Drought forecasting in Africa

Written by Emma Meurs, on 14 October 2014

Drought is considered a natural hazard with a very large impact on people and the environment and is one of the largest water related disasters in Africa. For the DEWFORA project which was completed last year, UNESCO-IHE as part of a large consortium developed a framework for monitoring, predicting, timely warning and responding to droughts applicable within the institutional context of African countries. Micha Werner, Associate Professor of Hydraulic Engineering, Shreedhar Maskey, Associate Professor of Hydrology and Water Resources and Patricia Trambauer, PhD fellow at UNESCO-IHE elaborate on the ins and outs of drought forecasting in Africa.

There is a global need for information on droughts and how to manage them. Drought events have resulted in extensive damage to livelihoods, environment and the economy. Recent predictions on climate change suggest this situation may worsen, projecting an increased frequency and severity of drought in many areas. DEWFORA focused in particular on drought forecasting as an approach to manage drought; it stands for improved Drought Early Warning and FORecasting to strengthen preparedness and adaptation in Africa.

Micha Werner, who was the coordinator of the project through his affiliation at Deltares, underlines the relevance of the research: "Flood forecasting has advanced throughout the years much more than drought forecasting. Now we see that drought forecasting is getting more and more attention, also outside the scientific world. During a high level policy meeting hosted by the World Meteorological Organization (WMO) in March 2013 several strategies were adopted on drought management, and these clearly identified forecasting and warning as key".

Nineteen partners collaborated in the project, a large consortium with complementary expertise in forecasting and drought management. "For the success of a big consortium like this, it is important to have a clear and of course complementary role for each partner. It also helps if you work with a partner you have worked with before. One of the strengths of UNESCO-IHE is its broad network. Partners like WaterNet and NBCBN-RE were established in partnership with UNESCO-IHE, so they are obvious partners to work with in projects like these", says Shreedhar Maskey.

Ready to use framework for policy making

The objective was to study and establish a framework on how to develop drought forecasting in order to contribute to policy with that framework. Secondly, the aim was to do science. The team developed a protocol for drought forecasting and warning (see illustration) that demonstrates a strong emphasis on science, but also on outreach and capacity development. A clear example is the online course that is now offered by organisations such as the UN convention for combating desertification, but can in fact be followed by anyone interested in the subject.

Using hydrological models for drought problems

Shreedhar Maskey: "UNESCO-IHE contributed to the project from the hydrological modelling point of view. In drought forecasting, we start with meteorological forecasting; the next phase is hydrological forecasting. One of the things we emphasised is that hydrological models are usually not used for drought problems, but that these models have a lot of potential to provide useful information on drought conditions. From a hydrological model we get outputs such as evaporation, soil moisture, river runoff and even changes in reservoir storage, which are directly relevant for drought management. Our goal was to show the added value of the model. Secondly, we wanted to strengthen UNESCO-IHE's position on drought. We have been doing a lot work on floods so far, but hardly any in droughts". UNESCO-IHE is developing a short course on drought forecasting for next year and is also looking into the potential of offering a refresher course for its alumni.

"Our research scope in DEWFORA was the whole of Africa but we did focus on some case studies, including the Eastern Nile basin, the Limpopo basin and the Inner Niger Delta, as well as the Oum-er-Rbia basin in Morocco. The conclusions found for these basins, such as those for the Limpopo basin, can very well be transferred to other basins like the adjacent Incomati basin, but also on a global level. I was curious to study if a hydrological model can add something to identifying and forecasting droughts. For example, it might not be a dry year according to the meteorological situation but antecedent conditions in the soil can also be a factor for a year to be considered dry or wet. I would like to test our hydrological forecast for this coming season to see what actually happens. We were expecting a drought due to the strong El Nino signal a few months ago, but now the signal is milder and it seems that El Nino will not be as strong as it was forecasted some months ago" explains Patricia Trambauer.

Future plans

The DEWFORA team is currently looking at new calls related to Horizon2020. The focus will be a bit broader and will also include themes such as water security, supply and sanitation. The team believes it will have a good chance of succeeding as the project officer of the EU recently earmarked DEWFORA a very successful project. The EU is planning to interview Micha Werner about DEWFORA and to communicate its impact. In addition, as a result of the work in the project UNESCO-IHE and other partners are now involved in the Global Drought Information System (GDIS), and are exploring possibilities to stay involved in that development.

Micha Werner: "It was not our scope to make an operational forecasting system in this project, but that question is still out there. This needs to be discussed among organisations that have a mandate for providing operational drought forecasts. We do not have that mandate, but we do contribute to efforts that can really make that happen".