The Sudans Nile within the Sudans has no significant tributaries. The amount of rainfall increases towards the south. In the north there is the very dry Nubian Desert; in the south there are swamps and rainforest. The Sudans’s rainy season lasts for about three months (July to September) in the north, and up to six months (June to November) in the south. The dry regions are plagued by sandstorms, known as haboob, which can completely block out the sun. In the northern and western semi-desert areas, people rely on the scant rainfall for basic agriculture and many are nomadic, travelling with their
Kalahari Desert activities within the reserve. Botswana Namibia South Africa Kalahari Desert The Kalahari Desert is a large semi-arid sandy savanna in Southern Africa extending for , covering much of Botswana, parts of Namibia and regions of South Africa. "Kalahari" is derived from the Tswana word "Kgala", meaning "the great thirst", or "Kgalagadi", meaning "a waterless place"; the Kalahari has vast areas covered by red sand without any permanent surface water. Drainage of the desert is by dry valleys, seasonally inundated pans and the large salt pans of the Makgadikgadi Pan in Botswana and Etosha Pan in Namibia. The only permanent river,