Wadi Howar (Wadi Howa) is a
wadi
Wadi ( ar, وَادِي, wādī), alternatively ''wād'' ( ar, وَاد), North African Arabic Oued, is the Arabic term traditionally referring to a valley. In some instances, it may refer to a wet (ephemeral) riverbed that contains water onl ...
in
Sudan
Sudan ( or ; ar, السودان, as-Sūdān, officially the Republic of the Sudan ( ar, جمهورية السودان, link=no, Jumhūriyyat as-Sūdān), is a country in Northeast Africa. It shares borders with the Central African Republic t ...
and
Chad
Chad (; ar, تشاد , ; french: Tchad, ), officially the Republic of Chad, '; ) is a landlocked country at the crossroads of North and Central Africa. It is bordered by Libya to the north, Sudan to the east, the Central African Republic ...
.
Geography
Originating in the
Ennedi Region
Ennedi Region was a former region of Chad. It was created in 2008 from the Ennedi Est Department and Ennedi Ouest Department of the former Borkou-Ennedi-Tibesti Region. The capital of the Ennedi region was Fada. In 2012 it was split into two ...
of
Chad
Chad (; ar, تشاد , ; french: Tchad, ), officially the Republic of Chad, '; ) is a landlocked country at the crossroads of North and Central Africa. It is bordered by Libya to the north, Sudan to the east, the Central African Republic ...
''Wadi Howar'' runs through the Sudanese states of
North Darfur
North Darfur State ( ar, ولاية شمال دارفور 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 a ...
and
Northern to join the Nile north of the
great bend
Great Bend is a city in and the county seat of Barton County, Kansas, United States. It is named for its location at the point where the course of the Arkansas River bends east then southeast. As of the 2020 census, the population of the ci ...
opposite
Old Dongola
Old Dongola (Old Nubian: ⲧⲩⲛⲅⲩⲗ, ''Tungul''; ar, دنقلا العجوز, ''Dunqulā al-ʿAjūz'') is a deserted town in what is now Northern State, Sudan, located on the east bank of the Nile opposite the Wadi Howar. An important c ...
. 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 north-eastern Sahara Desert, from eastern Libya to the Western Desert of Egypt and far northwestern Sudan. On medieval maps, its use predates t ...
, 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, , Bohairic , lg, Kiira , Nobiin language, Nobiin: Áman Dawū is a major north-flowing river in northeastern Africa. It flows into the Mediterranean Sea. The Nile is the longest river in Africa and has historically been considered ...
during the
Neolithic Subpluvial
The African humid period (AHP) (also known by other names) is a climate period in Africa during the late Pleistocene and Holocene geologic epochs, when northern Africa was wetter than today. The covering of much of the Sahara desert by grasses, ...
from about 9500 to 4500 years ago. At that time
Savanna
A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to ...
fauna and cattle-herders occupied this region and the southern edge of the
Sahara
, photo = Sahara real color.jpg
, photo_caption = The Sahara taken by Apollo 17 astronauts, 1972
, map =
, map_image =
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was some 500 km further north than it is today.
[ When the Sahara underwent ]desertification
Desertification is a type of land degradation in drylands in which biological productivity is lost due to natural processes or induced by human activities whereby fertile areas become increasingly arid. It is the spread of arid areas caused by ...
between 6000 and 4000 years ago, the wadi first became a chain of freshwater lakes and marshes, as shown by Ptolemy's world map
The Ptolemy world map is a map of the world known to Greco-Roman societies in the 2nd century. It is based on the description contained in Ptolemy's book ''Geography'', written . Based on an inscription in several of the earliest surviving manusc ...
, 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.
]
See also
* African humid period
The African humid period (AHP) (also known by other names) is a climate period in Africa during the late Pleistocene and Holocene geologic epochs, when northern Africa was wetter than today. The covering of much of the Sahara desert by grasses, ...
* Lake Ptolemy
Lake Ptolemy is a former lake in Sudan. This lake formed during the Holocene in the Darfur region, during a time when the monsoon over Africa was stronger. The existence of the lake is dated between about 9,100–2,400 years before present. This ...
References
{{Authority control
Howar
Nile
Rivers of Sudan
Rivers of Chad
International rivers of Africa
Chad–Sudan border
North Darfur