Namib

Namib

Introduction
 a cool coastal desert extending for 1,200 miles (1,900 kilometres) along the Atlantic coast from Namibe (formerly Moçâmedes) in Angola southward across Namibia to the Olifants River in the Cape Province of South Africa. It reaches inland 80 to 100 miles to the foot of the Great Escarpment. The southern portion merges with the Kalahari on the plateau atop the escarpment. Its name is derived from the Nama language, implying “an area where there is nothing.”

      The Namib is arid and is almost totally uninhabited, except for several towns. It is important because of the trade routes that cross it, its mineral deposits, the fisheries of the bordering sea, and its increasing utilization for recreational purposes.

Physical features
      The Namib is divided into three successive north–south-trending strips: the very narrow coastal region along the Atlantic, strongly subject to marine influences; the Outer Namib, occupying the rest of the western half of the desert; and the Inner Namib, constituting the eastern portion. The boundaries between them consist of broad transition zones.

Physiography
      The desert basically consists of a relatively smooth platform of truncated bedrock of various types and ages. Mica-schist and other metamorphics and granite and similar intrusives predominate. The platform rises gradually from the coast to about 3,000 feet (900 metres) at the foot of the escarpment. Scattered isolated mountains rise steeply and abruptly above the platform, and in the northern half several streams have carved deep, steep-walled gorges into it.

      In much of the southern half of the desert the platform is surmounted by a vast expanse of sand—yellow-gray near the coast and brick-red inland—which is derived from the Orange River and from other rivers that flow westward from the escarpment but never reach the sea. The dunes run in lines from north-northwest to south-southeast, with individual dunes having lengths of 10 to 20 miles and reaching heights of 200 to 800 feet. The troughs between these lines of dunes are interrupted by smaller transverse dunes. The extreme southern coastal area consists of wind-scoured bedrock and a few rapidly moving crescent-shaped barchans (barchan) (i.e., dunes convex to the wind). The northern third—the Kaokoveld (Kaokoland) region—consists of gravel plains and rock platforms occurring between scattered, rugged mountains, interspersed with a few large dune fields.

Drainage
 Being an almost rainless area, the Namib has a poorly developed and fragmentary drainage pattern. Water from the interior plateau flows through or into the desert. In the northern half the larger streams reach the sea, but between the Kuiseb and the Orange rivers, every stream terminates in a vlei (salt pan or mud flat) against or among the dunes (see photograph—>).

      A portion of the water of major streams seeps through the sands of the streambeds. The underflow of the Kuiseb River has been tapped 25 miles inland to provide water supplies for Walvis Bay and Swakopmund. A pipeline 80 miles long supplies Lüderitz with water from the seepage of the Koichab, a stream that terminates in the dunes. Only the Cunene and the Orange rivers flow permanently on the surface. Other streams have surface flow only after heavy rainfall in the interior plateaus—they normally flow for no more than a few days in several years.

Soils
      Large areas of the Namib are completely soilless, with bedrock at the surface. Other areas are covered with shifting sand. Soils that do occur are often highly saline, impregnated with gypsum, or cemented firmly by calcium carbonate, the latter forming a calcrete layer just below the surface. Arable soils in the Namib are limited to floodplains and the terraces of major rivers and are subject to occasional inundation.

Climate
      The coastal area is almost totally rainless, yet its air is almost always at or near the saturation point. The cold Benguela Current flows northward along the coast, chilling the air above it and thus producing fog. This cool air moves inland as a southwest sea breeze, creating a temperature inversion about 1,000 feet thick, with fog below and hot, dry air above.

      At the coast, there is little difference in temperature between day and night or between winter and summer. Temperatures are usually between 50° and 60° F (10° and 16° C). Along the inland margins, summer temperatures normally reach about 88° F (31° C); only in areas sheltered from the cooling sea breeze (lee sides of mountains and bottoms of canyons) do temperatures frequently approach those expected in low-latitude deserts—i.e., in excess of 100° F (38° C). Freezing temperatures occur occasionally along the inner edge of the desert. On a few days each year, usually in fall or spring, berg (or mountain) winds, blowing from the east, bring high temperatures (above 100° F), together with dry air and clouds of dust, across the desert to the coast itself. The rare rains occur usually as short-lived torrential thunderstorms.

      Average annual precipitation at the coast is generally about 0.5 inch (13 millimetres), increasing inland, until it reaches 2 inches at the foot of the escarpment. In some years, however, no rain falls at all. Dew, on the other hand, is heavy and for some types of vegetation is more important than the rainfall. In the extreme south, some winter precipitation occurs from frontal storms passing farther south over the Cape region; on rare occasions, snow may fall on the higher southern mountains.

Plant life
      Six vegetational regions may be identified in the Namib: (1) the coastal region, with highly succulent vegetation, which uses moisture derived from the fog, (2) the almost completely barren Outer Namib, (3) the steppes of the Inner Namib, which in many years are barren but which in wet years are covered with short grasses, both annual and perennial, (4) the dunes of the Inner Namib, which produce a surprisingly rich flora of bushes and tall grasses, (5) the larger river channels, along which large trees, particularly acacias, grow, and (6) the southern winter rainfall area, where a succulent bush growth occurs. A curious Namib plant is the tumboa, or welwitschia (Welwitschia mirabilis (tumboa)), whose two gigantic leaves sprawl over the surface of the ground from the crest of its huge root crown.

Animal life
      The plains and dunes of the Inner Namib support large numbers of several varieties of antelope, especially gemsbok (oryx) and springbok, as well as ostriches and some zebras. Elephants, rhinoceroses, lions, hyenas, and jackals are found in the northern Namib, especially along the rivers that flow from the interior highlands to the Atlantic. The dunes of the Outer Namib provide habitats for various types of insects and reptiles, especially beetles, geckos, and snakes, but virtually no mammals. The shore area is densely populated by marine birds (notably flamingos, pelicans, and, in the southern part, penguins), as well as a few jackals, some rodents, and a few colonies of seals. Large quantities of guano are scraped annually from the rocks of several offshore islands.

The people and the economy
      A few San roamed the Namib until early in the 20th century, gathering whatever was edible along the shore, hunting in the Inner Namib, and often depending for water upon the bitter juices of the tsama (tsamma) melon. A small number of Herero continue to herd cattle and goats from waterhole to waterhole in the desert part of the Kaokoveld, living in their traditional manner. A few Topnaar Nama Khoekhoe also graze their sheep and goats on the riverine vegetation along the Kuiseb River. A great part of the Namib is now totally unused and unoccupied, the aboriginal people having left to adopt new homes and new ways of life. A few areas, however, are productive in some way.

      The innermost steppes in the southern half of the desert are divided into private “farms” (ranches), which are operated by Europeans using native labour and are devoted to the raising of Karakul sheep; the wavy-haired pelts of newborn lambs of these sheep are used for fur coats in Europe.

      Much of the central and northern Namib has been set aside for recreation and conservation. The Namib Desert Park in the central area is a desert range for flocks of antelope, zebra, and ostrich. A strip about 130 miles (210 km) in length along the coast northwest of Swakopmund constitutes the National West Coast Tourist Area; within it is the Cape Cross Seal Reserve, which protects a breeding area. Farther north is the Skeleton Coast National Park, where entry is restricted in order to preserve the fragile desert environment.

      A vast area stretching from the Kuiseb River to the Orange River on the South African border and reaching inland some 80 miles (130 km) constitutes the Sperrgebiet (“Prohibited Area”), to which all entry is strictly restricted because of the possible presence of diamonds there. Diamonds are extracted from alluvial beds near the coast by large-scale equipment, chiefly in the area near the mouth of the Orange River.

      There are four cities on the Namib coast. Swakopmund, the summer capital for Namibia and a popular coastal resort town, still retains much of the atmosphere from the days when South West Africa was a German colony. From mid-December to mid-February many functions of the government are transferred from Windhoek to Swakopmund to escape the heat of the interior. Swakopmund has been greatly changed by the development of a large uranium mine located some 25 miles (40 km) inland. Walvis Bay, just to the south of Swakopmund, is a coastal enclave formerly belonging to South Africa that was transferred to Namibia in 1994. It is a modern port city with a mixed population—the Africans consisting partly of Nama families from south-central Namibia but largely of male Ambo from Angola and the northern part of Namibia who have found employment at the port. The port serves as a base for fishing fleets that supply both shore canneries and cannery ships on the open sea. It is also the major transhipment port for Namibia. Lüderitz, a small town on a shallow, rock-strewn harbour, has a small trade with Walvis Bay and Cape Town and is the base of a crayfish (lobster) industry. Oranjemund, a company town of the Namdeb Diamond Corp., is a base for large-scale diamond mining in the alluvial gravels along the southern coast.

      The Namib is crossed by rail lines and tarred roads, both from Walvis Bay-Swakopmund and from Lüderitz, which are integrated with the internal rail and road systems of Namibia and South Africa. Except for roads from Swakopmund north for about 130 miles (210 km), between Swakopmund and Walvis Bay, and from Lüderitz to Oranjemund, no improved roads exist along the coast, in the Kaokoveld to the northwest, or in the area between Walvis Bay and Lüderitz.

Study and exploration
      Cursory exploratory voyages were made along the coast from the 15th to 17th century, Walvis (“Whale Fish”) Bay was used as a base for New England whaling ships in the early 19th century, and there were direct routes for traders and missionaries from Lüderitz and Walvis Bay into the interior. Otherwise, little was known of the Namib until the latter part of the 19th century. After South West Africa was established as a territory of Germany in the early 1890s, the German military began the detailed exploration and mapping of the desert.

Richard F. Logan

Additional Reading
Early descriptions of the Namib include Charles John Andersson, Lake Ngami (1856), an account of a four-year exploration; and Heinrich Vedder, South West Africa in Early Times (1938, reissued 1966; originally published in German, 1934), a detailed history of the region to 1890. Richard F. Logan, The Central Namib Desert, South West Africa (1960), thoroughly studies the area's physical and biological geography. B.J. Huntley (ed.), The Kuiseb Environment: The Development of a Monitoring Baseline (1985), contains a set of excellent articles covering all phases of the environment of a transdesert river valley.Richard F. Logan

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Universalium. 2010.

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