Developing a highresolution Water Balance Model for Africa

Freshwater availability at and near the Earth’s surface is essential for sustaining human societies and ecosystems. However, predicting how water resources will evolve under the variable spatial and temporal patterns of global climate change remains a significant challenge. This challenge is further exacerbated by increasing human pressures on water resources due to population growth and economic development. The situation is particularly dire in regions already facing water scarcity, limited water management infrastructure, and insufficient data—such as much of the African continent, home to approximately 1.5 billion people and many of the world’s least developed countries.A critical aspect of this challenge is our limited understanding of how climatic and anthropogenic forces translate into changes in freshwater fluxes and storage. These responses in the hydrological cycle are generally nonlinear and nonlocal, varying across different timescales. Accurately capturing these dynamics requires a modeling approach that includes all main fluxes and stores across the landscape. Unfortunately, large-scale hydrological models often fail to faithfully represent these processes.To address this, I propose the development of a state-of-the-art, parsimonious hydrological model at the continental scale for Africa. This high-resolution (1 km) model will accurately represent the influence of climate on all hydrological components, enabling analysis at relevant spatial and temporal scales. By improving our understanding of groundwater-surface water interactions and their impact on water availability, the model will support analyses of future climate and water demand scenarios. These insights can be translated into actionable plans and policies to adapt to and mitigate the impacts of evolving water resources and climatic hazards across Africa.