Leaf-waxes hydrogen isotopic composition of sediment core GeoB4905-4

  • James A. Collins (Contributor)
  • Matthias Prange (Contributor)
  • Thibaut Caley (Contributor)
  • Luis Gimeno (Contributor)
  • Britta Beckmann (Contributor)
  • Stefan Mulitza (Contributor)
  • Charlotte Skonieczny (Contributor)
  • Didier Roche (Contributor)
  • Enno Schefuss (Contributor)



Abstract: The rapidity and synchrony of the African Humid Period (AHP) termination at around 5.5 ka are debated, and it is unclear what caused a rapid hydroclimate response. Here we analyzed the hydrogen isotopic composition of sedimentary leaf-waxes (dDwax) from the Gulf of Guinea, a proxy for regional precipitation in Cameroon and the central Sahel-Sahara. Our record indicates high precipitation during the AHP followed by a rapid decrease at 5.8-4.7 ka. The similarity with a dDwax record from northern East Africa suggests a large-scale atmospheric mechanism. We show that northern high- and mid-latitude cooling weakened the Tropical Easterly Jet and, through feedbacks, strengthened the African Easterly Jet. The associated decrease in precipitation triggered the AHP termination and combined with biogeophysical feedbacks to result in aridification. Our findings suggest that extratropical temperature changes, albeit smaller than during the glacial and deglacial, were important in triggering rapid African aridification during the Holocene.

Category: geoscientificInformation

Source: Supplement to: Collins, James A; Prange, Matthias; Caley, Thibaut; Gimeno, Luis; Beckmann, Britta; Mulitza, Stefan; Skonieczny, Charlotte; Roche, Didier M; Schefuß, Enno (2017): Rapid termination of the African Humid Period triggered by northern high-latitude cooling. Nature Communications, 8(1), https://doi.org/10.1038/s41467-017-01454-y

Supplemental Information: Not Availble

Coverage: EVENT LABEL: GeoB4905-4 * LATITUDE: 2.500000 * LONGITUDE: 9.390000 * DATE/TIME: 1998-03-01T06:48:00 * ELEVATION: -1328.0 m * Recovery: 12.18 m * LOCATION: off Cameroon * CAMPAIGN: M41/1 * BASIS: Meteor (1986) * METHOD/DEVICE: Gravity corer (Kiel type)
Date made available1 Dec 2017
PublisherUnknown Publisher

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