Sudan

1 LOCATION AND SIZE

Sudan is located in northeast Africa on the western border of the Red Sea. It is the largest country in Africa and shares borders with Egypt, Libya, Chad, the Central African Republic, Uganda, Kenya, Ethiopia, and Eritrea. With an area of about 2,505,810 square kilometers (967,499 square miles), it is slightly more than one-fourth the size of the United States. Sudan is divided into twenty-six states.

2 TERRITORIES AND DEPENDENCIES

Sudan has no outside territories or dependencies.

3 CLIMATE

Sudan has an equatorial climate. The northern plains and desert region are hot and dry with maximum temperatures reaching 42°C (108°F) from March through June. November through February are the coolest months, with average temperatures of 32°C (90°F) and nighttime lows of 4°C (40°F). Average temperatures in the central and southern regions are 27°C (80°F) and 29°C (85°F) respectively.

Rainfall increases from north to south. In the north, annual rainfall totals about 10 centimeters (4 inches). The southern regions receive 76 to 127 centimeters (30 to 50 inches) of rain during the long rainy season; as a result, these areas support a rich variety of tall grasses, shrubs, and trees. The lush vegetation in the south contrasts sharply with the deserts of Northern Province, where the occasional rains vanish in the parched sand and vast areas are devoid of both vegetation and people.

4 TOPOGRAPHIC REGIONS

Sudan is an immense, sparsely populated plain, with plateaus or mountains near the borders in the west, the southeast, and along the Red Sea coast in the northeast.

The most prevalent landscape is semiarid savannah, a mixture of short grasses, scattered brush, and short trees.

Narrow belts of irrigated cropland, no more than a few miles wide, bisect the northern savannah and deserts along the main Nile River; these farmlands also run along the White Nile, the Blue Nile, and the Atbara Rivers. They contrast sharply with the arid savannah or barren desert which is just beyond the limits of irrigation. Only 5 percent of the land in Sudan is arable; of the remaining terrain, 24 percent is meadows and pastures, 20 percent is forest and woodland, and 51 percent is semiarid desert.

5 OCEANS AND SEAS

Seacoast and Undersea Features

Sudan has an eastern coast on the Red Sea, which is a narrow, landlocked sea that separates Africa from the Arabian Peninsula. In the north, it links to the Mediterranean through the Gulf of Suez and the Suez Canal. In the south, the sea links to the Gulf of Aden and the Arabian Sea through the strait of Bab el Mandeb. The Red Sea is therefore a major shipping route between the Mediterranean Sea and the Gulf of Aden. At its widest point, it is only 326 kilometers (205 miles). The Red Sea is rather deep, with an average depth of 500 meters (1,640 feet). It reaches a maximum depth of 2,000 meters (6,562 feet), and it features red coral reefs and extensive coral gardens.

Sea Inlets and Straits

Natural harbors of the Red Sea exist at Port Sudan (Bur Sudan) and Sawākin.

6 INLAND LAKES

Sudan has very few lakes. The largest ones are artificial, resulting from dams on the Blue Nile and Upper Nile Rivers. The backwaters of the Aswan Dam in Egypt created Lake Nubia, the largest lake in Sudan. The lake begins in Egypt and extends into Sudan as far as the northern terminus of the Sudanese railway at Wadi Halfa. Its total surface area during the wet season is 968 square kilometers (373 square miles).

7 RIVERS AND WATERFALLS

With a total length of about 6,693 kilometers (4,160 miles), the Nile is the longest river in the world, although other rivers carry more water. The Nile is a combination of the White Nile, which originates in Lake Victoria in Uganda and Tanzania, and the Blue Nile, which originates in Ethiopia. These rivers meet in Sudan near the city of Khartoum.

From the confluence of the White and Blue Nile Rivers near Khartoum, the Upper Nile winds northward through this desert area for a distance of 1,287 kilometers (800 miles) inside Sudan. It provides the only water for the narrow strips of cultivation along the riverbanks. Virtually no rain falls in the area between Atbara and the Egyptian frontier at Wadi Halfa; Wadi Halfa is often completely rainless for years at a time. The settlements along the Nile depend on various types of irrigation or periodic flooding for their livelihood.

Within Sudan, the Blue Nile experiences seasonal flooding caused by torrential rains in the Ethiopian highland regions. Half of the people of Sudan are dependent on waters from these floods. During flood times, the flow of the Blue Nile may be sixty times greater than that of its low-water period.

An important tributary to the Upper Nile is the Atbara River, similar in seasonal behavior to the Blue Nile and also originating in the mountains of Ethiopia. It traverses northwest across eastern Sudan and empties into the Nile at the town of Atbara. The gradient of the Nile from Khartoum to Wadi Halfa on the northern border of Sudan is very steep. Along this lower reach are five of the Nile's six cataract areas of swift, rough water.

The Nile crosses the northern border of Sudan into Egypt and eventually empties into the Mediterranean Sea.

All perennial streams of significant size in Sudan are part of the Nile system. There are also numerous wadis, or intermittent streams, which flow only part of the year. Some drain into the Nile during the rainy season and stand empty at other times. Others drain into swamps that have no outlet to a river or simply disappear into the sands of an inland basin during the dry months. For example, the Wadi Howar and the Wadi Al-Ku, both originating in the Teiga Plateau region, disappear into the desert. Another stream of similar origin, the Wadi Azum, eventually reaches the Lake Chad drainage system to the west. Some of these intermittent streams carry large amounts of water during the rainy season and support local areas of agriculture. The Mareb, also known as the Gash or Al-Qāsh in Sudan, and the Baraka River flow into northeast Sudan from the Eritrean highlands during the months of July, August, and September. The Mareb River provides water for important irrigation schemes north of Kassalā and the Baraka feeds the Tawkar delta near the Red Sea coast. The Bahr el Arab in southwestern Sudan is another important seasonal river.

Permanent swamps surround the river systems in the southern provinces and Upper Nile, covering about 129,500 square kilometers (50,000 square miles), where there is an excess of water for most of the year. This phenomenon is best characterized by the Sudd, a vast region of swamps and marshes covering an area of about 7,770 square kilometers (3,000 square miles) and extending from Boma National Park several hundred miles northwestward to the Al-Ghazāl River, ending at the Machar Marshes near the Ethiopian border. The vast swamp and marsh area is as monotonous as the featureless plains farther north, but there is considerable variety of terrain and vegetation in the uplands south of the swamps, particularly near the Uganda and Kenya borders. The largest swamp in the Sudd, Badigeru Swamp, is located between the Al-Jabal and Boma National Park. Lotagipi Swamp is located in the southeast corner of Sudan, at the junction with Kenya and Ethiopia.

8 DESERTS

A line running east to Atbara and Port Sudan from the western frontier at 16°N latitude defines the approximate southern limit of desert, which covers the northern quarter of Sudan. The Libyan Desert extends into Sudan from the northwest. In the northeast, the Nubian Desert covers the area between the Nile and the Red Sea Hills. These deserts are part of the larger Sahara Desert.

The desert west of the Nile supports only a few Arab nomads who cover great expanses of the parched country in search of grazing land for their camels, sheep, or goats. They usually find pastures in the south, where a little rain occurs during most years and grass springs to life. Water is available only in scattered oases, such as Al Atrun in the western desert and Well No. 6 on the railway between Wadi Halfa and Abu Hamand. Terrain in this northern desert consists of broad areas of sand and flintrock with occasional hills of basalt, granite, and limestone, often surrounded by banks of sand deposited by the wind.

9 FLAT AND ROLLING TERRAIN

The topography of the country outside the mountains and the Nile valley is basically a flat plain extending some 804 to 965 kilometers (500 to 600 miles) from east to west and more than 1,609 kilometers (1,000 miles) from north to south. It is a part of the broad savannah belt that begins at the southern edge of the Sahara Desert and extends across the African continent. For hundreds of square kilometers the only features relieving the monotony of the Sudanese plain are low rolling hills (sometimes referred to locally as mountains) or extensive sand dunes created thousands of years ago and partially or entirely fixed by vegetation. Soils are composed mainly of clay, much of which is impermeable and difficult to cultivate, or of sand that contains little clay or humus (organic matter).

10 MOUNTAINS AND VOLCANOES

Sudan has four mountain or upland zones. To the northeast near the coast lie the Red Sea Hills. In the west are the Marra, a mountain range that slopes to the border with Chad, and in central Sudan south of El Obeid are the Nuba Mountains, a relatively minor system that rises above the clay plains. The fourth zone includes the Imatong and Dongotona Mountains in the extreme south along the Uganda border.

The Red Sea Hills are eroded outcroppings of base rock rising from a narrow coastal plain. The abruptness of their eastern slope gives rise to gushing torrents during winter rains that are blown in from the sea. The western slopes incline more slowly toward the Nile and receive only light summer rains. North of the Atbara-Port Sudan railway, the hills extend into the desert and are bare of vegetation except in the valleys. South of the railway, however, increased rainfall permits the growth of a few trees and thorny shrubs. The area is inhospitable and supports only semi-nomadic herders, who also cultivate hardy varieties of millet in the wetter valleys. They move their flocks laterally across the mountains or to higher or lower altitudes, depending upon the vagaries of the rainfall at various elevations. The highest of the Red Sea Hills are above 2,133 meters (7,000 feet).

The only major mountain range in western Sudan, the Marra, stands near the city of El Fasher, rising above 3,048 meters (10,000 feet) in elevation. The Marra is of volcanic origin and its valleys are relatively fertile. The upper elevations receive a slightly higher rainfall than the surrounding plains and the relatively rich soil of the valley is more productive. Some of the rocks and peaks have a sculptured appearance resulting from the action of the rains upon the soft volcanic rock. Streams deposit much of the eroded rock on the desert floor below, but on the higher hillsides, artificial terraces of ancient origin retain topsoil and water. Although cultivation is generally dependent upon the seasonal rains, some valleys and terraces are irrigated with water from small perennial mountain streams.

The Nuba Mountains of central Sudan are scattered granitic masses, rising as much as 914 meters (3,000 feet) above a level clay plain. They are covered in many areas by variations of savannah vegetation. Some slopes were once terraced and then abandoned by subsistence farmers. Water is not as scarce in the mountains as in the surrounding plains. Wells are numerous in the open valleys, and a few short mountain streams continue to flow throughout the year.

The Imatong and Dongotona Mountains stand in the extreme south, with the lower Didinga Hills flanking them to the east. The Imatongs are the highest mountains in Sudan, with peaks above 3,048 meters (10,000 feet) including Mount Kinyeti, the highest point in the country, which rises to a height of 3,187 meters (10,456 feet). The Dongotona Mountains, lying east of the Imatongs, reach a maximum height of about 2,529 meters (8,300 feet). Both mountain chains have a considerable coverage of rainforest.

11 CANYONS AND CAVES

There are no major caves or canyons in Sudan.

12 PLATEAUS AND MONOLITHS

Plateau-like formations characterize the mountainous areas and their foothills and, therefore, tend to rim the country, serving as watersheds for the great Nile basin drainage. The best examples are found in the large Teiga Plateau north of the Marra in the west and the extensive Ironstone Plateau in the southwest. Near the Imatongs and Dongotona Mountains area in the southeast, on the border with Ethiopia, sits the Boma Plateau, the site of a national park. West of this region, north of the mountains and northeast of Ironstone Plateau, lower plateaus slope generally northward toward the Sudd. In the north, the Libyan Desert runs across the Jebel Abyad Plateau. Along the Red Sea coast in the northeast, there are also some smaller plateaus.

13 MAN-MADE FEATURES

There is an extensive system of dams and reservoirs built throughout the course of the Nile River. These dams serve to control flood waters, irrigate agriculture lands, provide drinking water, and generate hydroelectric power. For instance, in Sudan, the Sannar Dam on the Blue Nile allows for irrigation of the Al-Jazirah plain and produces hydroelectric power. The Ar-Rusayris Dam, also on the Blue Nile, helps contain water from Lake Nassar (at the Egyptian border) for use in Sudan.

14 FURTHER READING

Books

Africa South of the Sahara 2002: Sudan. London: Europa Publishers, 2001.

Lobban, Jr. Richard A., Robert S. Kramer, and Carolyn Fluehr-Lobban. Historical Dictionary of the Sudan. 3rd ed. Meutchen, NJ: Scarecrow Press, 2002.

Moorehead, Alan. The Blue Nile. New York: HarperTrade, 2000.

Williams, Martin A. J., and D. A. Adamson. Land Between Two Niles: Quaternary Geology and Biology of the Central Sudan . Salem, NH: MBS, 1982.

Web Sites

The Embassy of Republic of Sudan in London. http://www.sudan-embassy.co.uk (accessed May 6, 2003).