Groundwater is a vital source of freshwater in Africa where rainfall and river discharge are among the most variable in the planet. Groundwater is widely considered a distributed, low-cost and climate-resilient option to meet rapidly growing freshwater demand in Africa associated with expanding access to safe water and enhancing food security through irrigation. Groundwater storage in Africa is estimated to be ~100 times greater than annual river discharge yet major uncertainties remain about the magnitude and nature of replenishment through recharge as well as the impacts of changes in land cover and climate on surface-groundwater interactions and terrestrial water balances.
Long-term observations of groundwater levels constitute the most direct and robust evidence of volume changes in aquifer systems. Synoptic surveys and long-term monitoring provide rich datasets that enable direct assessments of past impacts of climate variability (e.g. El Niño Southern Oscillation), groundwater abstraction, as well as changes in land-cover and climate. Such records, when continuously updated, also provide key input to water resources management by tracking emerging risks to water security from groundwater storage decline or groundwater flooding. Finally, they are also critical for assessing the reliability of groundwater and land-surface models used to assess projected changes in climate, land cover, and groundwater withdrawals on exploited aquifers at a variety of scales.
Special issue of Hydrogeology Journal: Observed Storage Changes in African Aquifers and their Implications for Sustainable Water Resources Management
We invite submissions that examine evidence from long-term groundwater-level observations (i.e. chronicles) in Africa assessing the impacts on groundwater storage of abstraction, climate variability/change, and land-cover change. We particularly welcome submissions from international teams working on chronicles from the transboundary aquifer systems or basins in Africa. Further, we strongly encourage potential submissions from scientists who may hold or be aware of chronicles in Africa or would like assistance in their analysis.
The special issue of Hydrogeology Journal is an initiative of The Chronicles Consortium, a collaborative endeavour of the African Groundwater Network (AGW-Net), IAH Commission on Groundwater and Climate Change, and UNESCO-IHP GRAPHIC programme. The Chronicles Consortium was established at the 41st Congress of the IAH in Marrakech, Morocco and is led by Tamiru Abiye (Wits University, South Africa), Guillaume Favreau (IRD, France), and Richard Taylor (University College London, UK).