ACPD Atmospheric Chemistry and Physics Discussions ACPD 1680-7375 Copernicus GmbH Göttingen, Germany 10.5194/acpd-11-9133-2011 Modelling atmospheric OH-reactivity in a boreal forest ecosystem Mogensen D. 1 Smolander S. 1 Sogachev A. 2 Zhou L. 1 Sinha V. 3 4 Guenther A. 5 Williams J. 3 Nieminen T. 1 Kajos M. 1 Rinne J. 1 Kulmala M. 1 Boy M. 1 Division of Atmospheric Sciences, Department of Physics, P.O. Box 48, University of Helsinki, 00014, Finland Wind Energy Division, Risø National Laboratory for Sustainable Energy, Technical University of Denmark, Building 118, Box 49, 4000, Roskilde, Denmark Max Planck Institute of Chemistry, J. Becher Weg 27, 55128 Mainz, Germany Indian Institute of Science Education and Research (IISER) Mohali, MGSIPAP Complex, Sector 26, Chandigarh 160019, India National Center for Atmospheric Research, Boulder, CO 80307, USA 17 03 2011 11 3 9133 9163 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-discuss.net/11/9133/2011/acpd-11-9133-2011.html The full text article is available as a PDF file from http://www.atmos-chem-phys-discuss.net/11/9133/2011/acpd-11-9133-2011.pdf

We have modelled the total atmospheric OH-reactivity in a boreal forest and investigated the individual contributions from gas phase inorganic species, isoprene, monoterpenes, and methane along with other important VOCs. Daily and seasonal variation in OH-reactivity for the year 2008 was examined as well as the vertical OH-reactivity profile. We have used SOSA; a one dimensional vertical chemistry-transport model (Boy et al., 2011) together with measurements from Hyytiälä, SMEAR II station, Southern Finland, conducted in August 2008. Model simulations only account for ~30–50% of the total measured OH sink, and in our opinion, the reason for missing OH-reactivity is due to unmeasured unknown BVOCs, and limitations in our knowledge of atmospheric chemistry including uncertainties in rate constants. Furthermore, we found that the OH-reactivity correlates with both organic and inorganic compounds and increases during summer. The summertime canopy level OH-reactivity peaks during night and the vertical OH-reactivity decreases with height.

 References Apel, E. C., Emmons, L. K., Karl, T., Flocke, F., Hills, A. J., Madronich, S., Lee-Taylor, J., Fried, A., Weibring, P., Walega, J., Richter, D., Tie, X., Mauldin, L., Campos, T., Weinheimer, A., Knapp, D., Sive, B., Kleinman, L., Springston, S., Zaveri, R., Ortega, J., Voss, P., Blake, D., Baker, A., Warneke, C., Welsh-Bon, D., de Gouw, J., Zheng, J., Zhang, R., Rudolph, J., Junkermann, W., and Riemer, D. D.: Chemical evolution of volatile organic compounds in the outflow of the Mexico City Metropolitan area, Atmos. Chem. Phys., 10, 2353–2375, http://dx.doi.org/10.5194/acp-10-2353-2010doi:10.5194/acp-10-2353-2010, 2010. Atkinson, R., Baulch, D. L., Cox, R. A., Hampson Jr., R. F., Kerr, J. A., and Troe, J.: Evaluated kinetic and photochemical data for atmospheric chemistry, Supplement IV, ~ J. Phys. Chem. Ref. Data, 21, 1125–1568, 1992. Boy, M. and Kulmala, M.: The part of the solar spectrum with the highest influence on the formation of SOA in the continental boundary layer, Atmos. Chem. Phys., 2, 375–386, http://dx.doi.org/10.5194/acp-2-375-2002doi:10.5194/acp-2-375-2002, 2002. Boy, M., Rannik, U., Lehtinen, K., Tarvainen, V., Hakola, H., and Kulmala, M.: Nucleation events in the continental pbl long term statistical analysis of aerosol relevant characteristics, J. Geophys. Res., 108, 4667–4679, 2003. Boy, M., Petäjä, T., Dal Maso, M., Rannik, \"U., Rinne, J., Aalto, P., Laaksonen, A., Vaattovaara, P., Joutsensaari, J., Hoffmann, T., Warnke, J., Apostolaki, M., Stephanou, E. G., Tsapakis, M., Kouvarakis, A., Pio, C., Carvalho, A., Römpp, A., Moortgat, G., Spirig, C., Guenther, A., Greenberg, J., Ciccioli, P., and Kulmala, M.: Overview of the field measurement campaign in Hyytiälä, August 2001 in the framework of the EU project OSOA, Atmos. Chem. Phys., 4, 657–678, http://dx.doi.org/10.5194/acp-4-657-2004doi:10.5194/acp-4-657-2004, 2004. Boy, M., Sogachev, A., Lauros, J., Zhou, L., Guenther, A., and Smolander, S.: SOSA – a new model to simulate the concentrations of organic vapours and sulphuric acid inside the ABL - Part 1: Model description and initial evaluation, Atmos. Chem. Phys., 11, 43–51, http://dx.doi.org/10.5194/acp-11-43-2011doi:10.5194/acp-11-43-2011, 2011. Chatani, S., Shimo, N., Matsunaga, S., Kajii, Y., Kato, S., Nakashima, Y., Miyazaki, K., Ishii, K., and Ueno, H.: Sensitivity analyses of OH missing sinks over Tokyo metropolitan area in the summer of 2007, Atmos. Chem. Phys., 9, 8975–8986, http://dx.doi.org/10.5194/acp-9-8975-2009doi:10.5194/acp-9-8975-2009, 2009. Damian, V., Sandu, A., Damian, M., Potra, F., and Carmichael, G. R.: The Kinetic PreProcessor KPP – A software environment for solving chemical kinetics, Comput. Chem. Eng., 26, 1567–1579, 2002. de Gouw, J. and Warneke, C.: Measurements of volatile organic compounds in the earths atmosphere using proton-transfer-reaction mass spectrometry, Mass Spectrom. Rev., 26, 223–257, 2007. Di Carlo, P., Brune, W. H., Martinez, M., Harder, H., Lesher, R., Ren, X., Thornberry, T., Carroll, M. A., Young, V., Shepson, P. B., Riemer, D., Apel, E., and Campbell, C.: Missing OH Reactivity in a Forest: Evidence for Unknown Reactive Biogenic VOCs, Science, 304, 722–725, 2004. Faloona, I., Tan, D., Brune, W., Hurst, J., Barket Jr., D., Couch, T. L., Shepson, P., Apel, E., Riemer, D., Thornberry, T., Carroll, M. A., Sillman, S., Keeler, G. J., Sagady, J., Hooper, D., and Paterson, K.: Nighttime observations of anomalously high levels of hydroxyl radicals above a deciduous forest canopy, J. Geophys. Res., 106, 24315–24333, 2001. Goldstein, A. H., and Galbally, I. E.: Known and Unexplored Organic Constituents in the Earth's Atmosphere, Environ. Sci. Technol., 41, 1514–1521, 2007. 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, http://dx.doi.org/10.5194/acp-6-3181-2006doi:10.5194/acp-6-3181-2006, 2006. Haapanala, S., Rinne, J., Hakola, H., Hell$\acute\rm e$n, H., Laakso, L., Lihavainen, H., Janson, R., O'Dowd, C., and Kulmala, M.: Boundary layer concentrations and landscape scale emissions of volatile organic compounds in early spring, Atmos. Chem. Phys., 7, 1869–1878, http://dx.doi.org/10.5194/acp-7-1869-2007doi:10.5194/acp-7-1869-2007, 2007. Hakola, H., Tarvainen, V., Bäck, J., Ranta, H., Bonn, B., Rinne, J., and Kulmala, M.: Seasonal variation of mono- and sesquiterpene emission rates of Scots pine, Biogeosciences, 3, 93–101, http://dx.doi.org/10.5194/bg-3-93-2006doi:10.5194/bg-3-93-2006, 2006. Hari, P. and Kulmala, M.: Station for measuring ecosystem-atmosphere relations (SMEAR II), Boreal Environ. Res., 10, 315–322, 2005. Hofzumahaus, A., Rohrer, F. Lu, K., Bohn, B., Brauers, T., Chang, C-C., Fuchs, H., Holland, F., Kita, K., Kondo, Y., Li, X., Lou, S., Shao, M., Zeng, L., Wahner, A., and Zhang, Y. Amplified Trace Gas Removal in the Troposphere, Science, 324, 1702–1704, 2009. Holzinger, R., Lee, A., Paw, K. T., and Goldstein, U. A. H.: Observations of oxidation products above a forest imply biogenic emissions of very reactive compounds, Atmos. Chem. Phys., 5, 67–75, http://dx.doi.org/10.5194/acp-5-67-2005doi:10.5194/acp-5-67-2005, 2005. Kiendler-Scharr, A., Wildt, J., Dal Maso, M., Hohaus, T., Kleist, E., Mentel, T. F., Tillmann, R., Uerlings, R., Schurr, U., and Wahner, A.: New particle formation in forests inhibited by isoprene emissions, Nature, 461, 381–384, 2009. Kovacs, T. A. and Brune, W. H.: Total OH loss rate measurement, J. Atmos. Chem., 39, 105–122, 2001. Kovacs, T. A., Brune, W. H., Harder, H., Martinez, M., Simpas, J. B., Frost, G. J., Williams, E., Jobson, R., Stroud, C., Young, V., Fried, A., and Wert, B.: Direct measurements of urban OH reactivity during Nashville SOS in summer 1999, J. Environ. Monit., 5, 68–74, 2003. Kulmala, M., Haemeri, K. K., Aalto, P., Maekelae, J., Pirjola, L., Nilsson, E. D., Buzorius, G., Rannik, U., Dal Maso, M., Seidl, W., Hoffmann, T., Jansson, R., Hansson, H.-C., O'Dowd, C., and Viisanen, Y.: Overview of the international project on biogenic aerosol formation in the boreal forest (BIOFOR), Tellus B, 53, 324–343, 2001. Kurpius, M. R. and Goldstein, A. H.: Gas-phase chemistry dominates O<sub>3</sub> loss to a forest, implying a source of aerosols and hydroxyl radicals to the atmosphere, Geophys. Res. Lett., 30, 1371–1374, 2003. Lou, S., Holland, F., Rohrer, F., Lu, K., Bohn, B., Brauers, T., Chang, C.C., Fuchs, H., Häseler, R., Kita, K., Kondo, Y., Li, X., Shao, M., Zeng, L., Wahner, A., Zhang, Y., Wang, W., and Hofzumahaus, A.: Atmospheric OH reactivities in the Pearl River Delta - China in summer 2006: measurement and model results, Atmos. Chem. Phys., 10, 11243–11260, http://dx.doi.org/10.5194/acp-10-11243-2010doi:10.5194/acp-10-11243-2010, 2010. Mao, J., Ren, X., Brune, W. H., Olson, J. R., Crawford, J. H., Fried, A., Huey, L. G., Cohen, R. C., Heikes, B., Singh, H. B., Blake, D. R., Sachse, G. W., Diskin, G. S., Hall, S. R., and Shetter, R. E.: Airborne measurement of OH reactivity during INTEX-B, Atmos. Chem. Phys., 9, 163–173, http://dx.doi.org/10.5194/acp-9-163-2009doi:10.5194/acp-9-163-2009, 2009. Maris, C., Chung, M. Y., Lueb, R., Krischke, U., Meller, R., Fox, M. J., and Paulson, S. E.: Development of instrumentation for simultaneous analysis of total non-methane organic carbon and volatile organic compounds in ambient air, Atmos. Environ., 37, 149–158, 2003. Martinez, M., Harder, H., Kubistin, D., Rudolf, M., Bozem, H., Eerdekens, G., Fischer, H., Klüpfel, T., Gurk, C., Königstedt, R., Parchatka, U., Schiller, C. L., Stickler, A., Williams, J., and Lelieveld, J.: Hydroxyl radicals in the tropical troposphere over the Suriname rainforest: airborne measurements, Atmos. Chem. Phys., 10, 3759–3773, http://dx.doi.org/10.5194/acp-10-3759-2010doi:10.5194/acp-10-3759-2010, 2010. O'Dowd, C. D., Aalto, P., Hämeri, K., Kulmala, M., and Hoffmann, T.: Aerosol formation: Atmospheric particles from organic vapours, Nature, 416, 497–498, 2002. Ren, X. R., Harder, H., Martinez, M., Lesher, R. L., Oliger, A., Shirley, Y., Adams, J., Simpas, J. B., and Brune, W. H.: HOx concentrations and OH reactivity observations in New York City during PMTACS-NY2001, ~ Atmos. Environ., 37, 3627–3637, 2003. Rinne, J., Ruuskanen, T. M., Reissell, A., Taipale, R., Hakola, H., and Kulmala, M.: On-line PTR-MS measurements of atmospheric concentrations of volatile organic compounds in a European boreal forest ecosystem, Boreal Environ. Res., 10, 425–436, 2005. Rinne, J., Taipale, R., Markkanen, T., Ruuskanen, T. M., Hell$\acute\rm e$n, H., Kajos, M. K., Vesala, T., and Kulmala, M.: Hydrocarbon fluxes above a Scots pine forest canopy: measurements and modeling, Atmos. Chem. Phys., 7, 3361–3372, http://dx.doi.org/10.5194/acp-7-3361-2007doi:10.5194/acp-7-3361-2007, 2007. Rinne, J., Bäck, J., and Hakola, H.: Biogenic volatile organic compound emissions from the Eurasian taiga: current knowledge and future directions, Boreal Environ. Res., 14, 807–826, 2009. Roberts, J. M., Bertman, S. B., Jobson, T., Niki, H., and Tanner, R.: Measurement of total nonmethane organic carbon (C-y): Development and application at Chebogue Point, Nova Scotia, during the 1993 North Atlantic Regional Experiment campaign, J. Geophys. Res.-Atmos., 103, 13581–13597, 1998 Sadanaga, Y., Yoshino, A., Watanabe, K., Yoshioka, A., Wakazono, Y., Kanaya, Y., and Kajii, Y.: Development of a measurement system of OH reactivity in the atmosphere by using a laser-induced pump and probe technique., Rev. Sci. Instrum., 75, 2648–2655, 2004. Sadanaga, Y., Yoshino, A., Kato, S., and Kajii, Y.: Measurements of OH Reactivity and Photochemical Ozone Production in the Urban Atmosphere, Environ. Sci. Technol., 39, 8847–8852, 2005. Sinha, V., Williams, J., Crowley, J. N., and Lelieveld, J.: The Comparative Reactivity Method - a new tool to measure total OH Reactivity in ambient air, Atmos. Chem. Phys., 8, 2213–2227, http://dx.doi.org/10.5194/acp-8-2213-2008doi:10.5194/acp-8-2213-2008, 2008. Sinha, V., Custer, T. G., Kluepfel, T., and Williams, J.: The effect of relative humidity on the detection of pyrrole by PTR-MS for OH reactivity measurements, Int. J. Mass. Spectrom., 282, 108–111, 2009. Sinha, V., Williams, J., Lelieveld, J., Ruuskanen, T. M., Kajos, M. K., Patokoski, J., Hellen, H., Hakola, H., Mogensen, D., Boy, M., Rinne, J., and Kulmala, M.: OH Reactivity Measurements within a Boreal forest: Evidence for Unknown Reactive Emissions, Env. Sci. Tech., 44, 6614–6620, 2010. Sogachev, A.: A note on two-equation closure modelling of canopy flow, Bound.-Lay. Meteorol., 130, 423–435, 2009. Sogachev, A. and Panferov, O.: Modification of two-equation models to account for plant drag, Bound.-Lay. Meteorol., 121, 229–266, 2006. Sogachev, A., Menzhulin, G., Heimann, M., and Lloyd, J.: A simple three dimensional canopy planetary boundary layer simulation model for scalar concentrations and fluxes, Tellus B, 54, 784–819, 2002. Sogachev, A., Panferov, O., Gravenhorst, G., and Vesala, T.: Numerical analysis of flux footprints for different landscapes, Theor. Appl. Climatol., 80, 169–185, 2005. Taipale, R., Ruuskanen, T. M., Rinne, J., Kajos, M. K., Hakola, H., Pohja, T., and Kulmala, M.: Technical Note: Quantitative long-term measurements of VOC concentrations by PTR-MS - measurement, calibration, and volume mixing ratio calculation methods, Atmos. Chem. Phys., 8, 6681–6698, http://dx.doi.org/10.5194/acp-8-6681-2008doi:10.5194/acp-8-6681-2008, 2008. Tarvainen, V., Hakola, H., Rinne, J., Helln, H., and Haapanala, S.: Towards a comprehensive emission inventory of terpenoids from boreal ecosystems, Tellus, 59B, 526–534, 2007.