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Patterns of millennial variability over the last 500 ka
M. Siddall1, E. J. Rohling2, T. Blunier3, and R. Spahni4
1Department of Earth Science, University of Bristol, Bristol, UK
2National Oceanography Centre, Southampton, Southampton, UK
3Centre for Ice & Climate, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
4Climate and Environmental Physics and Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
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Abstract. Millennial variability is a robust feature of many
paleoclimate records, at least throughout the last several
glacial cycles. Here we use the signal from an Antarctic
climate event to probe the EPICA Dome C temperature proxy
reconstruction through the last 500 ka for similar
millennial-scale events. We find that clusters of millennial
events occurred in a regular fashion over half of the time
during this with a mean recurrence interval of 21 kyr. We
find that there is no consistent link between ice-rafted
debris deposition and millennial variability. Instead we
speculate that changes in the zonality of atmospheric
circulation over the North Atlantic form a viable alternative
to freshwater release from icebergs as a trigger for
millennial variability. We suggest that millennial changes in
the zonality of atmospheric circulation over the North
Atlantic are linked to precession and that this relationship
is modified by the presence of the large, Northern Hemisphere
ice sheets during glacial periods.
 Notice on Discussion StatusThe requested discussion paper has a corresponding peer-reviewed
final revised paper in the journal Climate of the Past (CP). You are
encouraged to refer to the final revised version. Final Revised Paper (CP) Discussion Paper (PDF, 510 KB)
Citation: Siddall, M., Rohling, E. J., Blunier, T., and Spahni, R.: Patterns of millennial variability over the last 500 ka, Clim. Past Discuss., 6, 19-34, doi:10.5194/cpd-6-19-2010, 2010. Bibtex EndNote Reference Manager XML
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