Kalahari Acacia-Baikiaea woodlands Kalahari Acacia-Baikiaea woodlands Kalahari Acacia-Baikiaea woodlands is an ecoregion located in Botswana, northern Namibia, South Africa and Zimbabwe. These woodlands cover the center of southern Africa, from northern Namibia diagonally through to southeast Botswana and just into the Tuli Block of South Africa. In Botswana there is another area running north from the Okavango Delta and the Makgadikgadi Pan towards the border of the Chobe National Park and then east to the border with Zimbabwe. All this is semi-arid sandveld with little surface water. Droughts occur approximately every seven years. Rainfall, when it occurs, is mostly in the summer, from
Kalahari Desert annual rainfall ranging from around 110 mm (close to aridity) to more than 500 mm in some areas of the north and east. During summer time in all regions rainfall may go with heavy thunderstorms. In the driest and sunniest parts of the Kalahari, over 4,000 hours of sunshine are recorded annually on average. In the Kalahari, there are two main mechanisms of atmospheric circulation, dominated by the Kalahari High anticyclone: There are huge subterranean water reserves beneath parts of the Kalahari; the Dragon's Breath Cave, for example, is the largest documented non-subglacial underground lake on the planet. Such reserves