REPORT SERIES IN AEROSOL SCIENCE N:o 102 (2009) Proceedings of the Finnish Center of Excellence and Graduate School in “Physics, Chemistry, Biology and Meteorology of Atmospheric Composition and Climate Change” Annual Workshop 27.–29.4.2009 Editors: Markku Kulmala, Jaana Bäck, Tuomo Nieminen, and Antti Lauri Yliopistopaino 2009 ISSN 0784-3496 ISBN 978-952-5822-02-1 CONTENTS Kulmala M., Bäck J., Lauri A., Hari P., Kerminen V.-M., Laaksonen A., Nikinmaa E., Riekkola M.-L., Vesala T., and Viisanen Y. Finnish centre of excellence in physics, chemistry, biology and meteorology of atmospheric composition and climate change: overview on activities in 2008 .................................................................................................................................. 13 Lauri A., Bäck J., Vesala T., and Kulmala M. Past, present and future of the Finnish Graduate School on physics, chemistry, biology and meteorology of atmospheric composition and climate change .................................................................................................................................. 29 Reissell A., and Nyman M. iLEAPS, the Land Ecosystem - Atmosphere Processes Study: international cutting- edge research .................................................................................................................................. 34 ABSTRACTS Aaltonen H., Pumpanen J., Pihlatie M., Hakola H., Hellén H., and Bäck, J. Emissions of biogenic volatile organic compounds from boreal scots pine forest floor .................................................................................................................................. 43 Aaltonen H., Heinonsalo J., Pumpanen J., Hellén H., Kajos M., Taipale R., and Bäck J. Emissions of volatile organic compounds from selected fungal species occurring in boreal forest soils .................................................................................................................................. 48 Aaltonen V., de Leeuw G., Arola A., Ginzburg M., and Kulmala M. Diurnal variation of AOD at an Antarctic coastal site .................................................................................................................................. 54 Alam S. A., Starr M., and Nikinmaa E. Carbon sequestration and water-use of agroforestry systems across the Sudanese gum belt .................................................................................................................................. 58 Asmi E., Virkkula A., Ehn M., Frey A., Hillamo R., and Kulmala M. Measured ultrfine aerosol particle hygroscopic growth factors during particle formation and subsequent growth in Antarctica .................................................................................................................................. 64 Bergman T., Makkonen R., Kokkola H., Kerminen V.-M., and Kulmala M. Comparison of two microphysical models in Earth system modeling framework .................................................................................................................................. 68 Boy M., Sogachev A., Smolander S., Lauros J., Vuollekoski H., Sihto S.-L., Suni T., Laakso L., Guenther A., and Kulmala M. New particle formation in rural areas - what we know and what's still mysterious .................................................................................................................................. 71 Brus D., Hyvärinen A.-P., Lihavainen H., and Kulmala M. Binary homogeneous nucleation of H2SO4-H2O .................................................................................................................................. 74 Bäck J., Kolari P., Aalto J., Taipale R., Kajos M., Hari P., and Kulmala M. Comparison of VOC emissions from two Scots pine shoots with a dynamic shoot chamber .................................................................................................................................. 78 Carbone S., Aurela M., Saarikoski S., Kulmala M., Worsnop D., and Hillamo R. Sources of ambient fine particles in Helsinki during winter .................................................................................................................................. 82 Chung C. E., Ramanathan V., Carmichael G., Tang Y., Adhikary B., Leung L. R., and Qian Y. Anthropogenic aerosol radiative forcing in Asia derived from regional models with atmospheric and aerosol data assimilation .................................................................................................................................. 86 Dal Maso M., Hohaus Th., Kiendler-Scharr A., Kleist E., Mentel Th. F., Tillmann R., Liao L., and Wildt J. Factors characterizing the formation efficiency of aerosols from biogenic volatile organic compounds .................................................................................................................................. 91 Ehn M., Petäjä T., Aalto P., Vana M., Vuollekoski H., Ceburnis D., De Leeuw G., O’Dowd C., and Kulmala M. Growth rates during coastal new particle formation at Mace Head, Ireland .................................................................................................................................. 94 Eresmaa N., Härkönen J., Kangas L., and Karppinen A. Comparison of measured and modeled boundary layer heights in Helsinki .................................................................................................................................. 100 Franchin A. Relation between 222Rn concentration and ion production rate in boreal forest .................................................................................................................................. 105 Gagné S., Kurtén T., Nieminen T., Boy M., Petäjä T., Laakso L., and Kulmala M. Factors influencing on the contribution of ion-induced nucleation as a nucleation mechanism in a boreal forest site, Hyytiälä, Finland .................................................................................................................................. 109 Haapanala S., Hakola H., Hellén H., Vestenius M., and Rinne J. VOC emissions of forest felling .................................................................................................................................. 113 Hakala J., Petäjä T., Ehn M., Sipilä M., Junninen H., Vanhanen J., Mikkilä J., and Kulmala M. Monitoring the formation of sulphuric acid clusters in a laminar flow tube using an atmospheric pressure interface time of flight mass spectrometer .................................................................................................................................. 118 Hamed A., Joutsensaari J., Mikkonen S., Wehner B., Birmili W., Tuch T., Spindler G., Wiedensohler A., Decesari S., Mircea M., Fuzzi S., Facchini M. C., and A. Laaksonen Nucleation events in a polluted continental boundary layer as a source of CCN .................................................................................................................................. 121 Hao L. Q., Yli-Pirilä P., Tiitta P., Romakkaniemi S., Vaattovaara P., Kajos M. K., Rinne J., Heijari J., Kortelainen A., Miettinen P., Kroll J. H., Holopainen J.-K., Joutsensaari J., Kulmala M., Worsnop D. R., and Laaksonen A. Secondary organic aerosol from oxidation of real pine emissions .................................................................................................................................. 125 Herrmann E., Hyvärinen A.-P., Brus D., and Kulmala M. Unary and binary nucleation simulations with FLUENT-FPM .................................................................................................................................. 131 Hienola A. I., Hamed A., Nieminen T., Paasonen P., Vuollekoski H., Sihto S.-L., Riipinen I., Sogatcheva L., Kulmala M., and Laaksonen A. Aerosol formation and seasonal variation of related parameters in five European sites .................................................................................................................................. 135 Hilasvuori E., Kolari P., Oinonen M., and Hari P. Carbon isotope fractionation in Scots pine photosynthesis .................................................................................................................................. 141 Hyvärinen A.-P., Wedekind J., Brus D., and Lihavainen H. The "pressure-effect" in unary condensation of n-alcohols .................................................................................................................................. 145 Hölttä T., and Kolari P. Interpretation of stem CO2 efflux .................................................................................................................................. 149 Jaatinen A., Hamed A., Joutsensaari J., Mikkonen S., Birmili W., Wehner B., Spindler G., Wiedensohler A., Decesari S., Mircea M., Facchini M. C., Junninen H., Kulmala, M., Lehtinen K. E. J., and Laaksonen A. The applicability of three different nucleation event day prediction methods at three measurement sites in Europe .................................................................................................................................. 151 Julin J., Napari I., Merikanto J., and Vehkamäki H. A thermodynamically consistent determination of surface tension of small Lennard- Jones clusters from simulation and theory .................................................................................................................................. 156 Järvi L., Rannik Ü, Mammarella I., Sogachev A.,