Lake Chad

Lake Chad (French: Lac Tchad) is a historically large, shallow, endorheic lake in Africa, which has varied in size over the centuries. According to the Global Resource Information Database of the United Nations Environment Programme, it shrank as much as 95% from about 1963 to 1998, but "the 2007 (satellite) image shows significant improvement over previous years." Lake Chad is economically important, providing water to more than 68 million people living in the four countries surrounding it (Chad, Cameroon, Niger, and Nigeria) on the edge of the Sahara Desert. It is the largest lake in the Chad Basin.

Geography and hydrology

Lake Chad is mainly in the far west of Chad, bordering on northeastern Nigeria. The Chari River, fed by its tributary the Logone River, provides over 90% of Lake Chad's water, with a small amount coming from the Yobe River in Nigeria/Niger. Despite high levels of evaporation, the lake is fresh water. Over half of the lake's area is taken up by its many small islands (including Bogomerom archipelago), reedbeds and mud banks, and a belt of swampland across the middle divides the northern and southern halves. The shorelines are largely composed of marshes.

Chad

Coordinates: 15°N 19°E / 15°N 19°E / 15; 19

Chad (ⁱ/tʃæd/; Arabic: تشاد‎ Tshād; French: Tchad), officially the Republic of Chad (Arabic: جمهورية تشاد‎ Jumhūrīyat Tshād; French: République du Tchad), is a landlocked country in Central Africa. It is bordered by Libya to the north, Sudan to the east, the Central African Republic to the south, Cameroon and Nigeria to the southwest and Niger to the west. It is the fifth largest country in Africa in terms of area.

Chad has several regions: a desert zone in the north, an arid Sahelian belt in the centre and a more fertile Sudanian Savanna zone in the south. Lake Chad, after which the country is named, is the largest wetland in Chad and the second-largest in Africa. N'Djamena, the capital, is the largest city. Chad is home to over 200 different ethnic and linguistic groups. Arabic and French are the official languages. Islam and Christianity are the most widely practiced religions.

Beginning in the 7th millennium BC, human populations moved into the Chadian basin in great numbers. By the end of the 1st millennium BC, a series of states and empires rose and fell in Chad's Sahelian strip, each focused on controlling the trans-Saharan trade routes that passed through the region. France conquered the territory by 1920 and incorporated it as part of French Equatorial Africa. In 1960, Chad obtained independence under the leadership of François Tombalbaye. Resentment towards his policies in the Muslim north culminated in the eruption of a long-lasting civil war in 1965. In 1979, the rebels conquered the capital and put an end to the south's hegemony. However, the rebel commanders fought amongst themselves until Hissène Habré defeated his rivals. He was overthrown in 1990 by his general Idriss Déby. Since 2003, the Darfur crisis in Sudan has spilt over the border and destabilised the nation, with hundreds of thousands of Sudanese refugees living in and around camps in eastern Chad.

Lake

A lake is an area of variable size filled with water, localized in a basin, that is surrounded by land, apart from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean (except for sea lochs in Scotland and Ireland), and therefore are distinct from lagoons, and are also larger and deeper than ponds, though there are no official or scientific definitions. Lakes can be contrasted with rivers or streams, which are usually flowing. However most lakes are fed and drained by rivers and streams.

Natural lakes are generally found in mountainous areas, rift zones, and areas with ongoing glaciation. Other lakes are found in endorheic basins or along the courses of mature rivers. In some parts of the world there are many lakes because of chaotic drainage patterns left over from the last Ice Age. All lakes are temporary over geologic time scales, as they will slowly fill in with sediments or spill out of the basin containing them.

Many lakes are artificial and are constructed for industrial or agricultural use, for hydro-electric power generation or domestic water supply, or for aesthetic or recreational purposes.