Regime Shifts in the Sahara and Sahel: Interactions between Ecological and Climatic Systems in Northern Africa

@article{Foley2002RegimeS,
  title={
Regime Shifts in the Sahara and Sahel: Interactions between Ecological and Climatic Systems in Northern Africa
},
  author={Jonathan A. Foley and Michael T. Coe and Marten Scheffer and Guiling Wang},
  journal={Ecosystems},
  year={2002},
  volume={6},
  pages={524-532}
}
The Sahara and Sahel regions of northern Africa have complex environmental histories punctuated by sudden and dramatic “regime shifts” in climate and ecological conditions. Here we review the current understanding of the causes and consequences of two environmental regime shifts in the Sahara and Sahel. The first regime shift is the sudden transition from vegetated to desert conditions in the Sahara about 5500 years ago. Geologic data show that wet environmental conditions in this region—giving… 

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