Sub-saharan desertification and productivity are linked to hemispheric climate variability

Vegetation productivity and desertification in sub-Saharan Africa may be in fluenced by global climate variability attributable to the North Atlantic O scillation (NAO) and El Nino Southern Oscillation (ENSO). Combined and indi vidual effects of the NAO and ENSO indices revealed that 75% of the interan nual variation in the area of Sahara Desert was accounted for by the combin ed effects, with most variance attributable to the NAG. Effects were shown in the latitudinal variation on the 200 mm isocline, which was influenced m ostly by the NAG. The combined indices explained much of the interannual va riability in vegetation productivity in the Sahelian zone and southern Afri ca, implying that both the NAO and ENSO may be useful for monitoring effect s of global climate change in sub-Saharan Africa.