Africa's Water Crisis
Major drops in rainfall caused by global warming threaten rivers and other local sources of fresh water in densely populated areas of Africa, according to a new study published by Science magazine.
Some of these areas, particularly in southern Africa, already suffer periodic droughts, so further declines in rainfall could have major impacts on people who depend on local water supplies, according to the two authors, Maarten de Wit and Jacek Stankiewicz of the Africa Earth Observatory Network (AEON) at the University of Capetown.
Other particularly vulnerable areas include a narrow band of territory that stretches from Senegal eastward to Sudan and crosses several important water bodies that supply populations downriver, such as the Sudd swamps in the Nile Basin and the Niger River. They also include parts of East Africa south of Somalia.
Because much of the rainwater is absorbed by soil and plants before it can reach streams and rivers, declines in rainfall in these areas translate into much steeper declines in the amount of water available for human use. A 10-percent drop in precipitation in regions that receive 20 inches of rainfall per year could result in a 50 percent drop in surface drainage.
Altogether, the decline in rainfall and the resulting decrease in yearly drainage -- rivers, lakes and other bodies of water that hold or carry surface water throughout the year -- will affect access to water across 25 percent of Africa by the end of the century, according to the study. Download the study.
March 4, 2006 8:00 AM | Category: Drought