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Journal of Earth System Science

, Volume 116, Issue 3, pp 171–177 | Cite as

Climatic forcing before, during, and after the 8.2 Kyr B.P. global cooling event

  • Devendra Lal
  • William G. Large
  • Stephan G. Walker
Open Access
Article

Abstract

This paper attempts at full characterization of the unique global 8.2 Kyr B.P. cooling event. Significant atmospheric cooling started during 9.5–8.5 Kyr B.P. when the Sun was extremely quiet during three periods of ∼ 50–100 years. The flood of melt water in the N. Atlantic from glacial lakes during the demise of the Laurentide ice sheet, starting at ∼ 8.5 Kyr B.P., adds to the atmospheric cooling. Climatic forcing events occurred at 8.5 Kyr B.P., at 8.2 Kyr B.P. and finally at 8.06 Kyr B.P., leading to concurrent increases or decreases in the atmospheric Δ14C levels, completely consistent with the climatic forcing proposed here.

Keywords

8.2 Kyr cooling event paleoclimate atmospheric 14atmospheric δ18enhanced oceanic mixing cosmogenic 14C in ice atmospheric sciences climate modeling 

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Copyright information

© Indian Academy of Sciences 2007

Authors and Affiliations

  • Devendra Lal
    • 1
  • William G. Large
    • 2
  • Stephan G. Walker
    • 1
  1. 1.Scripps Institution of OceanographyLa JollaUSA
  2. 2.National Center for Atmospheric ResearchBoulder, ColoradoUSA

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