Ventilation of the North Atlantic Ocean during the Last Glacial Maximum: A comparison between simulated and observed radiocarbon ages

نویسندگان

  • K. J. Meissner
  • A. Schmittner
  • A. J. Weaver
  • J. F. Adkins
چکیده

[1] The distribution of radiocarbon during simulations of the Last Glacial Maximum with a coupled oceanatmosphere-sea ice model is compared with sediment core measurements from the equatorial Atlantic Ceara Rise, Blake Ridge, Caribbean Sea, and South China Sea. During these simulations we introduce a perturbation of North Atlantic freshwater fluxes leading to varying strengths of the Atlantic meridional overturning. The best fit with the observations is obtained for an overturning weakened by 40% compared with today. Further, we simulate the phenomenon of an ‘‘age reversal’’ found in deep sea corals, but we suggest that this indicates rather a sudden interruption of deep water formation instead of an increase in ventilation, which was suggested earlier.

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تاریخ انتشار 2003