Changes in deep-water formation during the Younger Dryas event inferred from 10Be and 14C records

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Variations in atmospheric radiocarbon (14C) concentrations can be attributed either to changes in the carbon cycle1—through the rate of radiocarbon removal from the atmosphere—or to variations in the production rate of 14C due to changes in solar activity or the Earth's magnetic field2. The production rates of 10Be and 14C vary in the same way, but whereas atmospheric radiocarbon concentrations are additionally affected by the carbon cycle, 10Be concentrations reflect production rates more directly. A record of the 10Be production-rate variations can therefore be used to separate the two influences—production rates and the carbon cycle—on radiocarbon concentrations. Here we present such an analysis of the large fluctuations in atmospheric 14C concentrations, of unclear origin3, that occurred during the Younger Dryas cold period6. We use the 10Be record from the GISP2 ice core5 to model past production rates of radionuclides, and find that the largest part of the fluctuations in atmospheric radiocarbon concentrations can be attributed to variations in production rate. The residual difference between measured 14C concentrations and those modelled using the 10Be record can be explained with an additional change in the carbon cycle, most probably in the amount of deep-water formation.

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Figure 1: 10Be flux versus δ18O in ice at Summit. δ18O denotes the relative deviation in per mil of the 18O/16O ratio from the 18O/16O value of SMOW (standard mean ocean water).
Figure 2: Comparison of modelled and measured Δ14C from 11,850 to 9,300 yr bp.
Figure 3: Comparison of modelled and measured Δ14C, together with 10Be flux and proxy climate data from 15,000 to 9,300 yr bp.


  1. 1

    Siegenthaler, U., Heimann, M. & Oeschger, H. 14C variations caused by changes in the global carbon cycle. Radiocarbon 22, 177–191 (1980).

  2. 2

    Lal, D. & Peters, B. in Handbuch für Physik (ed. Flügge, S.) 551–612 (Springer, Berlin, 1967).

  3. 3

    Goslar, T., Arnold, M., Tisnerat-Laborde, N., Czernik, J. & Wiȩckowski, K. Variations of Younger Dryas atmospheric radiocarbon explicable without ocean circulation changes. Nature 403, 877–880 (2000).

  4. 4

    Hughen, K. et al. Deglacial changes in ocean circulation from an extended radiocarbon calibration. Nature 391, 65–68 (1998).

  5. 5

    Finkel, R. C. & Nishiizumi, K. Beryllium 10 concentrations in the Greenland Ice Sheet Project 2 ice core from 3-40 ka. J. Geophys. Res. 102, 26699–26706 (1997).

  6. 6

    Goslar, T. et al. High concentration of atmospheric 14C during the Younger Dryas cold episode. Nature 377, 414–417 (1995).

  7. 7

    Björck, S. et al. Synchronized terrestrial-atmospheric deglacial records around the North Atlantic. Science 274, 1155–1160 (1996).

  8. 8

    Stocker, T. F. & Wright, D. G. Rapid changes in ocean circulation and atmospheric radiocarbon. Paleoceanography 11, 773–795 (1996).

  9. 9

    Marchal, O. et al. Modelling the concentration of atmospheric CO2 during the Younger Dryas climate event. Clim. Dyn. 15, 341–354 (1999).

  10. 10

    Stuiver, M. & Polach, H. A. Discussion reporting of 14C data. Radiocarbon 19, 355–363 (1977).

  11. 11

    Beer, J. et al. Information on past solar activity and geomagnetism from 10Be in the Camp Century ice core. Nature 331, 675–679 (1988).

  12. 12

    Masarik, J. & Beer, J. Simulation of particle fluxes and cosmogenic nuclide production in the Earth's atmosphere. J. Geophys. Res. 104, 12099–12111 (1999).

  13. 13

    McHargue, L. R. & Damon, P. E. The global beryllium-10 cycle. Rev. Geophys. 29, 141–158 (1991).

  14. 14

    Broecker, W. S., Peteet, D. M. & Rind, D. Does the ocean–atmosphere system have more than one stable mode of operation? Nature 315, 21–26 (1985).

  15. 15

    Wagner, G. Die kosmogenen Radionuklide 10Be und 36Cl im Summit-GRIP-Eisbohrkern. Thesis, ETH Zürich (1998).

  16. 16

    Wagner, G. et al. Chlorine-36 evidence for the Mono Lake event in the Summit GRIP ice core. Earth Planet. Sci. Lett. 181, 1–6 (2000).

  17. 17

    Johnsen, S. J., Dansgaard, W. & White, J. W. C. The origin of Arctic precipitation under present and glacial conditions. Tellus B 41, 452–468 (1989).

  18. 18

    Charles, C. D., Rind, D., Jouzel, J., Koster, R. D. & Fairbanks, R. G. Glacial-interglacial changes in moisture sources for Greenland: Influences on the ice core record of climate. Science 263, 508–511 (1994).

  19. 19

    Siegenthaler, U. Uptake of excess CO2 by an outcrop-diffusion model of the ocean. J. Geophys. Res. 88, 3599–3608 (1983).

  20. 20

    Stuiver, M. et al. INTCAL98 radiocarbon age calibration, 24,000-0 cal BP. Radiocarbon 40, 1041–1083 (1998).

  21. 21

    Stuiver, M. & Quay, P. D. Changes in atmospheric carbon-14 attributed to a variable sun. Science 207, 11–19 (1980).

  22. 22

    Björck, S. et al. High-resolution analyses of an early Holocene cooling event may imply solar forcing as an important climate trigger. Geology (submitted).

  23. 23

    Alley, R. B. et al. Visual-stratigraphic dating of the GISP2 ice core: Basis, reproducibility, and application. J. Geophys. Res. 102, 26367–26381 (1997).

  24. 24

    Hughen, K. A., Overpeck, J. T., Peterson, L. C. & Trumbore, S. Rapid climate changes in the tropical Atlantic region during the last deglaciation. Nature 380, 51–54 (1996).

  25. 25

    Tauxe, L. Sedimentary records of relative paleointensity of the geomagnetic field: theory and practice. Rev. Geophys. 31, 319–354 (1993).

  26. 26

    Alley, R. B. et al. Changes in continental and sea-salt atmospheric loadings in central Greenland during the most recent deglaciation: model-based estimates. J. Glaciol. 41, 503–514 (1995).

  27. 27

    Johnsen, S. J., Dahl-Jensen, D., Dansgaard, W. & Gundestrup, N. Greenland palaeotemperatures derived from GRIP bore hole temperature and ice core isotope profiles. Tellus B 47, 624–629 (1995).

  28. 28

    Johnsen, S. J. et al. Irregular glacial interstadials recorded in a new Greenland ice core. Nature 359, 311–313 (1992).

  29. 29

    Johnsen, S. J. et al. The δ18O record along the Greenland Ice Core Project deep ice core and the problem of possible Eemian climatic instability. J. Geophys. Res. 102, 26397–26410 (1997).

  30. 30

    Grootes, P. M. & Stuiver, M. Oxygen 18/16 variability in Greenland snow and ice with 10-3- to 105-year time resolution. J. Geophys. Res. 102, 26455–26470 (1997).

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Data were provided by the National Snow and Ice Data Center, University of Colorado at Boulder, and the WDC-A for Paleoclimatology, National Geophysical Data Center, Boulder, Colorado. We thank K. Hughen for the 14C calibration data and the grey scale record of the Cariaco sediments. This work was supported by the Swiss National Science Foundation and the US Department of Energy.

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Correspondence to Raimund Muscheler.

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