Atlantic Forcing of Persistent Drought in West Africa

Publication Type: 
Year of Publication: 
2009
Journal Title: 
Science
Journal Date: 
Apr 17
Volume: 
324
Issue: 
5925
Pages: 
377-380
ISBN Number: 
0036-8075
Accession Number: 
ISI:000265221600039
Abstract: 

Although persistent drought in West Africa is well documented from the instrumental record and has been primarily attributed to changing Atlantic sea surface temperatures, little is known about the length, severity, and origin of drought before the 20th century. We combined geomorphic, isotopic, and geochemical evidence from the sediments of Lake Bosumtwi, Ghana, to reconstruct natural variability in the African monsoon over the past three millennia. We find that intervals of severe drought lasting for periods ranging from decades to centuries are characteristic of the monsoon and are linked to natural variations in Atlantic temperatures. Thus the severe drought of recent decades is not anomalous in the context of the past three millennia, indicating that the monsoon is capable of longer and more severe future droughts.

Notes: 

433QTTimes Cited:1Cited References Count:44

DOI: 
DOI 10.1126/science.1166352