LAKE CHAD

Lake Chad is located mainly in the far west of Chad, bordering on northeastern Nigeria. The Chari River, fed by its tributary the Logone, 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 while the shorelines are largely composed of marshes.

Because Lake Chad is very shallow—only 10.5 metres 34 ft at its deepest—its area is particularly sensitive to small changes in average depth, and consequently it also shows seasonal fluctuations in size of about 1 m every year. Lake Chad has no apparent outlet, but its waters percolate into the Soroand Bodélé depressions. The climate is dry most of the year, with occasional rains from June to December.

Lake Chad French: lac Tchad  is a historically large, shallow, endorheic lake in Africa, the size of which has varied over the centuries. According to theGlobal 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 30 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.

Lake Chad gave its name to the country of Chad. The name Chad is a local word specify meaning "large expanse of water", in other words, a "lake".

Lake Chad is the remnant of a former inland sea, paleolake Mega-Chad. At its largest, sometime before 5000 BC, Lake Mega-Chad was the largest of four Saharan paleolakes, and is estimated to have covered an area of 400,000 km2 150,000 sq mi, larger than the Caspian Sea is today, and may have extended as far northeast as within 100 km 62 mi of Faya-Largea.

Lake Chad was first surveyed from shore by Europeans in 1823, and it was considered to be one of the largest lakes in the world then In 1851, a party including the German explorer Heinrich Barth carried a boat overland from Tripoli across the Sahara Desert by camel and made the first European waterborne survey. British expedition leader James Richardson died just days before reaching the lake

Lake Chad has shrunk considerably since the 1960s, when its shoreline had an elevation of about 286 metres 938 ft above sea level and it had an area of more than 26,000 square kilometres 10,000 sq mi, making its surface the fourth largest in Africa. An increased demand on the lake's water from the local population has likely accelerated its shrinkage over the past 40 years

The size of Lake Chad greatly varies seasonally with the flooding of the wetlands areas. In 1983, Lake Chad was reported to have covered 10,000 to 25,000 km2 3,900 to 9,700 sq mihad a maximum depth of 11 metres 36 ft and a volume of 72 km3 17 cu m

Volcanism

The region shows much evidence of volcanic activity in the last 5000 years. The Katwe-Kikorongo and Bunyaruguru Volcanic Fields, with extensive cones and craters, lie either side of the Kazinga Channel on the north-west shore of the lake. It is thought that Lakes George and Edward have been joined as one larger lake in the past, but lava from these fields flowed in and divided it, leaving only the Kazinga Channel as the remnant of the past union. To the south, the May-ya-Moto thermally active volcano lies 30 km away, and the Nyamuragira volcano in the western Virunga Mountains lies 80 km south, but its lava flo

ws have reached the lake in the past.

The Katwe-Kikorongo field features dozens of large craters and cones covering an area of 30 km by 15 km between lakes Edward and George, and includes seven crater lakes. The largest of these, the 2.5-kilometre-long Lake Katwe, occupies a crater 4 km across and is separated from Lake Edward by just 300 m of land. The crater is about 100 m deep, and Lake Katwe's surface is about 40 m lower than Lake Edward's. It is remarkable that the volcanic origin of this area south-east of the Ruwenzoris was not known until reported by G. F. Scott Elliot in 1894. Stanley visited Lake Katwe in 1889 and noted the deep depression, the salinity of the lake, and a spring of sulphurous water nearby, but failed to connect this to volcanism.

The similarly-sized Bunyaruguru field on the other side of the Kazinga Channel contains about 30 crater lakes, some larger than Katwe.

Settlements

Lake Edward lies completely within the Virunga National Park Congo and the Queen Elizabeth National Park (Uganda) and does not have extensive human habitation on its shores, except atIshango (DRC) in the north, home to a park ranger training facility. About two-thirds of its waters are in the DR Congo and one third in Uganda. Apart from Ishango  the main Congolese settlement in the south is Vitshumbi while the Ugandan settlements are Mweya and Katwe in the north-east, near the crater lake of that name which is the chief producer of salt for Uganda. The Mweya Safari Lodge is the main tourist facility serving both Lake Edward and Lake Katwe. The nearest cities are Kasese in Uganda to the north-east and Butembo in DR Congo, to the north-west, which are respectively about 50 km and 150 km distant by road.