspvreten, Atmos. Chem. Phys., 4, 2581–2592, <a href="http://dx.doi.org/10.5194/acp-4-2581-2004">https://doi.org/10.5194/acp-4-2581-2004</a>, 2004. Tunved, P., Ström, J., and Krejci, R.: Arctic aerosol life cycle: linking aerosol size distributions observed between 2000 and 2010 with air mass transport and precipitation at Zeppelin station, Ny-Ålesund, Svalbard, Atmos. Chem. Phys., 13, 3643–3660, <a href="http://dx.doi.org/10.5194/acp-13-3643-2013">https://doi.org/10.5194/acp-13-3643-2013</a>, 2013. Ulevicius, V., Byčenkienė, S., Remeikis, V., Garbaras, A., Kecorius, S., Andriejauskienė, J., Jasinevičienė, D., and Mocnik, G.: Characterization of pollution events in the East Baltic region affected by regional biomass fire emissions, Atmos. Res., 98, 190–200, <a href="http://dx.doi.org/10.1016/j.atmosres.2010.03.021">https://doi.org/10.1016/j.atmosres.2010.03.021</a>, 2010. Vehkamäki, H., Kulmala, M., Napari, I., Lehtinen, K. E. J., Timmreck, C., Noppel, M., and Laaksonen, A.: An improved parameterization for sulfuric acid/water nucleation rates for tropospheric and stratospheric conditions, J. Geophys. Res., 107, 4622–4631, 2002. Veltkamp, P., Hansen, K., Barkley, R., and Sievers, R.: Principal component analysis of summertime organic aerosols at Niwot Ridge, Colorado, J. Geophys. Res.-Atmos., 101, 19495–19504, 1996. Venzac, H., Sellegri, K., Laj, P., Villani, P., Bonasoni, P., Marinoni, A., Cristofanelli, P., Calzolari, F., Fuzzi, S., Decesari, S., Facchini, M.-C., Vuillermoz, E., and Verza, G.: High frequency new particle formation in the Himalayas, P. Natl. Acad. Sci. USA, 105, 15666–15671, <a href="http://dx.doi.org/10.1073/pnas.0801355105">https://doi.org/10.1073/pnas.0801355105</a>, 2008. Venzac, H., Sellegri, K., Villani, P., Picard, D., and Laj, P.: Seasonal variation of aerosol size distributions in the free troposphere and residual layer at the puy de Dôme station, France, Atmos. Chem. Phys., 9, 1465–1478, <a href="http://dx.doi.org/10.5194/acp-9-1465-2009">https://doi.org/10.5194/acp-9-1465-2009</a>, 2009. Vertenstein, M., Craig, T., Middleton, A., Feddema, D., and Fischer, C.: CCSM4.0 User's Guide, available at: <a href="http://www.cesm.ucar.edu/models/ccsm4.0/ccsm_doc/book1.html">http://www.cesm.ucar.edu/models/ccsm4.0/ccsm_doc/book1.html</a> (last access: 15 January 2014), 2010. Von Salzen, K., Leighton, H., Ariya, P., Barrie, L., Gong, S., Blanchet, J.-P., Spacek, L., Lohmann, U., and Kleinman, L.: Sensitivity of sulphate aerosol size distributions and CCN concentrations over North America to SO<i><sub>x</sub></i> emissions and H<sub>2</sub>O<sub>2</sub> concentrations, J. Geophys. Res.-Atmos., 105, 9741–9765, 2000. Wai, K., Lin, N.-H., Wang, S.-H., and Dokiya, Y.: Rainwater chemistry at a high-altitude station, Mt. Lulin, Taiwan: Comparison with a background station, Mt. Fuji, J. Geophys. Res.-Atmos., 113, D06305, <a href="http://dx.doi.org/10.1029/2006JD008248">https://doi.org/10.1029/2006JD008248</a>, 2008. Weingartner, E., Nyecki, S., and Baltensberger, U.: Seasonal and diurnal variation of aerosol size distributions (10<<i>D</i><750 nm) at a high-alpine site (Jungfraujoch 3580 m asl), J. Geophys. Res., 104, 26809–26820, 1999. Weller, R., Minikin, A., Wagenbach, D., and Dreiling, V.: Characterization of the inter-annual, seasonal, and diurnal variations of condensation particle concentrations at Neumayer, Antarctica, Atmos. Chem. Phys., 11, 13243–13257, <a href="http://dx.doi.org/10.5194/acp-11-13243-2011">https://doi.org/10.5194/acp-11-13243-2011</a>, 2011. Yli-Juuti, T., Nieminen, T., Hirsikko, A., Aalto, P. P., Asmi, E., Hõrrak, U., Manninen, H. E., Patokoski, J., Dal Maso, M., Petäjä, T., Rinne, J., Kulmala, M., and Riipinen, I.: Growth rates of nucleation mode particles in Hyytiälä during 2003–2009: variation with particle size, season, data analysis method and ambient conditions, Atmos. Chem. Phys., 11, 12865–12886, <a href="http://dx.doi.org/10.5194/acp-11-12865-2011">https://doi.org/10.5194/acp-11-12865-2011</a>, 2011. Yu, F., Wang, Z., Luo, G., and Turco, R.: Ion-mediated nucleation as an important global source of tropospheric aerosols, Atmos. Chem. Phys., 8, 2537–2554, <a href="http://dx.doi.org/10.5194/acp-8-2537-2008">https://doi.org/10.5194/acp-8-2537-2008</a>, 2008. Zhang, K., O'Donnell, D., Kazil, J., Stier, P., Kinne, S., Lohmann, U., Ferrachat, S., Croft, B., Quaas, J., Wan, H., Rast, S., and Feichter, J.: The global aerosol-climate model ECHAM-HAM, version 2: sensitivity to improvements in process representations, Atmos. Chem. Phys., 12, 8911–8949, <a href="http://dx.doi.org/10.5194/acp-12-8911-2012">https://doi.org/10.5194/acp-12-8911-2012</a>, 2012. Ziemba, L., Griffin, R., and Talbot, R.: Observations of elevated particle number concentration events at a rural site in New England, J. Geophys. Res.-Atmos., 111, D23S34, <a href="http://dx.doi.org/10.1029/2006JD007607">https://doi.org/10.1029/2006JD007607</a>, 2006. Zíková, N. and Ždímal, V.: Long-term measurement of aerosol number size distributions at rural background station Košetice, Aerosol Air Qual. Res., 13, 1464–1474, <a href="http://dx.doi.org/10.4209/aaqr.2013.02.0056">https://doi.org/10.4209/aaqr.2013.02.0056</a>, 2013.