Geography of Somalia
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Geography of Somalia - Africa's easternmost country, Somalia has a land area of 637,540 square kilometers. Somalia occupies the tip of a region commonly referred to as the Horn of Africa--because of its resemblance on the map to a rhinoceros's horn--that also includes Ethiopia, Eritrea and Djibouti.
Somalia's terrain consists mainly of plateaus, plains, and highlands. In the far north, however, the rugged east-west ranges of the Karkaar Mountains lie at varying distances from the Gulf of Aden coast. The weather is hot throughout the year, except at the higher elevations in the north. Rainfall is sparse, and most of Somalia has a semiarid-to- arid environment suitable only for the nomadic pastoralism practiced by well over half the population. Only in limited areas of moderate rainfall in the northwest, and particularly in the southwest, where the country's two perennial rivers are found, is agriculture practiced to any extent.
The local geology suggests the presence of valuable mineral deposits. Somalia's long coastline (3,025 kilometers) has been of importance chiefly in permitting trade with the Middle East and the rest of East Africa.
[edit] Climate
Climate is the primary factor in much of Somali life. For the large nomadic population, the timing and amount of rainfall are crucial determinants of the adequacy of grazing and the prospects of relative prosperity. There are some indications that the climate has become drier in the last century and that the increase in the number of people and animals has put a growing burden on water and vegetation.
Somalis recognize four seasons, two rainy (gu and day) and two dry (jiilaal and hagaa). The gu rains begin in April and last until June, producing a fresh supply of pasture and for a brief period turning the desert into a flowering garden. Lush vegetation covers most of the land, especially the central grazing plateau where grass grows tall. Milk and meat abound, water is plentiful, and animals do not require much care. The clans, reprieved from four months' drought, assemble to engage alternately in banter and poetic exchange or in a new cycle of hereditary feuds. They also offer sacrifices to Allah and to the founding clan ancestors, whose blessings they seek. Numerous social functions occur: marriages are contracted, outstanding disputes are settled or exacerbated, and a person's age is calculated in terms of the number of gus he or she has lived. The gu season is followed by the hagaa drought (July-September) and the hagaa by the day rains (October-November). Next is jiilaal (December-March), the harshest season for pastoralists and their herds.
Most of the country receives less than 500 millimeters of rain annually, and a large area encompassing the northeast and much of northern Somalia receives as little as 50 to 150 millimeters. Certain higher areas in the north, however, record more than 500 millimeters a year, as do some coastal sites. The southwest receives 330 to 500 millimeters. Generally, rainfall takes the form of showers or localized torrential rains and is extremely variable.
Mean daily maximum temperatures throughout the country range from 30 °C to 40 °C, except at higher elevations and along the Indian Ocean coast. Mean daily minimum temperatures vary from 20 °C to more than 30 °C. Northern Somalia experiences the greatest temperature extremes, with readings ranging from below freezing in the highlands in December to more than 45 °C in July in the coastal plain skirting the Gulf of Aden. The north's relative humidity ranges from about 40 percent in midafternoon to 85 percent at night, varying somewhat with the season. During the colder months, December to February, visibility at higher elevations is often restricted by fog.
Temperatures in the south are less extreme, ranging from about 20 °C to 40 °C. The hottest months are February through April. Coastal readings are usually five to ten degrees cooler than those inland. The coastal zone's relative humidity usually remains about 70 percent even during the dry seasons.
[edit] Terrain, Vegetation, and Drainage
Physiographically, Somalia is a land of limited contrast. In the north, a maritime plain parallels the Gulf of Aden coast, varying in width from roughly twelve kilometers in the west to as little as two kilometers in the east. Scrub-covered, semiarid, and generally drab, this plain, known as the Guban (scrub land), is crossed by broad, shallow watercourses that are beds of dry sand except in the rainy seasons. When the rains arrive, the vegetation, which is a combination of low bushes and grass clumps, is quickly renewed, and for a time the guban provides some grazing for nomad livestock.
Inland from the gulf coast, the plain rises to the precipitous northward-facing cliffs of the dissected highlands. These form the rugged Karkaar mountain ranges that extend from the northwestern border with Ethiopia eastward to the tip of the Horn of Africa, where they end in sheer cliffs at Caseyr. The general elevation along the crest of these mountains averages about 1,800 meters above sea level south of the port town of Berbera, and eastward from that area it continues at 1,800 to 2,100 meters almost to Caseyr. The country's highest point, Shimber Berris, which rises to 2,407 meters, is located near the town of Erigavo.
Southward the mountains descend, often in scarped ledges, to an elevated plateau devoid of perennial rivers. This region of broken mountain terrain, shallow plateau valleys, and usually dry watercourses is known to the Somalis as the Ogo.
In the Ogo's especially arid eastern part, the plateau—broken by several isolated mountain ranges—gradually slopes toward the Indian Ocean and in central Somalia constitutes the Mudug Plain. A major feature of this eastern section is the long and broad Nugaal Valley, with its extensive network of intermittent seasonal watercourses. The eastern area's population consists mainly of pastoral nomads. In a zone of low and erratic rainfall.
The western part of the Ogo plateau region is crossed by numerous shallow valleys and dry watercourses. Annual rainfall is greater than in the east, and there are flat areas of arable land that provide a home for dryland cultivators. Most important, the western area has permanent wells to which the predominantly nomadic population returns during the dry seasons. The western plateau slopes gently southward and merges imperceptibly into an area known as the Haud, a broad, undulating terrain that constitutes some of the best grazing lands for Somali nomads, despite the lack of appreciable rainfall more than half the year. Enhancing the value of the Haud are the natural depressions that during periods of rain become temporary lakes and ponds.
The Haud zone continues for more than sixty kilometers into Ethiopia, and the vast Somali Plateau, which lies between the northern Somali mountains and the highlands of southeast Ethiopia, extends south and eastward through Ethiopia into central and southwest Somalia. The portion of the Haud lying within Ethiopia was the subject of an agreement made during the colonial era permitting nomads from British Somaliland to pasture their herds there. After Somali independence in 1960, it became the subject of Somali claims and a source of considerable regional strife.
Southwestern Somalia is dominated by the country's only two permanent rivers, the Jubba and the Shabele. With their sources in the Ethiopian highlands, these rivers flow in a generally southerly direction, cutting wide valleys in the Somali Plateau as it descends toward the sea; the plateau's elevation falls off rapidly in this area. The adjacent coastal zone, which includes the lower reaches of the rivers and extends from the Mudug Plain to the Kenyan border, averages 180 meters above sea level.
The Jubba River enters the Indian Ocean at Kismaayo. Although the Shabeelle River at one time apparently also reached the sea near Merca, its course is thought to have changed in prehistoric times. The Shabeelle now turns southwestward near Balcad (about thirty kilometers north of Mogadishu) and parallels the coast for more than eighty-five kilometers. The river is perennial only to a point southwest of Mogadishu; thereafter it consists of swampy areas and dry reaches and is finally lost in the sand east of Jilib, not far from the Jubba River. During the flood seasons, the Shabeelle River may fill its bed to a point near Jilib and occasionally may even break through to the Jubba River farther south. Favorable rainfall and soil conditions make the entire riverine region a fertile agricultural area and the center of the country's largest sedentary population.
In most of northern, northeastern, and north-central Somalia, where rainfall is low, the vegetation consists of scattered low trees, including various acacias, and widely scattered patches of grass. This vegetation gives way to a combination of low bushes and grass clumps in the highly arid areas of the northeast and along the Gulf of Aden.
As elevations and rainfall increase in the maritime ranges of the north, the vegetation becomes denser. Aloes are common, and on the higher plateau areas of the Ogo are woodlands. At a few places above 1,500 meters, the remnants of juniper forests (protected by the state) and areas of candelabra euphorbia (a chandelier-type spiny plant) occur. In the more arid highlands of the northeast, Boswellia and Commiphora trees are sources, respectively, of the frankincense and myrrh for which Somalia has been known since ancient times.
A broad plateau encompassing the northern city of Hargeysa, which receives comparatively heavy rainfall, is covered naturally by woodland (much of which has been degraded by overgrazing) and in places by extensive grasslands. Parts of this area have been under cultivation since the 1930s, producing sorghum and maize; in the 1990s it constituted the only significant region of sedentary cultivation outside southwestern Somalia.
The Haud south of Hargeysa is covered mostly by a semiarid woodland of scattered trees, mainly acacias, underlain by grasses that include species especially favored by livestock as forage. As the Haud merges into the Mudug Plain in central Somalia, the aridity increases and the vegetation takes on a subdesert character. Farther southward the terrain gradually changes to semiarid woodlands and grasslands as the annual precipitation increases.
The region encompassing the Shabeelle and Jubba rivers is relatively well watered and constitutes the country's most arable zone. The lowland between the rivers supports rich pasturage. It features arid to subarid savanna, open woodland, and thickets that include frequently abundant underlying grasses. There are areas of grassland, and in the far southwest, near the Kenyan border, some dry evergreen forests are found.
Along the Indian Ocean from Mereeg, about 150 kilometers northeast of Mogadishu, southwestward to near Kismaayo lies a stretch of coastal sand dunes. This area is covered with scattered scrub and grass clumps where rainfall is sufficient. Overgrazing, particularly in the area between Mogadishu and Kismaayo, has resulted in the destruction of the protective vegetation cover and the gradual movement of the once-stationary dunes inland. Beginning in the early 1970s, efforts were made to stabilize these dunes by replanting.
Other vegetation includes plants and grasses found in the swamps into which the Shabeelle River empties most of the year and in other large swamps in the course of the lower Jubba River. Mangrove forests are found at points along the coast, particularly from Kismaayo to near the Kenyan border. Uncontrolled exploitation appears to have caused some damage to forests in that area. Other mangrove forests are located near Mogadishu and at a number of places along the northeastern and northern coasts.
Location: Eastern Africa, bordering the Gulf of Aden and the Indian Ocean, east of Ethiopia
Map references: Africa
Area:
total: 637,657 km²
land: 627,337 km²
water: 10,320 km²
Area - comparative: slightly smaller than Texas
Land boundaries:
total: 2,366 km
border countries: Djibouti 58 km, Ethiopia 1,626 km, Kenya 682 km
Coastline: 3,025 km
Maritime claims:
territorial sea: 200 nm (370.4 km)
Climate: principally desert; December to February - northeast monsoon, moderate temperatures in north and very hot in south; May to October - southwest monsoon, torrid in the north and hot in the south, irregular rainfall, hot and humid periods (tangambili) between monsoons
Terrain: mostly flat to undulating plateau rising to hills in north
Elevation extremes:
lowest point: Indian Ocean 0 m
highest point: Shimbiris 2,416 m
Natural resources: uranium and largely unexploited reserves of iron ore, tin, gypsum, bauxite, copper, salt
Land use:
arable land: 2%
permanent crops: 0%
permanent pastures: 69%
forests and woodland: 26%
other: 3% (1993 est.)
Irrigated land: 1,800 km² (1993 est.)
Natural hazards: recurring droughts; frequent dust storms over eastern plains in summer; floods during rainy season
Environment - current issues: famine; use of contaminated water contributes to human health problems; deforestation; overgrazing; soil erosion; desertification
Environment - international agreements:
party to: Endangered Species, Law of the Sea
signed, but not ratified: Marine Dumping, Nuclear Test Ban
Geography - note: strategic location on Horn of Africa along southern approaches to Bab el Mandeb and route through Red Sea and Suez Canal
