Data assimilation for regional water balance studies in arid and semi-arid areas - (Case study: the Volta basin upstream the Akosombo dam in Ghana)

Accurate quantification of the water balance components is of vital importance for adequate water resources management in all parts of the world. In arid and semi-arid regions this need is even more pronounced due to the existing conflicts in water use and the anticipated shortage of water for further development of the region. In industrialized countries a dense network of in-situ hydrometeorological observation stations provide the necessary data to evaluate these water balance components. In developing countries situated in arid and semi-arid regions of the world the installation of such dense networks is often hampered by economic reasons and the availability of specialized personnel to operate and maintain these networks. Basic research is therefore needed to overcome the needs for such in-situ observation networks. One obvious alternative is the development of estimation procedures based on remotely sensed information of the Earth's surface and lower atmosphere.