Eolian Evidence for Spatial Variability of Late Quaternary Climates in Tropical Africa

Citeable URL: https://ir.library.oregonstate.edu/concern/articles/jd472z28k

Descriptions

Attribute Name	Values
Creator	Pokras, Edward M. Mix, Alan C.
Abstract	Study of the eolian fraction of late Quaternary sediments from the tropical Atlantic reveals that two modes of long-term climate variability have existed in tropical Africa during the last 150,000 yr. Tropical northwest Africa (i.e., the southwestern Sahara and Sahel) was driest during glaciations and stades, but wetter than at present during interglaciations and interstades. This may be a response to ice sheets at higher latitudes, via equatorward displacement of the westerlies and the subtropical high. In contrast, central equatorial Africa (southeast of the Sahara) was most arid during interstades and times of ice growth, and most humid during deglaciation. Wet periods in this area correspond to insolation maxima in northern hemisphere summer. A 23,000-yr precessional rhythm is suggested, supporting a direct link between African Monsoon intensity and orbitally modulated insolation. The late Holocene is the only time observed when both areas are arid during an interglacial episode. This may reflect, in part, anthropogenic disturbance of late Holocene climates.
Resource Type	Article
DOI	https://doi.org/10.1016/0033-5894(85)90001-8
Date Available	2017-05-01T21:27:08+00:00
Date Issued	2017-05-01
Declaração de direitos	Copyright Not Evaluated
Peer Reviewed	Yes
Language	English [eng]
Replaces	http://hdl.handle.net/1957/60671