Recurrence times for extreme drought events in theAfrican Sahel are estimated using a classical peaks-over-threshold model. Results, which are computed for bothmean seasonal rainfall and fractional area in drought,suggest that the distribution of dry extremes after about1970 is statistically distinct from that of preceding years.This finding throws into relief the critical role played byattribution of causes, and the necessity of improving ourunderstanding of the physical processes driving precipitationvariability in the Sahel
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