Abrupt change in tropical African climate linked to the bipolar seesaw over the past 55,000 years

E. T. Brown, T. C. Johnson, Christopher A Scholz, A. S. Cohen, J. W. King

Research output: Contribution to journalArticle

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Abstract

The tropics play a major role in global climate dynamics, and are vulnerable to future climate change. We present a record of East African climate since 55 ka, preserved in Lake Malawi sediments, that indicates rapid shifts between discrete climate modes related to abrupt warming (D-O) events observed in Greenland. Although the timing of the Malawi events cannot be determined exactly, our age model implies that they occur prior to their Greenland counterparts, consistent with southward excursions of the Intertropical Convergence Zone during Greenland stadials. The magnitude of each of the events recorded in Malawi sediments corresponds to the scale of the subsequent Greenland warming. This suggests that a tropical component of climate sets a template for abrupt high northern latitude climate fluctuations associated with the bipolar seesaw.

Original languageEnglish (US)
Article numberL20702
JournalGeophysical Research Letters
Volume34
Issue number20
DOIs
StatePublished - Oct 28 2007

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Malawi
Greenland
climate
warming
sediments
intertropical convergence zone
heating
lacustrine deposit
global climate
climate change
tropical regions
lakes
templates
time measurement
sediment
shift

ASJC Scopus subject areas

  • Earth and Planetary Sciences (miscellaneous)

Cite this

Abrupt change in tropical African climate linked to the bipolar seesaw over the past 55,000 years. / Brown, E. T.; Johnson, T. C.; Scholz, Christopher A; Cohen, A. S.; King, J. W.

In: Geophysical Research Letters, Vol. 34, No. 20, L20702, 28.10.2007.

Research output: Contribution to journalArticle

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