Patterns of millennial variability over the last 500 ka

Date

2010

Authors

Siddall, M
Rohling, Eelco
Blunier, T.
Spahni, R.

Journal Title

Journal ISSN

Volume Title

Publisher

Copernicus GmbH

Abstract

Millennial variability is a robust feature of many paleoclimate records, at least throughout the last several glacial cycles. Here we use the mean signal from Antarctic climate events 1 to 4 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 via sea-ice feedbacks and that this relationship is modified by the presence of the large, Northern Hemisphere ice sheets during glacial periods.

Description

Keywords

Keywords: atmospheric circulation; glacial debris; glacial history; glacial-interglacial cycle; ice sheet; iceberg; paleoclimate; sea ice; Antarctica; Dome Concordia; East Antarctica

Citation

Source

Climate of the Past

Type

Journal article

Book Title

Entity type

Access Statement

License Rights

DOI

10.5194/cp-6-295-2010

Restricted until

2037-12-31