McCartney M.,Southeast Asia Office of the International Water Management Institute IWMI |
Rebelo L.-M.,Southeast Asia Office of the International Water Management Institute IWMI |
Xenarios S.,Norwegian Institute for Agricultural And Environmental Research Bioforsk |
IWMI Research Report | Year: 2013
By mitigating the vagaries of climatic variability, agricultural water storage is widely anticipated to make a key contribution to climate change (CC) adaptation, particularly in Africa. However, if the planning of water storage is not improved, it is likely that many investments will fail to deliver intended benefits. This report describes different agricultural water storage options and some of the possible implications of CC. It also describes the development of a simple diagnostic tool, based on a set of biophysical and demographic indicators, which can be used to provide a rapid (first-cut) evaluation of the need and effectiveness of different water storage options, under existing and possible future climate conditions. The tool was applied to sub-Saharan Africa and, in more detail, to the Volta Basin and the Ethiopian portion of the Blue Nile Basin. Throughout sub-Saharan Africa, the greatest need for storage was found to be in the Sahelian zone, the Horn of Africa and southern Africa, with more localized hot spots in southern Angola, Rwanda, Burundi and Uganda, as well as Malawi and Mozambique. In Ethiopia and Ghana, the greatest need was found not to be in areas with the least rainfall (as might have been anticipated), but rather in the areas with the highest population density. Based on changes anticipated by the realization of one downscaled 'middle impact' climate change scenario, the effectiveness of storage will decrease in both the Volta and Blue Nile basins in the future. The approach needs to be refined through further research and testing in real planning situations, but nevertheless provides the basis for a more rigorous approach to the planning of future agricultural water storage. © 2013, by IWMI. All rights reserved.