Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 7 6 2007 10.5194/acpd-7-15341-2007 http://www.atmos-chem-phys-discuss.net/7/15341/2007/ http://www.atmos-chem-phys-discuss.net/7/15341/2007/acpd-7-15341-2007.html http://www.atmos-chem-phys-discuss.net/7/15341/2007/acpd-7-15341-2007.pdf 15341 15372 2007-11-01 Modeling cosmogenic radionuclides ¹⁰Be and ⁷Be during the Maunder Minimum using the ECHAM5-HAM General Circulation Model U. Heikkilä ulla.heikkilae@eawag.ch J. Beer J. Feichter EAWAG, Dübendorf, Switzerland Max-Planck Institute for Meteorology, Hamburg, Germany All existing ¹⁰Be records from Greenland and Antarctica show increasing concentrations during the Maunder Minimum period (MM), 1645–1715, when solar activity was very low and the climate was colder (little ice age). In detail, however, the ¹⁰Be records deviate from each other. We investigate to what extent climatic changes influence the ¹⁰Be measured in ice by modeling this period using the ECHAM5-HAM general circulation model. Production calculations show that during the MM the mean global ¹⁰Be production was higher by 32% than at present due to lower solar activity. Our modeling shows that the zonally averaged modeled ¹⁰Be deposition flux deviates by only ~8% from the average increase of 32%, indicating that climatic effects are much smaller than the production change. Due to increased stratospheric production, the ¹⁰Be content in the downward fluxes is larger during MM, leading to larger ¹⁰Be deposition fluxes in the subtropics, where stratosphere-troposphere exchange (STE) is strongest. In polar regions the effect is small. In Greenland the deposition change depends on latitude and altitude. In Antarctica the change is larger in the east than in the west. We use the ¹⁰Be/⁷Be ratio to study changes in STE. We find larger change between 20° N–40° N during spring, pointing to a stronger STE in the Northern Hemisphere during MM. In the Southern Hemisphere the change is small. These findings indicate that climate changes do influence the ¹⁰Be deposition fluxes, but not enough to significantly disturb the production signal. Climate-induced changes remain small, especially in polar regions. Bard, E., Raisbeck, G., Yiou, F., and Jouzel, J.: Solar modulation of cosmogenic nuclide production over the last millennium: comparison between $^14$C and $^10$Be records, Earth Planet. Sci. Lett., 150, 453–462, 1997. Baskaran, M., Coleman, C., and Santchi, P.: Atmospheric depositional fluxes of $^7$Be and $^210$Pb at Galveston and College Station, Texas, J. Geophys. Res., 98, 20 555–20 571, 1993. Beer, J., Siegenthaler, U., and Blinov, A.: Temporal $^10$Be variations in ice: Information on solar activity and geomagnetic mfield intensity, in: Secular Solar and Geomagnetic Variations in the Last 10,000 Years, Kluwer Academic Publishers, 297–313, 1988. Beer, J., Blinov, A., Bonani, G., Finkel, R. C., Hofmann, H. J., Lehmann, B., Oeschger, H., Sigg, A., Schwander, J., Staffelbach, T., Stauffer, B., Suter, M., and Wölfli, W.: Use of $^10$Be in polar ice to tracer the 11-year cycle of solar activity, Letters to Nature, 347, 164–166, 1990. Brown, L., Stensland, G. J., Klein, J., and Middleton, R.: Atmospheric deposition of $^7$Be and $^10$Be, Geochimica et Cosmochimica Acta, 53, 135–142, 1988. Crowley, T.: Causes of Climate Change Over the Past 1000 Years, Science, 289, 270–277, 2000. Dibb, J. E., Talbot, R. W., Lefer, B. L., Scheuer, E., Gregory, G. L., Browell, E. V., Bradshaw, J. D., Sandholm, S. T., and Singh, H. B.: Distributions of beryllium 7 and lead 210, and soluble aerosol-associated ionic species over the western Pacific: PEM West B, February–March 1994, J. Geophys. Res., 102, 28 287–28 302, 1997. Feichter, J., Roeckner, E., Lohmann, U., and Liepert, B.: Nonlinear aspects of the climate response to greenhouse gas and aerosol forcing, J. Climate, 17(12), 2384–2398, 2004. Field, C., Schmidt, G., Koch, D., and Salyk, C.: Modeling production and climate-related impacts on $^10$Be concentration in ice cores, J. Geophys. Res., 111, D15107, doi:10.1029/2005JD00640, 2006. Gonzalez-Rouco, J. F., Zorita, E., Cubasch, U., von Storch, H., Fischer–Bruns, I., Valero, F., Montavez, J. P., Schlese, U., and Legutke, S.: Simulating the climate since 1000 AD with the AOGCM ECHO–G, In: Proceedings of the ISCS1 2003 symposium `Solar Variability as an Input to the Earth's Environment', Tatranská Lomnica, Slovakia, ESA SP–535, 329–338, 23–28 June 2003. Graham, I., Ditchburn, R., and Barry, B.: Atmospheric deposition of $^7$Be and $^10$Be in New Zealand rain (1996–1998), Geochimica et Cosmochimica Acta, 67, 361–373, 2003. % Igarashi, Y., Hirose, K., and Otsuji-Hatori, M.: Beryllium-7 deposition and its relation to sulfate deposition, J. Atmos. Chem., 29, 217–231, 1998. Jordan, C. E., Dibb, J. E., and Finkel, R. C.: $^10$Be/$^7$Be tracer of atmospheric transport and stratosphere-troposphere exchange, J. Geophys. Res., 108(D8), 4234, doi:10.1029/2002JD002395, 2003. Koch, D., Jacob, D., and Graustein, W.: Vertical transport of tropospheric aerosols as indicated by $^7$Be and $^210$Pb in a chemical tracer model, J. Geophys. Res., 101, 18 651–18 666, 1996. Koch, D. and Rind, D.: Beryllium-10/Beryllium-7 as a tracer of stratospheric transport, J. Geophys. Res., 103, 3907–3917, 1998. Kolb, W.: Aktivitätskonzentrationen von Radionukliden in der bodennahen Luft Norddeutschlands und Nordnorwegens im Zeitraum von 1963 bis 1990, Report PTB-Ra-29, Physikalisch Technische Bundesanstalt, Braunschweig, Germany, 129 pp, 1992. Kollár, D., Leya, I., Masarik, J., and Michel, R.: Calculation of cosmogenic nuclide production rates in Earth's atmosphere and in terrestial surface rocks using improved neutron cross sections, Meteoritics, 35, A90–A91, 2000. Lal, D. and Peters, B.: Cosmic ray produced radioactivity on the Earth, Handbuch der Physik, XLVI/2, 551–612, Springer-Verlag, New York, 1967. Lal, D.: $^10$Be in polar ice: Data reflect changes in cosmic ray flux or polar meteorology, Geophys. Res. Lett., 14, 785–788, 1987. Land, C. and Feichter, J.: Stratosphere-troposphere exchange in a changing climate simulated with the general circulation model MAECHAM4, J. Geophys. Res., 108(D12), 8523, doi:10.1029/2002JD002543, 2003. Langematz, U., Claussnitzer, A., Matthes, K., and Kunze, M.: The climate during the Maunder Minimum: a simulation with the Freie Universität Berlin Climate Middle Atmosphere Model (FUB–CMAM), J. Atmos. Solar-Terr. Phys., 67, 55–60, 2005. Luterbacher, J.: Climate reconstruction and synoptic analysis of the Late Maunder Minimum (AD 1675–1715) period, PhD Thesis, University of Bern, 1999. Masarik. J. and Beer, J.: Simulation of particle fluxes and cosmogenic nuclide production in the Earth's atmosphere, J. Geophys. Res., 104, 12 099–12 111, 1999. McCracken, K., McDonald, F., Beer, J., Raisbeck, G., and Yiou, F.: A phenomenological study of the long-term cosmic ray modulation, 850–1958 AD, J. Geophys. Res., 109, A12103, doi:1029/2005JA10685, 2004. McNeary, D. and Baskaran, M.: Depositional charasteristics of $^7$Be and $^210$Pb in southeastern Michigan, J. Geophys. Res., 108(D7), 4210, doi:10.1029/2002JD00321, 2003. Monaghan, M. C., Krishnaswami, S., and Turekian, K. K.: The global–average production of $^10$Be, Earth Planet. Sci. Lett., 76, 279–287, 1985/1986. Muscheler, R., Joos, F., Beer, J., Müller S, Vonmoos, M., and Snowball, I.: Solar activity during the last 1000 yr inferred from radionuclide records, Quart. Sci. Rev., 26, 82–97, 2007. Raisbeck, G. M., Yiou, F., Fruneau, M., Lieuvin, M., and Loiseaux, J. M.: Measurement of $^10$Be in 1,000– and 5,000-year-old Antarctic ice, Nature, 275, 731–733, 1978. Raisbeck, G. M., Yiou, F., Jouzel, J., and Petit, J. R.: $^10$Be and $\delta^2$H in polar ice cores as a probe of solar variability's influence on climate, Phil. Trans. R. Soc. Lond., A 330, 463–470, 1990. Rehfeld, S. and Heimann, M.: Three dimensional atmospheric transport simulation of the radioactive tracers $^210$Pb, $^7$Be, $^10$Be and $^90$Sr, J. Geophys. Res., 100, 26 141–26 161, 1995. Roeckner, E., Baeuml, G., Bonventura, L., Brokopf, R., Esch, M., Giorgetta, M., Hagemann, S., Kirchner, I., Kornblueh, L., Manzini, E., Rhodin, A., Schlese, U., Schulzweida, U., and Tompkins, A.: The atmospheric general circulation model ECHAM5. PART I: Model description, Report 349, Max Planck Institute for Meteorology, Hamburg, Germany, available from http://www.mpimet.mpg.de, 2003. Stanzick, A.: Räumliche und zeitliche Depositionsvariationen der Radioisotope $^10$Be und $^210$Pb in Eisbohrkernen Zentralgrönlands, Diploma thesis, University of Heidelberg, 1996. Stier, P., Feichter, J., Kinne, S., Kloster, S., Vignati, E., Wilson, J., Ganzeveld., L., Tegen, I., Werner, M., Schulz, M., Balkanski, Y., Boucher, O., Minikin, A., and Petzold, A.: The aerosol–climate model ECHAM5-HAM, Atmos. Chem. Phys., 5, 1125–1165, 2005. Stohl, A., Bonasoni, P., Cristofanelli, P., Collins, W., Feichter, J., Frank, A., Forster, C., Gerasopoulos, E., Gäggeler, H., James, P., Kentarchos, T., Kromp-Kolb, H., Krüger, B., Land, C., Meloen, J., Papayannis, A., Priller, A., Seibert, P., Sprenger, M., Roelofs, G. J., Scheel, H. E., Schnabel, C., Siegmund, P., Tobler, L., Trickl, T., Wernli, H., Wirth, V., Zanis, P., and Zerefos, C.: Stratosphere-troposphere exchange: A review, and what we have learnt from STACCATO, J. Geophys. Res., 108(D12), 8516, doi:10.1029/2002JD002490, 2003. Timmreck, C., Graf, H.-F., and Feichter, J.: Simulation of Mt. Pinatubo volcanic aerosol with the Hamburg Climate Model ECHAM4, Theor. Appl. Climatol., 62, 85–108, 1999. Usoskin, I. G., Alanko–Huotari, K., Kovaltsov, G. A., and Mursula, K.: Heliospheric modulation of cosmic rays: Monthly reconstruction of 1951–2004, J. Geophys. Res., 110, A12108, doi:10.1029/2005JA011250, 2005. Vonmoos, M., Beer, J., and Muscheler, R.: Large variations in Holocene solar activity: Constraints from $^10$Be in the Greenland Ice Core Project ice core, J. Geophys. Res., 111, A10105, doi:10.1029/2005JA011500, 2006. Winiger, P., Huber, O., Halter, J., and Michaud, B.: Konzentrationsmessungen von Be-7, Cs-137 und jungen Spaltfragmenten an der Tropopause, Tellus, 28, 434–441, 1976. Yang, S., Odah, H., and Shaw, J.: Variations in the geomagnetic dipole moment over the last 12 000 years, Geophys. J. Int., 140, 158–162, 2000. Zorita, E., Gonzalez–Rouco, J. F., von Storch, H., Montavez, J. P., and Valero, F.: Natural and anthropogenic model of surface temperature variations in the last thousand years, J. Geophys. Res., 32, L08707, doi:10.1029/2004GL021563, 2005.