Wadi Howar (Wadi Howa or Yellow Nile) is a

wadi Wadi ( ; ) is a river valley or a wet (ephemerality, ephemeral) Stream bed, riverbed that contains water only when heavy rain occurs. Wadis are located on gently sloping, nearly flat parts of deserts; commonly they begin on the distal portion ...

Sudan Sudan, officially the Republic of the Sudan, is a country in Northeast Africa. It borders the Central African Republic to the southwest, Chad to the west, Libya to the northwest, Egypt to the north, the Red Sea to the east, Eritrea and Ethiopi ...

and

Chad Chad, officially the Republic of Chad, is a landlocked country at the crossroads of North Africa, North and Central Africa. It is bordered by Libya to Chad–Libya border, the north, Sudan to Chad–Sudan border, the east, the Central Afric ...

Geography

Originating in the Ennedi Region of

''Wadi Howar'' runs through the Sudanese states of

North Darfur North Darfur State ( Wilāyat Šamāl Dārfūr; ''Shamal Darfor'') is one of the wilayat or states of Sudan. It is one of the five states composing the Darfur region. It has an area of 296,420 km2 and an estimated population of approximat ...

and Northern to join the Nile north of the great bend opposite

Old Dongola Old Dongola ( Old Nubian: ⲧⲩⲛⲅⲩⲗ, ''Tungul''; , ''Dunqulā al-ʿAjūz'') is a deserted Nubian town in what is now Northern State, Sudan, located on the east bank of the Nile opposite the Wadi Howar. An important city in medieval Nub ...

. Stretching over 1100 km in west–east direction across the southern fringes of the

Libyan Desert The Libyan Desert (not to be confused with the Libyan Sahara) is a geographical region filling the northeastern Sahara Desert, from eastern Libya to the Western Desert (Egypt), Western Desert of Egypt and far northwestern Sudan. On medieval m ...

, it ordinarily receives 25 mm of rainfall per year.

Holocene period

''Wadi Howar'' is the remnant of the ancient ''Yellow Nile'', a tributary of the

Nile The Nile (also known as the Nile River or River Nile) is a major north-flowing river in northeastern Africa. It flows into the Mediterranean Sea. The Nile is the longest river in Africa. It has historically been considered the List of river sy ...

during the African humid period from about 9500 to 4500 years ago. At that time,

savanna A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) biome and ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach th ...

fauna and cattle

herder A herder is a pastoralism, pastoral worker responsible for the care and management of a herd or flock of domestic animals, usually on extensive management, open pasture. It is particularly associated with nomadic pastoralism, nomadic or transhuma ...

s occupied this region and the southern edge of the

Sahara The Sahara (, ) is a desert spanning across North Africa. With an area of , it is the largest hot desert in the world and the list of deserts by area, third-largest desert overall, smaller only than the deserts of Antarctica and the northern Ar ...

was some further north than it is today. When the Sahara underwent

desertification Desertification is a type of gradual land degradation of Soil fertility, fertile land into arid desert due to a combination of natural processes and human activities. The immediate cause of desertification is the loss of most vegetation. This i ...

between 6000 and 4000 years ago, the

first became a chain of freshwater lakes and marshes, as shown by Ptolemy's world map, then it became extinct about 2000 years ago.

Archaeology

Abundant prehistoric sites certify ''Wadi Howar'' as a once ecologically favoured area of settlement and a communication route between the inner regions of Africa and the Nile Valley. The hitherto most thoroughly investigated archaeological site in the wadi is Gala Abu Ahmed.

References

{{Authority control Howar Nile Rivers of Sudan Rivers of Chad International rivers of Africa Chad–Sudan border North Darfur

Geography

Holocene period

Archaeology

See also

References