Hands-On Workshop on Remote Sensing for Monitoring Water Fluxes in African Savannas

  • 2017/10/12     South Africa

    Image: Ana Andreu

    Drought periods and erratic rainfall patterns across large parts of Africa result in water-limited environments like savannas, highly sensitive to land management practices and changes in climate. The Workshop on Remote Sensing of Water Use and Water Stress in African Savanna Ecosystem from Local to Regional Scale (20–22 September) organised by Dr Ana Andreu (UNU-FLORES) and Dr Timothy Dube (University of Limpopo) dealt with some of the issues on water management in these areas.

    Monitoring water use and the natural vegetation stress over the semi-arid complex ecosystems can support their long-term productivity. Quantifying water fluxes, however, requires efficient and sound monitoring.

    Remote sensing provides a unique perspective to approach this, with sensors, analytical tools, and models continuously evolving and providing new possibilities to address a more complete space-time description of the land-atmosphere processes.

    The workshop held at University of Limpopo, South Africa aimed to present and discuss the state-of-the-art of remote sensing for African savannas’ water use and stress. Through a hands-on training approach, participants discussed the use of Earth Observation (EO) technology for the estimation of water and energy fluxes, with a special focus on modelling semi-arid complex natural systems evapotranspiration.

    The workshop was part of the TIGER project 410, within the TIGER initiative framework funded by the European Space Agency (ESA). Participants came from the University of Limpopo, the South African Department of Water and Sanitation, the Zambian Water Resources Management Authority, the University of KwaZulu Natal, and the University of the Free State from South Africa, the Council for Scientific and Industrial Research (CSIR), and the South African Space Agency (SANSA).

    Image: Abel Ramoelo

    The three-day workshop was opened by Dr. Ramudzuli, Head of the Geography Department, University of Limpopo, whose inspiring speech was followed by lectures delivered by participating experts. During the workshop, participants engaged heavily with UNU-FLORES’s TIGER Savanna Tool Handbook.


    TIGER Initiative and Project 410

    In December 2015 UNU-FLORES, together with the University of Limpopo and the University of Western Cape (South Africa), were selected as one of the ten TIGER Water for Agriculture teams for conducting joint research for integrated water management, within project 410 “Remote Sensing of Water Use and Water Stress in African Savanna Ecosystem from Local to Regional Scale: Implications for Land Productivity”. The TIGER initiative, launched by the European Space Agency (ESA) in 2002, promotes the use of Earth Observation (EO) data to improve Integrated Water Resources Management in Africa, while strengthening the scientific collaboration between African and European partners. The handbook is co-authored by the European lead of the project, Dr Ana Andreu Mendez, and the African lead, Dr Timothy Dube.

    Day 2 started with the presentation of Dr Zoltan Vekerdy (University of Twente) on the TIGER Initiative, other TIGER projects, and EO tools, followed by a training given by Dr Andreu, where participants could try their own hands on available open and free EO data and tools.

    Image: Timothy Dube

    Wrapping up the final day, participants took stock of the tools available, which tools they needed, and discussed where the bottlenecks are. Participants remarked the importance of having enough information/resources to influence policies, and to set up robust ones that countries in Africa can follow. The importance of having reliable EO sources with optimal resolutions and affordable, but also in situ data was also highlighted. Having methodologies to determine water volume and location of reservoirs in order to know which resources we have for managing purposes also proved useful.

    The difficulty in coordination between stakeholders, researchers, and agencies was noted, as well as the importance of transferring knowledge in all fields and across all scales and generations. The challenge that remains: to share, integrate, and make information freely available, and to expose stakeholders to this information in order to engage them.