CAS-Climate: Understanding the link between regional climate patterns and water supply in the Horn of Africa

In recent decades, recurrent severe droughts in the Horn of Africa (HOA) have led to devastating socio-economic consequences. They have highlighted the need to understand the current availability and future sustainability of water resources under climate change in a region dominated by rain-fed subsistence agriculture. This project aims to establish the link between rain-producing atmospheric processes and available water resources.

It will provide a comprehensive assessment of how climate change affects rainfall amount and variability, surface water availability, and groundwater recharge in a representative watershed in Ethiopia. This knowledge could provide important insight for the strategic planning of the region’s long-term sustainable development, particularly in terms of increasing food security, reducing vulnerability, and building resilience to climate-related natural disasters.

The project will also foster international research collaboration between the US and Ethiopian scientists and students, and provide training, mentoring, and career development for under-represented groups in geological and hydrological sciences.

This project aims to establish the link between regional climate patterns and water supply in the Horn of Africa (HOA). This knowledge is critical in understanding the sustainability of water resources under climate change in this region. To achieve this, the investigators adopt an interdisciplinary approach that integrates synoptic climate analysis and isotope hydro-geochemistry.

The main objectives of this project include: (1) identify rain-producing circulation patterns and establish their inter-and intra-seasonal variability and past change in response to global warming, (2) establish distinct isotopic signatures of rainfall from different weather types through high-resolution precipitation isotope measurements in multiple sites across the climatic and elevation gradients, and (3) quantify the contribution of rainfall from different weather types to surface flow and groundwater recharge. The outcomes of this study will bridge the gap between changes in the large circulation patterns and their impacts on water resource availability at the watershed scale.

The results can also be used to improve predictions of future rainfall variability and change, and assessment of future availability of surface and groundwater resources. In addition, the new water isotope dataset will provide a baseline for future hydro-climatic research and better interpretation of isotope climate proxy in the geologic record in a region important for human evolution.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.