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Department of Earth Sciences

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Publication details

Baldini, J.U.L., McDermott, F. & Fairchild, I.J. (2002). Structure of the 8200-year cold event revealed by a speleothem trace element record. Science 296(5576): 2203-2206.

Author(s) from Durham

Abstract

Abrupt first-order shifts in strontium and phosphorus concentrations in stalagmite calcite deposited in western Ireland during the 8200-year event (the major cooling episode 8200 years before the
present) are interpreted as responses to a drier climate lasting about 37 years. Both shifts are centered on 8330 80 years before the present, coinciding with a large oxygen isotope anomaly and a change in the calcite petrography. In this very high resolution (monthly) record, antipathetic second-order oscillations in phosphorus and strontium reveal decreased growth rates and increased rainfall seasonality. Growth rate variations within the event reveal a two-pronged structure consistent with recent model simulations.

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