The Namib is a
coastal desert in southern Africa. The name Namib is of Nama origin and means
"vast place". According to the broadest definition, the Namib
stretches for more than 2,000 kilometres 1,200 mialong the Atlantic coasts of Angola,
Namibia, and South Africa, extending southward from the Carunjamba River in
Angola, through Namibia and to the Olifants River in Western Cape, South
Africa. The Namib's northernmost portion, which extends 450 kilometres280 mi
from the Angola-Namibia border, is known as Moçâmedes Desert, while its
southern portion approaches the neighboring Kalahari Desert. From the Atlantic
coast eastward, the Namib gradually ascends in elevation, reaching up to 200
kilometres 120 mi inland to the foot of the Great Escarpment. Annual
precipitation ranges from 2 millimetres 0.079 in in the most arid regions to
200 millimetres 7.9 in at the escarpment, making the Namib the only true desert
in southern Africa. Having endured arid or semi-arid conditions for roughly
55–80 million years, the Namib may be the oldest desert in the world.
The desert geology consists of sand seas near the coast,
while gravel plains and scattered mountain outcrops occur further inland. The
sand dunes, some of which are 300 metres 980 ft high and span 32 kilometres (20
mi) long, are the second largest in the world after the Badain Jaran Desert
dunes in China. Temperatures along the coast are stable and generally range
between 9–20 °C 48–68 °F annually, while temperatures further inland are variable—summer
daytime temperatures can exceed 45 °C 113 °F while nights can be freezing. Fogs
that originate offshore from the collision of the cold Benguela Current and
warm air from the Hadley Cell create a fog belt that frequently envelops parts
of the desert. Coastal regions can experience more than 180 days of thick fog a
year. While this has proved a major hazard to ships—more than a thousand wrecks
litter the Skeleton Coast—it is a vital source of moisture for desert life.
The Namib is almost
completely uninhabited by humans except for several small settlements and
indigenous pastoral groups, including the Ovahimba and Obatjimba Herero in the
north, and the Topnaar Nama in the central region. Owing to its antiquity, the
Namib may be home to more endemic species than any other desert in the world.
Most of the desert wildlife is arthropods and other small animals that live on
little water, although larger animals inhabit the northern regions. Near the
coast, the cold ocean water is rich in fishery resources and supports
populations of brown fur seals and shorebirds, which serve as prey for the
Skeleton Coast's lions. Further inland, the Namib-Naukluft National Park, the
largest game park in Africa, supports populations of African Bush Elephants,
Mountain Zebras, and other large mammals. Although the outer Namib is largely
barren of vegetation, lichens and succulents are found in coastal areas, while
grasses, shrubs, and ephemeral plants thrive near the escarpment. A few types
of trees are also able to survive the extremely arid climate.
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