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CHG Background
Figure 1. Annual runoff and scenes from Ethiopia. Enough water exists in many regions to overcome drought. Better scientific management practices of water resources is required.

The problem: too much water - or not enough. In many developing nations coping with hydrologic extremes is equivalent in cost and potential outcome to war (Kates, 2000). Many countries are losing this struggle for water. According to a recent UN World Water Development report (WWD, 2003) the average supply of water per person world-wide is expected to drop by a third in the next 20 years, with between 2 to 7 billion people facing water shortages by 2050. Fifty nations face chronic food shortages, with 20% or more of their populations under-nourished (FAO, 1999). Caught between increasing demand and shrinking opportunities, many of the global poor adapt desperately, with displacements and unsustainable agricultural practices that promote a spiral of land degradation. The impact of drought is not limited to the poorest nations. Economic growth for the Republic of South Africa, for example, with a diverse economy (only about 2% of its GDP is based on agriculture), has a strong (0.7) positive correlation with seasonal rainfall totals (Jury, 2002). Too much water may also bring disaster. Diseases associated with wet conditions such as malaria and Rift Valley Fever exact a tremendous toll on people and their livelihoods, taking thousands of lives and costing billions of dollars (WHO, 2001), and account for 19% of all infectious disease-related deaths (WHO, 2000). Furthermore, flooding can eradicate years of painful economic advances, gained through fiscal discipline and hard work, in a single week. Such was the case for Honduras and Mozambique, when struck, respectively, by Mitch and Eline in 1998 and 2000. Economic growth in Mozambique went from 8% to 2% a year, almost overnight (BBC, 2001).

Figure 2. USGS Stream flow model output for Mozambique, May 8th, 2003 (top-left), photo and radar imagery of flooding in 1999 (top-right) and tropical cyclone Mantua reaching Madagascar on May 8th, 2003.

The solution – science in action. The global water crisis has been caused by "inertia at the leadership level" (WWD, 2003). Limited hydrologic science and resources contribute to this inertia. Effective decision-making grows out of the clash and conflict of many diverging opinions (Drucker, 1967). Where scientific inquiry is stunted, the possibilities for future development wither (Einstein, 1949). From the dawn of history, successful cultures have had the means to anticipate, mitigate and alleviate the impacts of hydrologic extremes (Fagan, 1999). Current science combines ever-growing satellite-based observations with constantly improving models of our climate, rivers and crops to provide better and better information sooner faster and cheaper than ever before. Science tells us that many of the water-related emergencies of the developing world can be effectively mitigated. Average grain yields have doubled since 1950, and per-person caloric intake has increased (WWD, 2003). Improved hydrologic forecasting and management practices can continue this trend. For example, Ethiopia, chronically stricken by drought, has substantial annual surpluses of runoff – which could be stored in ponds and used to offset the effects of drought (Rockstrom, 2000) (Figure 1). Stream flow models operating in near-real time and in forecast mode can identify at-risk basins, allowing the worst effects of flooding to be avoided (Figure 2). Seasonal precipitation forecasts can provide guidance months in advance, allowing nations to adequately prepare themselves for higher than normal rains (as expected for Central America this summer, Figure 3), or for the specter of drought (as was correctly anticipated this past winter in Southern Africa, Figure 4).

These results stem from the work of an international team of Famine Early Warning System Network (FEWS NET) scientists working in the United States and abroad. Research scientists in the United States, with full access to the fruits of technology, are well-situated to rapidly develop new theories and tools. Regional scientists, stationed in developing countries, can translate new theories and tools rapidly into practice, and communicate their results to decision makers. This model of 'science for development' has proven effective for the CHG.

Figure 3. Forecast seasonal precipitation anomalies [mm/season] for the 2003 La Primera (June-August) maize growing season in Central America. Based on an interpretation of the International Research Institute Climate Assessment. Also shown are scenes of devastation caused by Hurricane Mitch.
Figure 4. Comparison of maize Water Requirement Satisfaction Index forecast (made in mid-November, 2002) with current end-of-season values for Southern Africa. Values are expressed as a percent of the historic median for each location.


  • BBC, 2001: "Mozambique's Flooding Causes Economy to Ebb", Friday, 20 April, 2001; BBC World Service Newsroom, http://news.bbc.co.uk/1/hi/world/africa/1288183.stm.
  • Drucker, P., 1967: The Effective Executive. Harper & Row, 178 pp.
  • Einstein, A., 1949: The world as I see it. The Philosophical Library, 112 pp.
  • Fagan, B., 1999: Floods, Famines and Emperors. 1 ed. Basic Books, 284 pp.
  • FAO, 2001: When People live with hunger and fear starvation. 2001. The state of food insecurity in the world. http://www.fao.org/docrep/003/y1500e/y1500e00.htm
  • Jury, M., R., 2002: Economic Impacts of Climate Variability in South Africa and Development of Resource Prediction Models. Journal of Applied Meteorology, 41, 46-55.
  • Kates, R. W., 2000: Cautionary Tales: Adaptation and the Global Poor. Climatic Change, 45, 5-17.
  • Rockstrom, J., 2000: Water Resources Management in Smallholder Farms in Eastern and Southern Africa: An Overview. Phis. Chem. Earth (B), 25, 275-283.