Drought

DICTIONARY DEFINITIONS of drought are very straightforward and brief: drought is a long period without rainfall. There have been many periods of this type, and the impact of a severe drought on people and animals within the affected region has been devastating. There are many examples of the impact of severe drought.

The Dust Bowl in the 1930s forced many thousands of people to abandon their land in the midwest of the United States. Drought in the Sahel region of Africa from 1968 to 1974 took the lives of hundreds of thousands of people and millions of farm animals. In the first few years of the 21st century, the threat of drought is widespread. Large areas in sub-Saharan Africa continue to suffer from lack of rainfall. In southern Africa, estimates suggest that more than 15 million people are at risk of starvation. Ethiopia is another African country in danger of losing millions of people because of drought and ensuing famine. Experts speculate that the loss of life in the current crisis could exceed the 1984 to 1985 drought occurrence when over one million people perished. The Sahel, the semidesert region adjacent to the southern edge of the Sahara, is having food shortages because of low agricultural production during periods of persistent drought. Other regions in the world are also having drought conditions more frequently than in the past. All indications are that this situation will continue in the most susceptible regions.

The explanation for drought is complex. Both natural occurrences and the actions of humans contribute to drought formation. The areas most prone to drought are the semideserts that lie adjacent to the great deserts of the world. Deserts originally formed beneath the naturally occurring high-pressure systems centered at approximately 30 degrees north and south of the equator. These regions are under the influence of dry air descending from the high-pressure systems. The deserts are essentially devoid of vegetation and receive low levels of precipitation. The Atacama Desert in South America is extremely dry: no rainfall has ever been recorded in large parts of this desert.