The Sahel Region
CE397 – Transboundary Water Resources
February 7th, 2008
The Sahel region is an eco-climate zone located on the southern edge of the Sahara desert. The region spans across Nigeria, Sudan, Senegal, Mauritania, Mali, Burkina Faso, Niger, and Chad (Ethiopia and Somalia are sometimes included in the Sahel region). The name, Sahel, comes from the Arabic work for “border” or “margin”. The region gained this name because it serves as the southern border to the Sahara. It is the transitional zone between the dessert and the more tropical south central Africa. Figure one gives shows the geographic location of the region.
Figure 1: The Sahel region of Africa
The countries of the region are similar in climate, land cover and economy. The Sahel is covered with brush, grasses, and stunted trees. The dominant industries are based in agriculture and herding livestock, much of which depends on rainfall. The Sahel region experiences strong year-to-year variations in climate. The rainfall varies from 200mm to 600mm a year. Over the past century the annual precipitation has decreased. Most of the rain occurs during three to four months of summer.
The rain has decreased, but the number of people depending on it has increased. In the past 35 years the Sahel has experienced rapid growth in population. In 1961 the Sahel was home to approximately nineteen million people. By 2000 this had exploded to 50 million. The population boom has resulted in an expansion of agricultural lands and grazing lands for livestock.
As mentioned above, the Sahel is subject to infrequent precipitation, ranging from 200mm to 600mm a year. Most of this rain falls in the summer during the movement of the intertropical convergence zone. This meteorological event results in a monsoon type pattern. Some years this can result in a fair amount of rain; however, it maybe isolated to one area or is so intense in...