Multi-Model Hydrologic Forecasts

Multi-model Hydrologic Forecasts in Pilot Basins in Africa (NASA SERVIR & ICIWaRM-UNESCO)

Through a continuing collaboration between The University of Arizona and diverse African partner institutions, the NASA SERVIR-Africa Program and ICIWaRM have been developing monitoring tools and real-time streamflow forecasting applications using satellite precipitation measurements and numerical weather model results. This initiative started with work in the Senegal River Basin, where a detailed and applied research agenda was developed with the International Senegal Basin Authority (Organisation pour la Mise en Valeur du Fleuve Senegal, OMVS Dakar) to help improve management tools to face complex challenges in the basin.

With a 4 year NASA SERVIR funded project, SERVIR Water Africa Arizona Team (SWAAT) at The University of Arizona has developed real-time monitoring and forecasting applications focusing on three pilot basins in Africa (The Mara River in Kenya & Tanzania, The Upper Zambezi in Zambia, Namibia & Angola and the Tekeze River in Ethiopia & Eritrea). Specifically, the project aims at monitoring water resources availability, and to provide 7 to 12 day streamflow forecasts with a multi-model approach using real-time satellite measurements and near-term weather forecasts as inputs for hydrologic modeling. The project is benefiting from a strong linkage with the end-user communities, through our partnership with the Southern Africa Development Community Climate Services Center (SADC – CSC), formerly the Drought Monitoring Center (15 member states in East-Central and Southern Africa), the Regional Center for Mapping of Resources for Development (RCMRD, Kenya) and other governmental and non-governmental entities.

In response to specific needs reported from the field, such as the lack of quantitative tools to estimate water availability at resolutions useful to decision-making, we have been developing tailored applications that provide near-real time estimates of water availability. These applications use (i) satellite-based precipitation and evapotranspiration products from NASA satellites, and (ii) near-term precipitation forecasts from NOAA (National Oceanic and Atmospheric Administration) to drive hydrologic models. By enabling continuous and near-real time monitoring and assessment of water resources, these applications can support a broad range of water resources management activities that are directly linked to economic, environmental and livelihood security. Our multi-model approach can facilitate local actors in the appropriation and use of the most adequate tools to address site-specific challenges.  

Near real-time displays of precipitation for the Mara, Upper Zambezi and Tekeze river basins, as captured by several satellite precipitation products and after bias correction with a reference dataset, are available on the SWAAT rainfall page. Ten-day experimental forecast of streamflows in the river basins, using three hydrologic models and two satellite precipitation products, are also available from the SWAAT forecast page. Two lumped models and the Variable Infiltration Capacity (VIC) Model are used. Developed applications and products are a collaborative output from interactions with NASA’s SERVIR Program Officers and with regional end-users such as those in the SADC-CSC and SERVIR Africa Regions. Special effort is being made to ensure that final products – such as near-real time streamflow forecasts – are easily available to the end-user communities and the public.  

The project also includes a climate change impacts assessment using downscaled projections for East and Southern Africa and the previously developed hydrologic models. Hence, this initiative provides a solid framework in support of both short- and long-term challenges in water resources management and adaptation.