A drought can be considered as occurring in an area when there has been a deficiency in precipitation over an extended period of time resulting in a water shortage for some activity, group, or environmental sector. Droughts can go on for several years, but even a short, intense drought can cause significant damage and harm the local economy. This global phenomenon has a widespread impact on agriculture. Lengthy periods of drought have long been a key trigger for social upheaval.
A major problem is presented by Drought in the Kunene River Basin, affecting the availability and distribution of water for agriculture and other major water uses.
Climate change may be responsible for increased frequency and intensity of drought in the region.
Source: ©iStockPhoto/FotoVoyager 2006
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The following box displays definitions for various drought types.
Definitions for Various Drought Types
Meteorological drought is a reduction in rainfall compared with the average over a specified period. A drought is said to occur when a large area receives rainfall less than 75 % of normal for an extended period.
Agricultural drought is inadequate supply of the moisture required by a crop during each different growth stage, resulting in impaired growth and reduced yields.
Hydrological drought is the impact of a reduction in rainfall on surface and underground water resources that reduces the supply of water for irrigation, hydro-electrical power generation, and other household and industrial uses.
Socio-economic drought relates to the impact of drought on human activities, including both indirect and direct impacts on agricultural production and the wider economy.
Source: INGC/ FEWS NET Mind 2003
Economic development in developing countries is currently threatened by weather-related disasters such as floods and droughts (World Water Assessment Programme 2009). Water shortages can seriously harm the economy of a country or region, constraining development and reducing economic growth as financial and hydrological resources are expended to counter the drought. Multi-year droughts can have a lasting legacy, resulting in long-term suffering for agriculturally dependent rural communities and reducing national and regional growth rates significantly.
Of the two countries sharing the Kunene River basin, Namibia, with its reliance on the hydroelectric power generated at Ruacana and the abstraction of water from the river at Calueque to supply over 40% of its population with drinking water, is the most susceptible to drought in the basin.
The frequent occurrence of the El Niño Southern Oscillation (ENSO) phenomena complicates the expected rainfall pattern that is normally controlled by the movement of the Inter-Tropical Convergence Zone (ITCZ) (IDRC 2008).
