Africa has been severely affected by droughts in the past, contributing to food insecure conditions in several African countries. In view of the (even more) severe drought conditions and water shortage that may be expected in sub-Saharan Africa in the coming years, efforts should focus on improving drought management by ameliorating resilience and preparedness to drought.
This study contributes to the development of a modelling framework for hydrological drought forecasting in sub-Saharan Africa as a step towards an effective early warning system. The proposed hydrological drought forecasting system makes use of a hydrological model that was found to be suitable for drought forecasting in Africa and could represent the most severe past droughts in the Limpopo Basin. The modelling results showed that there is an added value in computing indicators based on the hydrological model for the identification of droughts and their severity. The proposed seasonal forecasting system for the Limpopo Basin was found to be skilful in predicting hydrological droughts during the summer rainy season. The findings showed that the persistence of the initial hydrological conditions contribute to the predictability up to 2 to 4 months, while for longer lead times the predictability of the system is dominated by the meteorological forcing.
An effective drought forecasting and warning system will hopefully contribute to important aspects in the region such as water security, food security, hazard management, and risk reduction.
Table of Contents
1 General introduction
2 A review of continental scale hydrological models and their suitability for drought forecasting in (sub-Saharan) Africa
3 Comparison of different evaporation estimates over the African continent
4 Identification and simulation of space-time variability of past hydrological drought events in the Limpopo River basin
5 Downscaling the output of a low resolution hydrological model to higher resolutions
6 Hydrological drought forecasting and skill assessment for the Limpopo River basin
Patricia M. Trambauer Arechavaleta (Montevideo, Uruguay, 1982) obtained her BSc, in Civil Engineering, specialization Hydraulic and Environmental Engineering in 2007 from the Faculty of Engineering, State University in Montevideo, Uruguay. While studying she was already working at the consultant company CSI Ingenieros as a project engineer assistant, and after graduation she became a project engineer at the same company.
In 2010 she obtained her MSc in Water Science and Engineering - specialization Hydrology and Water Resources - from UNESCO-IHE, Delft, The Netherlands with distinction. Her thesis was entitled "Surface water and shallow groundwater flow systems in lowland peat areas – Case study at the Zegveld experimental farm".
February 2011, she started working on her PhD research at the Department of Water Science and Engineering at UNESCO-IHE. Her research was part of a larger project "Improved Drought Early Warning and Forecasting to Strengthen Preparedness and Adaptation in Africa" (DEWFORA), a collaborative project funded under the Seventh Framework Programme (FP-7) of the EU under the theme "Early warning and forecasting systems to predict climate related drought vulnerability and risks in Africa" (ENV 2010.1.3.3-1). The project involved the collaboration of 19 European and African partners; further details can be found at www.dewfora.com.