Macro-scale water scarcity requires micro-scale approaches. Aspects of vulnerability in semi-arid development.

This paper shows that water scarcity is a complex problem when it affects countries with a semi‐arid climate, ie countries for which there are fluctuations between a dry season and a season when rain occurs. The paper discusses the general vulnerability of the semi‐arid zone in terms of four different types of water scarcity, the effects of which are being superimposed on each other: two are natural (type A, arid climate, type B, intermittent drought years) and two are man‐induced (type C, desiccation of the landscape driven by land degradation, and type D, population‐driven water stress). When fuelled by a rapid population increase, a risk spiral develops, manifesting itself in social and economic collapse during intermittent drought years. The paper concludes that many countries in Africa are heading for severe water scarcity ‐in fact two‐thirds of the African population will live in severely water‐stressed countries within a few decades. This severe water stress will largely be the result of unfettered population growth.