II.

Land and Resources

The Kalahari is mostly flat, with an average elevation of about 1,000 m (3,000 ft) above sea level. The sands of the Kalahari are red, brown, or white in places. Parallel lines of dunes—typically lying along a north-to-south or northwest-to-southeast orientation, depending on the prevailing winds—cover substantial areas of the Kalahari, and are concentrated in the west. The dunes vary in height from about 6 m (20 ft) to 60 m (200 ft), are separated by channels of varying width, and can be up to 80 km (50 mi) long.

The Kalahari has a semiarid climate, and droughts are frequent. The region receives about 200 mm (8 in) of precipitation a year, mainly between the months of October and May. The rainfall pattern is highly variable, however, and precipitation can fluctuate by more than 100 percent between years. Daytime temperatures range between 35° to 45°C (95° to 113°F) from October to March, the hottest months, and can drop below freezing between June and August.

The only permanent surface water in or around the Kalahari is the Boteti River. The Boteti flows out of the Okavango Delta, an extensive swampy region at the northern edge of the Kalahari Desert in northern Botswana. Heavy rains in central Angola cause periodic flooding of the delta, and the Boteti carries the overflow east into Lake Xau and the Makgadikgadi Pan on the northeastern fringe of the desert. Other channels carry water south into Lake Ngami. Elsewhere in the desert, short-lived networks of streams and rivers flow after rains. Subterranean water can be found below the temporary watercourses. These streams flow into depressions in the desert, known as pans. Pans vary in size from a few meters to tens of kilometers in diameter, and provide temporary or semipermanent sources of surface water.

The Kalahari contains a mix of acacia woodland, acacia scrub, savanna grasslands, and palm trees. Wildlife in the Kalahari has adapted to survival without a permanent water supply. Antelope such as eland, gemsbok, springbok, hartebeest, steenbok, kudu, and duiker are common, as are giraffe, warthog, hyena, jackal, the bat-eared fox, the rare wild dog, and a host of smaller animals and many species of birds. Plant species are most diverse around pans and these areas are a rich food resource for animals. The largest protected areas in the Kalahari are the Central Kalahari Game Reserve in Botswana and the Kgalagadi Transfrontier Park, shared by Botswana and South Africa.