Abstract
Abundant data from paleoenvironmental studies show that the pluviometric evolution for the last 20,000 years is always more gradual and diversified in the northern than in the southern Sahara. Such a pattern is also noted from climatic measurements on the scale of the last century. On both time-scales, two types of abrupt events are much better defined in the pluviometric records of the southern fringe of the Sahara, fast acceleration of the longterm tendency and strong but brief oscillations. Oscillations are probably amplified by the high sensitivity of the monsoon rains to changes in the global climatic equilibrium or to random changes of surface water temperatures in the Atlantic Ocean. The northern boundary, on the contrary, appears to react more gradually and in a variety of ways to the fluctuations of the cyclonic trajectories.
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© 1987 D. Reidel Publishing Company, Dordrecht, Holland
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Rognon, P. (1987). Aridification and Abrupt Climatic Events on the Saharan Northern and Southern Margins, 20,000 Y Bp to Present. In: Berger, W.H., Labeyrie, L.D. (eds) Abrupt Climatic Change. NATO ASI Series, vol 216. Springer, Dordrecht. https://doi.org/10.1007/978-94-009-3993-6_20
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DOI: https://doi.org/10.1007/978-94-009-3993-6_20
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