Managing Current Climate Variability Can Ensure Water Security Under Climate Change

Abstract Water resources will be significantly impacted upon by climate change, and these impacts will be transmitted to the many sectors and services dependent on them. The nature, extent, and timing of these impacts remain uncertain, but the long lifetime of water infrastructures requires that their planning, development, and operations should be resilient to climate changes. An effective approach is to focus on the management of current climate variability as it relates to water, which strengthens the ability of communities and countries to foresee, manage, and adapt to the impacts of longer-term climate change on water-related activities. This approach is illustrated by cases from Southern and Eastern Africa. Current “stationary” stochastic methods of hydrological analysis can still be used under assumptions of a “dynamic stationarity” although more regular updating of hydrological data will be required. Methodologies to evaluate economic dimensions of risk reduction introduce additional uncertainties but may help decision-makers to understand the risks and opportunities. Diversification of sources and sequencing of resource development pathways are helpful strategies to adapt to climate change but must ensure that risks affecting different sources are not correlated. Attention must also be given to demand-side interventions in order to reconcile supply and demand, and these perspectives must be shared with social, economic, and political actors to ensure that strategies are communicated, understood, and supported by the wider community.