, photo = Sahara real color.jpg , photo_caption = The Sahara taken by

Apollo 17 Apollo 17 (December 7–19, 1972) was the final mission of NASA's Apollo program, the most recent time humans have set foot on the Moon or traveled beyond low Earth orbit. Commander Gene Cernan and Lunar Module Pilot Harrison Schmitt walke ...

astronauts, 1972 , map = , map_image = , location = , country = , country1 = , country2 = , country3 = , country4 = , country5 = , country6 = , country7 = , country8 = , country9 = , country10 = (

disputed Controversy is a state of prolonged public dispute or debate, usually concerning a matter of conflicting opinion or point of view. The word was coined from the Latin ''controversia'', as a composite of ''controversus'' – "turned in an opposite d ...

) , region = , state = , district = , city = , relief = , label = , label_position = , coordinates = , coordinates_ref = , elevation = , elevation_m = , elevation_ft = , elevation_ref = , length = , length_mi = , length_km = 4,800 , length_orientation = , length_note = , width = , width_mi = , width_km = 1,800 , width_orientation = , width_note = , area = , area_mi2 = , area_km2 = 9,200,000 , depth = , depth_ft = , depth_m = , type = , age = , border = , topo = , traversed = , river = , footnotes = , map_size= The Sahara (, ) is a

desert A desert is a barren area of landscape where little precipitation occurs and, consequently, living conditions are hostile for plant and animal life. The lack of vegetation exposes the unprotected surface of the ground to denudation. About on ...

on the African continent. With an area of , it is the largest hot desert in the world and the third-largest desert overall, smaller only than the deserts of

Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest cont ...

and the northern

Arctic The Arctic ( or ) is a polar regions of Earth, polar region located at the northernmost part of Earth. The Arctic consists of the Arctic Ocean, adjacent seas, and parts of Canada (Yukon, Northwest Territories, Nunavut), Danish Realm (Greenla ...

. The name "Sahara" is derived from the Arabic word for "desert" in the feminine irregular form, the singular ( ), plural ( ), (), (), (). The desert comprises much of

North Africa North Africa, or Northern Africa is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region, and it is sometimes defined as stretching from the Atlantic shores of Mauritania in ...

, excluding the fertile region on the

Mediterranean Sea The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on ...

coast, the Atlas Mountains of the

Maghreb The Maghreb (; ar, الْمَغْرِب, al-Maghrib, lit=the west), also known as the Arab Maghreb ( ar, المغرب العربي) and Northwest Africa, is the western part of North Africa and the Arab world. The region includes Algeria, ...

, and the Nile Valley in

Egypt Egypt ( ar, مصر , ), officially the Arab Republic of Egypt, is a List of transcontinental countries, transcontinental country spanning the North Africa, northeast corner of Africa and Western Asia, southwest corner of Asia via a land bridg ...

and the

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 ...

. It stretches from the

Red Sea The Red Sea ( ar, البحر الأحمر - بحر القلزم, translit=Modern: al-Baḥr al-ʾAḥmar, Medieval: Baḥr al-Qulzum; or ; Coptic: ⲫⲓⲟⲙ ⲛ̀ϩⲁϩ ''Phiom Enhah'' or ⲫⲓⲟⲙ ⲛ̀ϣⲁⲣⲓ ''Phiom ǹšari''; ...

in the east and the Mediterranean in the north to the

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...

in the west, where the landscape gradually changes from desert to coastal plains. To the south it is bounded by the Sahel, a belt of semi-arid tropical savanna around the

Niger River The Niger River ( ; ) is the main river of West Africa, extending about . Its drainage basin is in area. Its source is in the Guinea Highlands in south-eastern Guinea near the Sierra Leone border. It runs in a crescent shape through Mal ...

valley and the

Sudan region Sudan is the geographical region to the south of the Sahara, stretching from Western Africa to Central and Eastern Africa. The name derives from the Arabic ' (), or "the lands of the Blacks", referring to West Africa and northern Central Afri ...

sub-Saharan Africa Sub-Saharan Africa is, geographically, the area and regions of the continent of Africa that lies south of the Sahara. These include West Africa, East Africa, Central Africa, and Southern Africa. Geopolitically, in addition to the List of sov ...

. The Sahara can be divided into several regions, including the western Sahara, the central

Ahaggar Mountains The Hoggar Mountains ( ar, جبال هقار, Berber: ''idurar n Ahaggar'') are a highland region in the central Sahara in southern Algeria, along the Tropic of Cancer. The mountains cover an area of approximately 550,000 km. Geography This ...

, the Tibesti Mountains, the Aïr Mountains, the Ténéré desert, and 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 ...

. For several hundred thousand years, the Sahara has alternated between desert and savanna grassland in a 20,000-year cycle caused by the precession of Earth's axis as it rotates around the Sun, which changes the location of the North African monsoon.

Geography

The Sahara covers large parts of

Algeria ) , image_map = Algeria (centered orthographic projection).svg , map_caption = , image_map2 = , capital = Algiers , coordinates = , largest_city = capital , relig ...

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 ...

Libya Libya (; ar, ليبيا, Lībiyā), officially the State of Libya ( ar, دولة ليبيا, Dawlat Lībiyā), is a country in the Maghreb region in North Africa. It is bordered by the Mediterranean Sea to the north, Egypt to the east, Suda ...

Mali Mali (; ), officially the Republic of Mali,, , ff, 𞤈𞤫𞤲𞥆𞤣𞤢𞥄𞤲𞤣𞤭 𞤃𞤢𞥄𞤤𞤭, Renndaandi Maali, italics=no, ar, جمهورية مالي, Jumhūriyyāt Mālī is a landlocked country in West Africa. Ma ...

, Mauritania,

Morocco Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to A ...

Niger ) , official_languages = , languages_type = National languagesWestern Sahara,

and

Tunisia ) , image_map = Tunisia location (orthographic projection).svg , map_caption = Location of Tunisia in northern Africa , image_map2 = , capital = Tunis , largest_city = capital , ...

. It covers , amounting to 31% of Africa. If all areas with a mean annual precipitation of less than 250 mm were included, the Sahara would be . It is one of three distinct physiographic provinces of the African massive physiographic division. Sahara is so large and bright that, in theory, it could be detected from other stars as a surface feature of Earth, with near-current technology. The Sahara is mainly rocky hamada (stone plateaus); ergs (sand seas – large areas covered with sand

dune A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, f ...

s) form only a minor part, but many of the

sand dune A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, f ...

s are over high.

Wind Wind is the natural movement of air or other gases relative to a planet's surface. Winds occur on a range of scales, from thunderstorm flows lasting tens of minutes, to local breezes generated by heating of land surfaces and lasting a few ...

or rare rainfall shape the desert features: sand dunes, dune fields, sand seas, stone plateaus, gravel plains (''reg''), dry valleys (''wadi''),

dry lake A dry lake bed, also known as a playa, is a basin or depression that formerly contained a standing surface water body, which disappears when evaporation processes exceeds recharge. If the floor of a dry lake is covered by deposits of alkaline c ...

s (''oued''), and salt flats (''shatt'' or ''chott''). Unusual landforms include the Richat Structure in Mauritania. Several deeply dissected mountains, many volcanic, rise from the desert, including the Aïr Mountains,

, Saharan Atlas, Tibesti Mountains, Adrar des Iforas, and the Red Sea Hills. The highest peak in the Sahara is Emi Koussi, a shield volcano in the

Tibesti The Tibesti Mountains are a mountain range in the central Sahara, primarily located in the extreme north of Chad, with a small portion located in southern Libya. The highest peak in the range, Emi Koussi, lies to the south at a height of an ...

range of northern Chad. The central Sahara is hyperarid, with sparse vegetation. The northern and southern reaches of the desert, along with the highlands, have areas of sparse grassland and

desert shrub Deserts and xeric shrublands are a biome defined by the World Wide Fund for Nature. Deserts and xeric (ancient Greek xērós, “dry") shrublands form the largest terrestrial biome, covering 19% of Earth's land surface area. Ecoregions in this h ...

, with trees and taller shrubs in

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 ...

s, where moisture collects. In the central, hyperarid region, there are many subdivisions of the great desert:

Tanezrouft The Tanezrouft ( ar, تنزروفت) is a natural region located along the borders of Algeria and Mali, west of the Hoggar Mountains. Along with the Libyan Desert it is one of the most desolate and most arid parts of the Sahara Desert. This area ha ...

, the Ténéré, the

, the Eastern Desert, the

Nubian Desert The Nubian Desert ( ar, صحراء النوبة, ''Şaḩrā’ an Nūbyah'') is in the eastern region of the Sahara Desert, spanning approximately 400,000 km2 of northeastern Sudan and northern Eritrea, between the Nile and the Red Sea ...

and others. These extremely arid areas often receive no rain for years. To the north, the Sahara skirts the

in Egypt and portions of Libya, but in Cyrenaica and the

, the Sahara borders the Mediterranean forest, woodland, and scrub eco-regions of northern Africa, all of which have a

Mediterranean climate A Mediterranean climate (also called a dry summer temperate climate ''Cs'') is a temperate climate sub-type, generally characterized by warm, dry summers and mild, fairly wet winters; these weather conditions are typically experienced in the ...

characterized by hot summers and cool and rainy winters. According to the botanical criteria of Frank White and geographer Robert Capot-Rey, the northern limit of the Sahara corresponds to the northern limit of date palm cultivation and the southern limit of the range of esparto, a

grass Poaceae () or Gramineae () is a large and nearly ubiquitous family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos and the grasses of natural grassland and species cultivated in lawns a ...

typical of the Mediterranean climate portion of the Maghreb and

Iberia The Iberian Peninsula (), ** * Aragonese language, Aragonese and Occitan language, Occitan: ''Peninsula Iberica'' ** ** * french: Péninsule Ibérique * mwl, Península Eibérica * eu, Iberiar penintsula also known as Iberia, is a pe ...

. The northern limit also corresponds to the

isohyet A contour line (also isoline, isopleth, or isarithm) of a function of two variables is a curve along which the function has a constant value, so that the curve joins points of equal value. It is a plane section of the three-dimensional grap ...

of annual precipitation. To the south, the Sahara is bounded by the Sahel, a belt of dry tropical savanna with a summer rainy season that extends across Africa from east to west. The southern limit of the Sahara is indicated botanically by the southern limit of ''

Cornulaca monacantha ''Cornulaca monacantha'' is a species of flowering plant in the genus '' Cornulaca'', that is now included in the family Amaranthaceae, (formerly Chenopodiaceae). It is a desert plant found in the Middle East and the Sahara, and the southern end ...

'' (a drought-tolerant member of the Chenopodiaceae), or northern limit of ''

Cenchrus biflorus ''Cenchrus biflorus'' is a species of annual grass in the family Poaceae. Common names include Indian sandbur, ''Bhurat'' or ''Bhurut'' in India, ''Haskaneet'' in Sudan, ''Aneeti'' in the Arabic dialect of Mauritania, ''K 'arangiya'' in the Haus ...

'', a

typical of the Sahel. According to climatic criteria, the southern limit of the Sahara corresponds to the isohyet of annual precipitation (this is a long-term average, since

precipitation In meteorology, precipitation is any product of the condensation of atmospheric water vapor that falls under gravitational pull from clouds. The main forms of precipitation include drizzle, rain, sleet, snow, ice pellets, graupel and hail. ...

varies annually). Important cities located in the Sahara include Nouakchott, the capital of Mauritania; Tamanrasset, Ouargla, Béchar,

Hassi Messaoud Hassi Messaoud ( ar, حاسي مسعود) is a town in Ouargla Province, eastern Algeria, located southeast of Ouargla. As of 2008 it had a population of 45,147 people, up from 40,360 in 1998, and an annual population growth rate of 1.1%, the low ...

, Ghardaïa, and

El Oued El Oued ( ar, اﻟﻮادي, ber, Suf meaning ''the River''), Souf or Oued Souf is a city, and the capital of El Oued Province, in Algeria. The oasis town is watered by an underground river, hence its name is El Oued which enables date palm culti ...

in Algeria;

Timbuktu Timbuktu ( ; french: Tombouctou; Koyra Chiini: ); tmh, label=Tuareg, script=Tfng, ⵜⵏⴱⴾⵜ, Tin Buqt a city in Mali, situated north of the Niger River. The town is the capital of the Tombouctou Region, one of the eight administrativ ...

in Mali; Agadez in Niger; Ghat in Libya; and Faya-Largeau in Chad.

Climate

The Sahara is the world's largest

hot desert A desert is a barren area of landscape where little precipitation occurs and, consequently, living conditions are hostile for plant and animal life. The lack of vegetation exposes the unprotected surface of the ground to denudation. About one ...

. It is located in the horse latitudes under the

subtropical ridge The horse latitudes are the latitudes about 30 degrees north and south of the Equator. They are characterized by sunny skies, calm winds, and very little precipitation. They are also known as subtropical ridges, or highs. It is a high-press ...

, a significant belt of semi-permanent subtropical warm-core high pressure where the air from the upper troposphere usually descends, warming and drying the lower troposphere and preventing cloud formation. The permanent absence of clouds allows unhindered light and thermal radiation. The stability of the atmosphere above the desert prevents any convective overturning, thus making rainfall virtually non-existent. As a consequence, the weather tends to be sunny, dry and stable with a minimal chance of rainfall. Subsiding, diverging, dry air masses associated with subtropical high-pressure systems are extremely unfavorable for the development of convectional showers. The subtropical ridge is the predominant factor that explains the hot desert climate (

Köppen climate classification The Köppen climate classification is one of the most widely used climate classification systems. It was first published by German-Russian climatologist Wladimir Köppen (1846–1940) in 1884, with several later modifications by Köppen, nota ...

''BWh'') of this vast region. The descending airflow is the strongest and the most effective over the eastern part of the Great Desert, in the Libyan Desert: this is the sunniest, driest and the most nearly "rainless" place on the planet, rivaling the Atacama Desert, lying in

Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the eas ...

and

Peru , image_flag = Flag of Peru.svg , image_coat = Escudo nacional del Perú.svg , other_symbol = Great Seal of the State , other_symbol_type = National seal , national_motto = "Firm and Happy f ...

. The rainfall inhibition and the dissipation of cloud cover are most accentuated over the eastern section of the Sahara rather than the western. The prevailing air mass lying above the Sahara is the continental tropical (cT) air mass, which is hot and dry. Hot, dry air masses primarily form over the North-African desert from the heating of the vast continental land area, and it affects the whole desert during most of the year. Because of this extreme heating process, a

thermal low Thermal lows, or heat lows, are non- frontal low-pressure areas that occur over the continents in the subtropics during the warm season, as the result of intense heating when compared to their surrounding environments.Glossary of Meteorology (20 ...

is usually noticed near the surface, and is the strongest and the most developed during the summertime. The Sahara High represents the eastern continental extension of the

Azores High The Azores High also known as North Atlantic (Subtropical) High/Anticyclone or the Bermuda-Azores High, is a large subtropical semi-permanent centre of high atmospheric pressure typically found south of the Azores in the Atlantic Ocean, at the H ...

, centered over the North Atlantic Ocean. The subsidence of the Sahara High nearly reaches the ground during the coolest part of the year, while it is confined to the upper troposphere during the hottest periods. The effects of local surface low pressure are extremely limited because upper-level subsidence still continues to block any form of air ascent. Also, to be protected against rain-bearing weather systems by the atmospheric circulation itself, the desert is made even drier by its geographical configuration and location. Indeed, the extreme aridity of the Sahara is not only explained by the subtropical high pressure: the Atlas Mountains of Algeria, Morocco and Tunisia also help to enhance the aridity of the northern part of the desert. These major mountain ranges act as a barrier, causing a strong rain shadow effect on the leeward side by dropping much of the humidity brought by atmospheric disturbances along the

polar front In meteorology, the polar front is the weather front boundary between the polar cell and the Ferrel cell around the 60° latitude, near the polar regions, in both hemisphere. At this boundary a sharp gradient in temperature occurs between the ...

which affects the surrounding Mediterranean climates. The primary source of rain in the Sahara is the

Intertropical Convergence Zone The Intertropical Convergence Zone (ITCZ ), known by sailors as the doldrums or the calms because of its monotonous windless weather, is the area where the northeast and the southeast trade winds converge. It encircles Earth near the thermal ...

, a continuous belt of low-pressure systems near the equator which bring the brief, short and irregular

rainy season The rainy season is the time of year when most of a region's average annual rainfall occurs. Rainy Season may also refer to: * ''Rainy Season'' (short story), a 1989 short horror story by Stephen King * "Rainy Season", a 2018 song by Monni * '' ...

to the Sahel and southern Sahara. Rainfall in this giant desert has to overcome the physical and atmospheric barriers that normally prevent the production of precipitation. The harsh climate of the Sahara is characterized by: extremely low, unreliable, highly erratic rainfall; extremely high sunshine duration values; high temperatures year-round; negligible rates of

relative humidity Humidity is the concentration of water vapor present in the air. Water vapor, the gaseous state of water, is generally invisible to the human eye. Humidity indicates the likelihood for precipitation, dew, or fog to be present. Humidity dep ...

; a significant diurnal temperature variation; and extremely high levels of potential evaporation which are the highest recorded worldwide.

Temperature

The sky is usually clear above the desert, and the

sunshine duration Sunshine duration or sunshine hours is a climatological indicator, measuring duration of sunshine in given period (usually, a day or a year) for a given location on Earth, typically expressed as an averaged value over several years. It is a gen ...

is extremely high everywhere in the Sahara. Most of the desert has more than 3,600 hours of bright sunshine per year (over 82% of daylight hours), and a wide area in the eastern part has over 4,000 hours of bright sunshine per year (over 91% of daylight hours). The highest values are very close to the theoretical maximum value. A value of 4300 hours (98%) of the time would be recorded in

Upper Egypt Upper Egypt ( ar, صعيد مصر ', shortened to , , locally: ; ) is the southern portion of Egypt and is composed of the lands on both sides of the Nile that extend upriver from Lower Egypt in the north to Nubia in the south. In ancient E ...

( Aswan,

Luxor Luxor ( ar, الأقصر, al-ʾuqṣur, lit=the palaces) is a modern city in Upper (southern) Egypt which includes the site of the Ancient Egyptian city of ''Thebes''. Luxor has frequently been characterized as the "world's greatest open-a ...

) and in the Nubian Desert ( Wadi Halfa). The annual average direct solar irradiation is around 2,800 kWh/(m² year) in the Great Desert. The Sahara has a huge potential for solar energy production. Algeria Sahara Desert Photo From Drone 5

Algeria Sahara Desert Photo From Drone 5

The high position of the Sun, the extremely low relative humidity, and the lack of

vegetation Vegetation is an assemblage of plant species and the ground cover they provide. It is a general term, without specific reference to particular taxa, life forms, structure, spatial extent, or any other specific botanical or geographic charac ...

and rainfall make the Great Desert the hottest large region in the world, and the hottest place on Earth during summer in some spots. The average high temperature exceeds during the hottest month nearly everywhere in the desert except at very high altitudes. The world's highest officially recorded average daily high temperature was in a remote desert town in the

Algerian Desert The Algerian Desert ( ar, الصحراء الجزائرية) is located in north-central Africa and is part of the Sahara Desert. The desert occupies more than four-fifths of Algerian territory. Its expansion starts from the Saharan Atlas as a ...

called

Bou Bernous Bou Bernous is a village in the commune of Oum El Assel, in Tindouf Province, Algeria ) , image_map = Algeria (centered orthographic projection).svg , map_caption = , image_map2 = , capital ...

, at an elevation of above sea level, and only Death Valley, California rivals it. Other hot spots in Algeria such as Adrar,

Timimoun Timimoun ( ar, ﺗﻴﻤﻴﻤﻮن) is a town and commune, and capital of Timimoun District, in Adrar Province, south-central Algeria. According to the 2008 census it has a population of 33,060, up from 28,595 in 1998, with an annual growth rate ...

, In Salah, Ouallene,

Aoulef Aoulef ( ar, أولف , translit=Awlaf) is a town and commune and capital of Aoulef District, in Adrar Province, south-central Algeria. According to the 2008 census it has a population of 21,723, up from 15,229 in 1998, with an annual growth rate ...

, Reggane with an elevation between above sea level get slightly lower summer average highs, around during the hottest months of the year. Salah, well known in Algeria for its extreme heat, has average high temperatures of , , and in June, July, August and September respectively. There are even hotter spots in the Sahara, but they are located in extremely remote areas, especially in the

Azalai The Azalai (Tamasheq, var. Azalay) is a semi-annual salt caravan route practiced by Tuareg traders in the Sahara desert between Timbuktu and the Taoudenni salt mine in Mali, or the act of traveling with a caravan along that route. The other ...

, lying in northern Mali. The major part of the desert experiences around three to five months when the average high strictly exceeds ; while in the southern central part of the desert, there are up to six or seven months when the average high temperature strictly exceeds . Some examples of this are

Bilma Bilma is an oasis town and commune in north east Niger with, as of the 2012 census, a total population of 4,016 people. It lies protected from the desert dunes under the Kaouar Cliffs and is the largest town along the Kaouar escarpment. It ...

, Niger and Faya-Largeau, Chad. The annual average daily temperature exceeds everywhere and can approach in the hottest regions year-round. However, most of the desert has a value in excess of . Sunset in Sahara

Sand and ground temperatures are even more extreme. During daytime, the sand temperature is extremely high: it can easily reach or more. A sand temperature of 83.5 °C (182.3 °F) has been recorded in

Port Sudan Port Sudan ( ar, بور سودان, Būr Sūdān) is a port city in eastern Sudan, and the capital of the state of Red Sea. , it has 489,725 residents. Located on the Red Sea, Port Sudan is recognized as Sudan's main seaport and the source of 9 ...

. Ground temperatures of have been recorded in the Adrar of Mauritania and a value of 75 °C (167 °F) has been measured in

Borkou Borku (french: Borkou) or Borgu (') is a region of Central Africa, mostly in Northern Chad, forming part of the transitional zone between the arid wastes of the Sahara and the fertile lands of the central Sudan. It is bounded N. by the Tibesti ...

, northern Chad. Due to lack of cloud cover and very low humidity, the desert usually has high diurnal temperature variations between days and nights. However, it is a myth that the nights are especially cold after extremely hot days in the Sahara. On average, nighttime temperatures tend to be cooler than in the daytime. The smallest variations are found along the coastal regions due to high humidity and are often even lower than a difference, while the largest variations are found in inland desert areas where the humidity is the lowest, mainly in the southern Sahara. Still, it is true that winter nights can be cold, as it can drop to the freezing point and even below, especially in high-elevation areas. The frequency of subfreezing winter nights in the Sahara is strongly influenced by the North Atlantic Oscillation (NAO), with warmer winter temperatures during negative NAO events and cooler winters with more frosts when the NAO is positive. This is because the weaker clockwise flow around the eastern side of the subtropical anticyclone during negative NAO winters, although too dry to produce more than negligible precipitation, does reduce the flow of dry, cold air from higher latitudes of Eurasia into the Sahara significantly.

Precipitation

The average annual rainfall ranges from very low in the northern and southern fringes of the desert to nearly non-existent over the central and the eastern part. The thin northern fringe of the desert receives more winter cloudiness and rainfall due to the arrival of low pressure systems over the Mediterranean Sea along the polar front, although very attenuated by the rain shadow effects of the mountains and the annual average rainfall ranges from to . For example,

Biskra Biskra ( ar, بسكرة ; ; Latin Vescera) is the capital city of Biskra Province, Algeria. In 2007, its population was recorded as 307,987. Biskra is located in northeastern Algeria, about 248 miles (400 km) from Algiers, 71 miles (115&n ...

, Algeria, and

Ouarzazate Ouarzazate (; ar, ورزازات, Warzāzāt, ; ary, وارزازات, Wārzāzāt; shi, label= Berber, ⵡⴰⵔⵣⴰⵣⴰⵜ, Warzazat), nicknamed ''the door of the desert'', is a city and capital of Ouarzazate Province in the region of D ...

, Morocco, are found in this zone. The southern fringe of the desert along the border with the Sahel receives summer cloudiness and rainfall due to the arrival of the Intertropical Convergence Zone from the south and the annual average rainfall ranges from to . For example, Timbuktu, Mali and Agadez, Niger are found in this zone. The vast central hyper-arid core of the desert is virtually never affected by northerly or southerly atmospheric disturbances and permanently remains under the influence of the strongest anticyclonic weather regime, and the annual average rainfall can drop to less than . In fact, most of the Sahara receives less than . Of the of desert land in the Sahara, an area of about (about 31% of the total area) receives an annual average rainfall amount of or less, while some (about 17% of the total area) receives an average of or less. The annual average rainfall is virtually zero over a wide area of some in the eastern Sahara comprising deserts of: Libya, Egypt and Sudan ( Tazirbu,

Kufra Kufra () is a basinBertarelli (1929), p. 514. and oasis group in the Kufra District of southeastern Cyrenaica in Libya. At the end of nineteenth century Kufra became the centre and holy place of the Senussi order. It also played a minor role ...

, Dakhla,

Kharga The Kharga Oasis (Arabic: , ) ; Coptic: ( "Oasis of Hib", "Oasis of Psoi") is the southernmost of Egypt's five western oases. It is located in the Western Desert, about 200 km (125 miles) to the west of the Nile valley. "Kharga" or " ...

Farafra The Farafra depression ( ar, واحة الفرافرة, ) is a geological depression, the second biggest by size in Western Egypt and the smallest by population, near latitude 27.06° north and longitude 27.97° east. It is in the large Wester ...

, Siwa, Asyut,

Sohag Sohag ( , ), also spelled as ''Sawhāj'', ''Suhag'' and ''Suhaj'', is a city on the west bank of the Nile in Egypt. It has been the capital of Sohag Governorate since 1960, before which the capital was Girga and the name of the governorate was ...

, Luxor, Aswan,

Abu Simbel Abu Simbel is a historic site comprising two massive rock-cut temples in the village of Abu Simbel ( ar, أبو سمبل), Aswan Governorate, Upper Egypt, near the border with Sudan. It is situated on the western bank of Lake Nasser, about ...

, Wadi Halfa) where the long-term mean approximates per year. Rainfall is very unreliable and erratic in the Sahara as it may vary considerably year by year. In full contrast to the negligible annual rainfall amounts, the annual rates of potential evaporation are extraordinarily high, roughly ranging from per year to more than per year in the whole desert. Nowhere else on Earth has air been found as dry and evaporative as in the Sahara region. However, at least two instances of snowfall have been recorded in Sahara, in February 1979 and December 2016, both in the town of Ain Sefra.

Desertification and prehistoric climate

One theory for the formation of the Sahara is that the monsoon in Northern Africa was weakened because of glaciation during the Quaternary period, starting two or three million years ago. Another theory is that the monsoon was weakened when the ancient Tethys Sea dried up during the Tortonian period around 7 million years. The climate of the Sahara has undergone enormous variations between wet and dry over the last few hundred thousand years, believed to be caused by long-term changes in the

North African climate cycle North African climate cycles have a unique history that can be traced back millions of years. The cyclic climate pattern of the Sahara is characterized by significant shifts in the strength of the North African Monsoon. When the North African Monsoo ...

that alters the path of the North African Monsoon – usually southward. The cycle is caused by a 41,000-year cycle in which the tilt of the earth changes between 22° and 24.5°. At present (2000), we are in a dry period, but it is expected that the Sahara will become green again in 15,000 years. When the North African monsoon is at its strongest annual precipitation and subsequent vegetation in the Sahara region increase, resulting in conditions commonly referred to as the " green Sahara". For a relatively weak North African monsoon, the opposite is true, with decreased annual precipitation and less vegetation resulting in a phase of the Sahara climate cycle known as the "desert Sahara". The idea that changes in insolation (solar heating) caused by long-term changes in Earth's orbit are a controlling factor for the long-term variations in the strength of monsoon patterns across the globe was first suggested by Rudolf Spitaler in the late nineteenth century, The hypothesis was later formally proposed and tested by the meteorologist John Kutzbach in 1981. Kutzbach's ideas about the impacts of insolation on global monsoonal patterns have become widely accepted today as the underlying driver of long-term monsoonal cycles. Kutzbach never formally named his hypothesis and as such it is referred to here as the " Orbital Monsoon Hypothesis" as suggested by Ruddiman in 2001. Village Telly in Mali

During the last glacial period, the Sahara was much larger than it is today, extending south beyond its current boundaries. The end of the glacial period brought more rain to the Sahara, from about 8000 BCE to 6000 BCE, perhaps because of low pressure areas over the collapsing ice sheets to the north. Once the ice sheets were gone, the northern Sahara dried out. In the southern Sahara, the drying trend was initially counteracted by the

monsoon A monsoon () is traditionally a seasonal reversing wind accompanied by corresponding changes in precipitation but is now used to describe seasonal changes in atmospheric circulation and precipitation associated with annual latitudinal oscil ...

, which brought rain further north than it does today. By around 4200 BCE, however, the monsoon retreated south to approximately where it is today,Sahara's Abrupt Desertification Started by Changes in Earth's Orbit
Accelerated by Atmospheric and Vegetation Feedbacks. leading to the gradual desertification of the Sahara. The Sahara is now as dry as it was about 13,000 years ago. Lake Chad is the remnant of a former inland sea, paleolake Mega-Chad, which existed during the African humid period. At its largest extent, sometime before 5000 BCE, Lake Mega-Chad was the largest of four Saharan paleolakes, and is estimated to have covered an area of 350,000 km². The Sahara pump theory describes this cycle. During periods of a wet or " Green Sahara", the Sahara becomes a

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 ...

grassland and various flora and fauna become more common. Following inter-pluvial arid periods, the Sahara area then reverts to desert conditions and the flora and fauna are forced to retreat northwards to the Atlas Mountains, southwards into

West Africa West Africa or Western Africa is the westernmost region of Africa. The United Nations defines Western Africa as the 16 countries of Benin, Burkina Faso, Cape Verde, The Gambia, Ghana, Guinea, Guinea-Bissau, Ivory Coast, Liberia, Mali ...

, or eastwards into the Nile Valley. This separates

population Population typically refers to the number of people in a single area, whether it be a city or town, region, country, continent, or the world. Governments typically quantify the size of the resident population within their jurisdiction usi ...

s of some of the species in areas with different

climate Climate is the long-term weather pattern in an area, typically averaged over 30 years. More rigorously, it is the mean and variability of meteorological variables over a time spanning from months to millions of years. Some of the meteorologi ...

s, forcing them to adapt, possibly giving rise to

allopatric speciation Allopatric speciation () – also referred to as geographic speciation, vicariant speciation, or its earlier name the dumbbell model – is a mode of speciation that occurs when biological populations become geographically isolated from ...

It is also proposed that humans accelerated the drying-out period from 6000 to 2500 BCE by pastoralists overgrazing available grassland.

Evidence for cycles

The growth of

speleothems A speleothem (; ) is a geological formation by mineral deposits that accumulate over time in natural caves. Speleothems most commonly form in calcareous caves due to carbonate dissolution reactions. They can take a variety of forms, depending o ...

(which requires rainwater) was detected in Hol-Zakh, Ashalim, Even-Sid, Ma'ale-ha-Meyshar, Ktora Cracks, Nagev Tzavoa Cave, and elsewhere, and has allowed tracking of prehistoric rainfall. The Red Sea coastal route was extremely arid before 140 and after 115 kya (thousands of years ago). Slightly wetter conditions appear at 90–87 kya, but it still was just one tenth the rainfall around 125 kya. In the southern Negev Desert speleothems did not grow between 185 and 140 kya (

MIS MIS or mis may refer to: Science and technology * Management information system * Marine isotope stage, stages of the Earth's climate * Maximal independent set, in graph theory * Metal-insulator-semiconductor, e.g., in MIS capacitor * Minimally i ...

6), 110–90 (MIS 5.4–5.2), nor after 85 kya nor during most of the interglacial period (MIS 5.1), the glacial period and

Holocene The Holocene ( ) is the current geological epoch. It began approximately 11,650 cal years Before Present (), after the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene togeth ...

. This suggests that the southern Negev was arid-to-hyper-arid in these periods. During the

Last Glacial Maximum The Last Glacial Maximum (LGM), also referred to as the Late Glacial Maximum, was the most recent time during the Last Glacial Period that ice sheets were at their greatest extent. Ice sheets covered much of Northern North America, Northern Eu ...

(LGM) the Sahara desert was more extensive than it is now with the extent of the tropical forests being greatly reduced, and the lower temperatures reduced the strength of the Hadley Cell. This is a climate cell which causes rising tropical air of the

Inter-Tropical Convergence Zone The Intertropical Convergence Zone (ITCZ ), known by sailors as the doldrums or the calms because of its monotonous windless weather, is the area where the northeast and the southeast trade winds converge. It encircles Earth near the thermal e ...

(ITCZ) to bring rain to the tropics, while dry descending air, at about 20 degrees north, flows back to the equator and brings desert conditions to this region. It is associated with high rates of wind-blown mineral dust, and these dust levels are found as expected in marine cores from the north tropical Atlantic. But around 12,500 BCE the amount of dust in the cores in the Bølling/ Allerød phase suddenly plummets and shows a period of much wetter conditions in the Sahara, indicating a Dansgaard-Oeschger (DO) event (a sudden warming followed by a slower cooling of the climate). The moister Saharan conditions had begun about 12,500 BCE, with the extension of the ITCZ northward in the northern hemisphere summer, bringing moist wet conditions and a savanna climate to the Sahara, which (apart from a short dry spell associated with the Younger Dryas) peaked during the

Holocene thermal maximum The Holocene Climate Optimum (HCO) was a warm period that occurred in the interval roughly 9,000 to 5,000 years ago BP, with a thermal maximum around 8000 years BP. It has also been known by many other names, such as Altithermal, Climatic Optimu ...

climatic phase at 4000 BCE when mid-latitude temperatures seem to have been between 2 and 3 degrees warmer than in the recent past. Analysis of

Nile River The Nile, , Bohairic , lg, Kiira , 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 the longest riv ...

deposited sediments in the delta also shows this period had a higher proportion of sediments coming from the Blue Nile, suggesting higher rainfall also in the Ethiopian Highlands. This was caused principally by a stronger

al circulation throughout the sub-tropical regions, affecting India, Arabia and the Sahara.

Lake Victoria Lake Victoria is one of the African Great Lakes. With a surface area of approximately , Lake Victoria is Africa's largest lake by area, the world's largest tropical lake, and the world's second-largest fresh water lake by surface area after ...

only recently became the source of the White Nile and dried out almost completely around 15 kya. The sudden subsequent movement of the ITCZ southwards with a

Heinrich event A Heinrich event is a natural phenomenon in which large groups of icebergs break off from glaciers and traverse the North Atlantic. First described by marine geologist Hartmut Heinrich (Heinrich, H., 1988), they occurred during five of the last s ...

(a sudden cooling followed by a slower warming), linked to changes with the

El Niño-Southern Oscillation EL, El or el may refer to: Religion * El (deity), a Semitic word for "God" People * EL (rapper) (born 1983), stage name of Elorm Adablah, a Ghanaian rapper and sound engineer * El DeBarge, music artist * El Franco Lee (1949–2016), American ...

cycle, led to a rapid drying out of the Saharan and Arabian regions, which quickly became desert. This is linked to a marked decline in the scale of the Nile floods between 2700 and 2100 BCE.

Ecoregions

The Sahara comprises several distinct

ecoregion An ecoregion (ecological region) or ecozone (ecological zone) is an ecologically and geographically defined area that is smaller than a bioregion, which in turn is smaller than a biogeographic realm. Ecoregions cover relatively large areas of ...

s. With their variations in temperature, rainfall, elevation, and soil, these regions harbor distinct communities of plants and animals. * The Atlantic coastal desert is a narrow strip along the Atlantic coast where fog generated offshore by the cool Canary Current provides sufficient moisture to sustain a variety of lichens, succulents, and shrubs. It covers an area of in the south of Morocco and Mauritania. * The

North Saharan steppe and woodlands The North Saharan steppe and woodlands is a desert ecoregion, in the deserts and xeric shrublands biome, that forms the northern edge of the Sahara. It extends east and west across Northern Africa, south of the Mediterranean dry woodlands and st ...

is along the northern desert, next to the

Mediterranean forests, woodlands, and scrub Mediterranean forests, woodlands, and scrub is a biome defined by the World Wide Fund for Nature. The biome is generally characterized by dry summers and rainy winters, although in some areas rainfall may be uniform. Summers are typically hot in ...

ecoregions of the northern Maghreb and Cyrenaica. Winter rains sustain shrublands and dry woodlands that form a transition between the Mediterranean climate regions to the north and the hyper-arid Sahara proper to the south. It covers in Algeria, Egypt, Libya, Mauritania, Morocco, and Tunisia. * The Sahara Desert ecoregion covers the hyper-arid central portion of the Sahara where rainfall is minimal and sporadic. Vegetation is rare, and this ecoregion consists mostly of sand dunes (''erg, chech, raoui''), stone plateaus (''hamadas''), gravel plains (''reg''), dry valleys (''wadis''), and salt flats. It covers of: Algeria, Chad, Egypt, Libya, Mali, Mauritania, Niger, and Sudan. * The South Saharan steppe and woodlands ecoregion is a narrow band running east and west between the hyper-arid Sahara and the Sahel savannas to the south. Movements of the equatorial Intertropical Convergence Zone (ITCZ) bring summer rains during July and August which average but vary greatly from year to year. These rains sustain summer pastures of grasses and herbs, with dry woodlands and shrublands along seasonal watercourses. This ecoregion covers in Algeria, Chad, Mali, Mauritania, and Sudan. * In the West Saharan montane xeric woodlands, several volcanic highlands provide a cooler, moister environment that supports Saharo-Mediterranean woodlands and shrublands. The ecoregion covers , mostly in the

Tassili n'Ajjer Tassili n'Ajjer ( Berber: ''Tassili n Ajjer'', ar, طاسيلي ناجر; "Plateau of rivers") is a national park in the Sahara desert, located on a vast plateau in southeastern Algeria. Having one of the most important groupings of prehistoric ...

of Algeria, with smaller enclaves in the Aïr of Niger, the Adrar Plateau of Mauritania, and the Adrar des Iforas of Mali and Algeria. * The Tibesti-Jebel Uweinat montane xeric woodlands ecoregion consists of the Tibesti and

Jebel Uweinat Mount Uwaynat or Gabal El Uweinat ( ar, جبل العوينات ', Arabic for 'Mountain of the springs') is a mountain range in the area of the Egyptian- Libyan- Sudanese tripoint. Because of thousands of prehistoric rock art sites, it is con ...

highlands. Higher and more regular rainfall and cooler temperatures support woodlands and shrublands of date palm,

acacia ''Acacia'', commonly known as the wattles or acacias, is a large genus of shrubs and trees in the subfamily Mimosoideae of the pea family Fabaceae. Initially, it comprised a group of plant species native to Africa and Australasia. The genus nam ...

s, myrtle,

oleander ''Nerium oleander'' ( ), most commonly known as oleander or nerium, is a shrub or small tree cultivated worldwide in temperate and subtropical areas as an ornamental and landscaping plant. It is the only species currently classified in the ge ...

, tamarix, and several rare and endemic plants. The ecoregion covers in the Tibesti of Chad and Libya, and Jebel Uweinat on the border of Egypt, Libya, and Sudan. * The Saharan halophytics is an area of seasonally flooded saline depressions which is home to halophytic (salt-adapted) plant communities. The Saharan halophytics cover including: the Qattara and Siwa depressions in northern Egypt, the

Tunisian salt lakes The Tunisian salt lakes are a series of lakes in central Tunisia, lying south of the Atlas Mountains at the northern edge of the Sahara. The lakes include, from east to west, the Chott el Fedjedj, Chott el Djerid, and Chott el Gharsa. Geograph ...

of central Tunisia,

Chott Melghir Chott Melrhir () also known as Chott Melghir or Chott Melhir is an endorheic chott-kind of salt lake in northeastern Algeria. It is the westernmost part of a series of depressions, which extend from the Gulf of Gabès into the Sahara. They were cr ...

in Algeria, and smaller areas of Algeria, Mauritania, and the southern part of Morocco. * The

is one of the Sahara's most arid regions, with no vegetation and very little life. A barren, flat gravel plain, it extends south of Reggane in Algeria towards the

Adrar des Ifoghas The Adrar des Ifoghas (also Adrar des Iforas; Tamasheq: ⴰⴷⵔⴰⵔ ⵏ ⵉⴼⵓⵖⴰⵙ in Tifinagh; Adrar n Ifoghas; ar, أدرار إيفوغاس Ifoghas' Mountains) is a massif located in the Kidal Region of Mali, reaching into Algeri ...

highlands in northern Mali.

Flora and fauna

The flora of the Sahara is highly diversified based on the bio-geographical characteristics of this vast desert. Floristically, the Sahara has three zones based on the amount of rainfall received – the Northern (Mediterranean), Central and Southern Zones. There are two transitional zones – the Mediterranean-Sahara transition and the Sahel transition zone. The Saharan flora comprises around 2800 species of vascular plants. Approximately a quarter of these are

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

. About half of these species are common to the flora of the Arabian deserts. GueltaCamels

The central Sahara is estimated to include five hundred species of plants, which is extremely low considering the huge extent of the area. Plants such as acacia trees, palms, succulents, spiny shrubs, and grasses have adapted to the arid conditions, by growing lower to avoid water loss by strong winds, by storing water in their thick stems to use it in dry periods, by having long roots that travel horizontally to reach the maximum area of water and to find any surface moisture, and by having small thick leaves or needles to prevent water loss by

evapotranspiration Evapotranspiration (ET) is the combined processes by which water moves from the earth’s surface into the atmosphere. It covers both water evaporation (movement of water to the air directly from soil, canopies, and water bodies) and transp ...

. Plant leaves may dry out totally and then recover. Several species of fox live in the Sahara including: the fennec fox, pale fox and Rüppell's fox. The

addax The addax (''Addax nasomaculatus''), also known as the white antelope and the screwhorn antelope, is an antelope native to the Sahara Desert. The only member of the genus ''Addax'', it was first described scientifically by Henri de Blainvil ...

, a large white antelope, can go nearly a year in the desert without drinking. The dorcas gazelle is a north African gazelle that can also go for a long time without water. Other notable gazelles include the rhim gazelle and dama gazelle. The Saharan cheetah ( northwest African cheetah) lives in Algeria,

Togo Togo (), officially the Togolese Republic (french: République togolaise), is a country in West Africa. It is bordered by Ghana to the west, Benin to the east and Burkina Faso to the north. It extends south to the Gulf of Guinea, where its c ...

, Niger, Mali,

Benin Benin ( , ; french: Bénin , ff, Benen), officially the Republic of Benin (french: République du Bénin), and formerly Dahomey, is a country in West Africa. It is bordered by Togo to the west, Nigeria to the east, Burkina Faso to the nort ...

, and

Burkina Faso Burkina Faso (, ; , ff, 𞤄𞤵𞤪𞤳𞤭𞤲𞤢 𞤊𞤢𞤧𞤮, italic=no) is a landlocked country in West Africa with an area of , bordered by Mali to the northwest, Niger to the northeast, Benin to the southeast, Togo and Ghana t ...

. There remain fewer than 250 mature cheetahs, which are very cautious, fleeing any human presence. The cheetah avoids the sun from April to October, seeking the shelter of shrubs such as

balanites ''Balanites'' is an Afrotropical, Palearctic and Indomalayan genus of flowering plants in the caltrop family, Zygophyllaceae. The name ''Balanites'' derives from the Greek word for an acorn and refers to the fruit, it was coined by Alire Deli ...

and acacias. They are unusually pale. The other cheetah subspecies ( northeast African cheetah) lives in Chad, Sudan and the eastern region of Niger. However, it is currently extinct in the wild in Egypt and Libya. There are approximately 2000 mature individuals left in the wild. Libya 5391 Ubari Lakes Luca Galuzzi 2007

Libya 5391 Ubari Lakes Luca Galuzzi 2007

Other animals include the

monitor lizard Monitor lizards are lizards in the genus ''Varanus,'' the only extant genus in the family Varanidae. They are native to Africa, Asia, and Oceania, and one species is also found in the Americas as an invasive species. About 80 species are rec ...

hyrax Hyraxes (), also called dassies, are small, thickset, herbivorous mammals in the order Hyracoidea. Hyraxes are well-furred, rotund animals with short tails. Typically, they measure between long and weigh between . They are superficially simila ...

, sand vipers, and small populations of African wild dog, in perhaps only 14 countries and red-necked ostrich. Other animals exist in the Sahara (birds in particular) such as African silverbill and black-faced firefinch, among others. There are also small

desert crocodile The West African crocodile, desert crocodile, or sacred crocodile (''Crocodylus suchus'') is a species of crocodile related to – and often confused with – the larger and more aggressive Nile crocodile (''C. niloticus''). Taxonomy Compared ...

s in Mauritania and the

Ennedi Plateau The Ennedi Plateau is located in the northeast of Chad, in the regions of Ennedi-Ouest and Ennedi-Est. It is considered a part of the group of mountains known as the Ennedi Massif found in Chad, which is one of the nine countries that make up ...

of Chad. The deathstalker scorpion can be long. Its venom contains large amounts of agitoxin and scyllatoxin and is very dangerous; however, a sting from this scorpion rarely kills a healthy adult. The

Saharan silver ant The Saharan silver ant (''Cataglyphis bombycina'') is a species of insect that lives in the Sahara Desert. It is the fastest of the world’s 12,000 known ant species, clocking a velocity of 855 millimetres per second (over ). It can travel a le ...

is unique in that due to the extreme high temperatures of their habitat, and the threat of predators, the ants are active outside their nest for only about ten minutes per day.

Dromedary The dromedary (''Camelus dromedarius'' or ;), also known as the dromedary camel, Arabian camel, or one-humped camel, is a large even-toed ungulate, of the genus '' Camelus'', with one hump on its back. It is the tallest of the three species o ...

camels and

goat The goat or domestic goat (''Capra hircus'') is a domesticated species of goat-antelope typically kept as livestock. It was domesticated from the wild goat (''C. aegagrus'') of Southwest Asia and Eastern Europe. The goat is a member of the a ...

s are the domesticated animals most commonly found in the Sahara. Because of its qualities of endurance and speed, the dromedary is the favourite animal used by

nomad A nomad is a member of a community without fixed habitation who regularly moves to and from the same areas. Such groups include hunter-gatherers, pastoral nomads (owning livestock), tinkers and trader nomads. In the twentieth century, the po ...

s. Human activities are more likely to affect the habitat in areas of permanent water (oases) or where water comes close to the surface. Here, the local pressure on natural resources can be intense. The remaining populations of large mammals have been greatly reduced by hunting for food and recreation. In recent years development projects have started in the deserts of Algeria and Tunisia using irrigated water pumped from underground aquifers. These schemes often lead to soil degradation and salinization. Researchers from Hacettepe University have reported that Saharan soil may have bio-available iron and also some essential macro and micro nutrient elements suitable for use as fertilizer for growing wheat.

History

People lived on the edge of the desert thousands of years ago,Discover Magazine
2006-Oct. since the end of the last glacial period. In the Central Sahara, engraved and painted rock art were created perhaps as early as 10,000 years ago, spanning the

Bubaline Period Bubalus, Bubaline, or Large Wild Fauna rock art is the earliest form of Central Saharan rock art, created in an engraved style, which have been dated between 12,000 BCE and 8000 BCE. The Bubaline Period is followed by the Kel Essuf Period. As th ...

, Kel Essuf Period,

Round Head Period Round Head rock art is the earliest painted, monumental form of Central Saharan rock art, which was largely created from 9500 BP to 7500 BP and ceased being created by 3000 BP. The Round Head Period is preceded by the Kel Essuf Period and foll ...

, Pastoral Period, Caballine Period, and Cameline Period. The Sahara was then a much wetter place than it is today. Over 30,000 petroglyphs of river animals such as

crocodile Crocodiles (family Crocodylidae) or true crocodiles are large semiaquatic reptiles that live throughout the tropics in Africa, Asia, the Americas and Australia. The term crocodile is sometimes used even more loosely to include all extant me ...

sNational Geographic News
17 June 2006. survive, with half found in the Tassili n'Ajjer in southeast Algeria.

Fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

s of

dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is t ...

s, including '' Afrovenator'', ''

Jobaria ''Jobaria'' is a genus of sauropod dinosaur that lived in what is now Niger during the middle Jurassic Period, between 164 and 161 million years ago. ''Jobaria'' is currently the only known valid sauropod from the Tiouraren, where it was disc ...

'' and '' Ouranosaurus'', have also been found here. The modern Sahara, though, is not lush in vegetation, except in the

Nile The Nile, , Bohairic , lg, Kiira , 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 the longest riv ...

Valley, at a few

oases In ecology, an oasis (; ) is a fertile area of a desert or semi-desert environment'ksar''with its surrounding feeding source, the palm grove, within a relational and circulatory nomadic system.” The location of oases has been of critical im ...

, and in the northern highlands, where Mediterranean plants such as the olive tree are found to grow. It was long believed that the region had been this way since about 1600 BCE, after shifts in Earth's axis increased temperatures and decreased precipitation, which led to the abrupt desertification of North Africa about 5,400 years ago.

Kiffians

The

Kiffian culture The Kiffian culture is a prehistoric industry, or domain, that existed between approximately 8,000 BC and 6,000 BC in the Sahara Desert, during the African humid period referred to as the Neolithic Subpluvial. Human remains from this culture were ...

is a prehistoric industry, or domain, that existed between 10,000 and 8,000 years ago in the Sahara, during the Neolithic Subpluvial. Human remains from this culture were found in 2000 at a site known as Gobero, located in

Niger ) , official_languages = , languages_type = National languagesTénéré Desert The Ténéré (Tuareg: Tenere, literally: "desert") is a desert region in the south central Sahara. It comprises a vast plain of sand stretching from northeastern Niger into western Chad, occupying an area of over . The Ténéré's boundaries are ...

. The site is known as the largest and earliest grave of Stone Age people in the Sahara desert. The Kiffians were skilled hunters. Bones of many large savannah animals that were discovered in the same area suggest that they lived on the shores of a lake that was present during the Holocene Wet Phase, a period when the Sahara was verdant and wet. The Kiffian people were tall, standing over six feet in height. Craniometric analysis indicates that this early

population was closely related to the Late Pleistocene

Iberomaurusian The Iberomaurusian is a backed bladelet lithic industry found near the coasts of Morocco, Algeria, and Tunisia. It is also known from a single major site in Libya, the Haua Fteah, where the industry is locally known as the Eastern Oranian.The " ...

s and early Holocene Capsians of the Maghreb, as well as mid-Holocene

Mechta ''Luna 1'', also known as ''Mechta'' (russian: Мечта , '' lit.'': ''Dream''), ''E-1 No.4'' and ''First Lunar Rover'', was the first spacecraft to reach the vicinity of Earth's Moon, and the first spacecraft to be placed in heliocentric or ...

groups. Traces of the Kiffian culture do not exist after 8,000 years ago, as the Sahara went through a dry period for the next thousand years. After this time, the

Tenerian culture The Tenerian culture is a prehistoric industry that existed between the 5th millennium BC and mid-3rd millennium BC in the Sahara Desert. This spans the Neolithic Subpluvial and later desiccation, during the middle Holocene. French archaeologist ...

colonized the area.

Tenerians

Gobero was discovered in 2000 during an archaeological expedition led by

Paul Sereno Paul Callistus Sereno (born October 11, 1957) is a professor of paleontology at the University of Chicago and a National Geographic "explorer-in-residence" who has discovered several new dinosaur species on several continents, including at si ...

, which sought

remains. Two distinct prehistoric cultures were discovered at the site: the early

Kiffian culture, and the middle Holocene

. The post-Kiffian desiccation lasted until around 4600 BCE, when the earliest artefacts associated with the Tenerians have been dated to. Some 200 skeletons have been discovered at Gobero. The Tenerians were considerably shorter in height and less robust than the earlier Kiffians. Craniometric analysis also indicates that they were osteologically distinct. The Kiffian skulls are akin to those of the

Late Pleistocene The Late Pleistocene is an unofficial age in the international geologic timescale in chronostratigraphy, also known as Upper Pleistocene from a stratigraphic perspective. It is intended to be the fourth division of the Pleistocene Epoch withi ...

s, early Holocene Capsians, and mid-Holocene

groups, whereas the Tenerian crania are more like those of Mediterranean groups. Graves show that the Tenerians observed spiritual traditions, as they were buried with artifacts such as jewelry made of hippo tusks and clay pots. The most interesting find is a triple burial, dated to 5300 years ago, of an adult female and two children, estimated through their teeth as being five and eight years old, hugging each other. Pollen residue indicates they were buried on a bed of flowers. The three are assumed to have died within 24 hours of each other, but as their skeletons hold no apparent trauma (they did not die violently) and they have been buried so elaborately – unlikely if they had died of a plague – the cause of their deaths is a mystery. Vue de Taghit

Tashwinat Mummy

Uan Muhuggiag appears to have been inhabited from at least the 6th millennium BCE to about 2700 BCE, although not necessarily continuously. The most noteworthy find at Uan Muhuggiag is the well-preserved mummy of a young boy of approximately years old. The child was in a fetal position, then embalmed, then placed in a sack made of antelope skin, which was insulated by a layer of leaves. The boy's organs were removed, as evidenced by incisions in his stomach and thorax, and an organic preservative was inserted to stop his body from decomposing. An ostrich eggshell necklace was also found around his neck.

Radiocarbon dating Radiocarbon dating (also referred to as carbon dating or carbon-14 dating) is a method for determining the age of an object containing organic material by using the properties of radiocarbon, a radioactive isotope of carbon. The method was de ...

determined the age of the mummy to be approximately 5600 years old, which makes it about 1000 years older than the earliest previously recorded mummy in ancient

. In 1958–59, an archaeological expedition led by

Antonio Ascenzi Antonio is a masculine given name of Etruscan origin deriving from the root name Antonius. It is a common name among Romance language-speaking populations as well as the Balkans and Lusophone Africa. It has been among the top 400 most popular m ...

conducted anthropological, radiological, histological and chemical analyses on the Uan Muhuggiag mummy. The team claimed that the mummy was a 30-month-old child of uncertain sex who possessed Negroid features (Note: "negroid" is derived from a disproven theory of biological race, and modern genetics has since rendered such terminology obsolete). A long incision on the specimen's abdominal wall also indicated that the body had been initially mummified by evisceration and later underwent natural desiccation. One other individual, an adult, was found at Uan Muhuggiag, buried in a crouched position. However, the body showed no evidence of evisceration or any other method of preservation. The body was estimated to date from about 7500 BP.

Nubians

During the

Neolithic The Neolithic period, or New Stone Age, is an Old World archaeological period and the final division of the Stone Age. It saw the Neolithic Revolution, a wide-ranging set of developments that appear to have arisen independently in several pa ...

Era, before the onset of desertification around 9500 BCE, the central Sudan had been a rich environment supporting a large population ranging across what is now barren desert, like the Wadi el-Qa'ab. By the 5th millennium BCE, the people who inhabited what is now called

Nubia Nubia () ( Nobiin: Nobīn, ) is a region along the Nile river encompassing the area between the first cataract of the Nile (just south of Aswan in southern Egypt) and the confluence of the Blue and White Niles (in Khartoum in central Sud ...

were full participants in the "agricultural revolution", living a settled lifestyle with domesticated plants and animals. Saharan rock art of cattle and herdsmen suggests the presence of a cattle cult like those found in Sudan and other pastoral societies in Africa today.

Megalith A megalith is a large stone that has been used to construct a prehistoric structure or monument, either alone or together with other stones. There are over 35,000 in Europe alone, located widely from Sweden to the Mediterranean sea. The ...

s found at Nabta Playa are overt examples of probably the world's first known

archaeoastronomy Archaeoastronomy (also spelled archeoastronomy) is the interdisciplinary or multidisciplinary study of how people in the past "have understood the phenomena in the sky, how they used these phenomena and what role the sky played in their cu ...

devices, predating

Stonehenge Stonehenge is a prehistoric monument on Salisbury Plain in Wiltshire, England, west of Amesbury. It consists of an outer ring of vertical sarsen standing stones, each around high, wide, and weighing around 25 tons, topped by connec ...

by some 2,000 years. This complexity, as observed at Nabta Playa, and as expressed by different levels of authority within the society there, likely formed the basis for the structure of both the Neolithic society at Nabta and the Old Kingdom of Egypt. Archaeological evidence has attested that population settlements occurred in Nubia as early as the Late

Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fina ...

era and from the 5th millennium BC onwards, whereas there is "no or scanty evidence" of human presence in the Egyptian Nile Valley during these periods, which may be due to problems in site preservation.

Egyptians

By 6000 BCE

predynastic Egypt Prehistoric Egypt and Predynastic Egypt span the period from the earliest human settlement to the beginning of the Early Dynastic Period around 3100 BC, starting with the first Pharaoh, Narmer for some Egyptologists, Hor-Aha for others, with ...

ians in the southwestern corner of Egypt were herding cattle and constructing large buildings. Subsistence in organized and permanent settlements in predynastic Egypt by the middle of the 6th millennium BCE centered predominantly on cereal and animal agriculture: cattle, goats, pigs and sheep. Metal objects replaced prior ones of stone. Tanning of animal skins, pottery and weaving were commonplace in this era also. There are indications of seasonal or only temporary occupation of the

Al Fayyum Faiyum ( ar, الفيوم ' , borrowed from cop, ̀Ⲫⲓⲟⲙ or Ⲫⲓⲱⲙ ' from egy, pꜣ ym "the Sea, Lake") is a city in Middle Egypt. Located southwest of Cairo, in the Faiyum Oasis, it is the capital of the modern Faiy ...

in the 6th millennium BCE, with food activities centering on fishing, hunting and food-gathering. Stone arrowheads, knives and scrapers from the era are commonly found.Fayum, Qarunian
(Fayum B, about 6000–5000 BCE?)
Digital Egypt
Burial items included pottery, jewelry, farming and hunting equipment, and assorted foods including dried meat and fruit. Burial in desert environments appears to enhance Egyptian preservation rites, and the dead were buried facing due west.Predynastic (5,500–3,100 BCE), Tour Egypt. Several scholars have argued that the African origins of the Egyptian civilisation derived from pastoral communities which emerged in both the Egyptian and Sudanese regions of the Nile Valley in the fifth millennium BCE. By 3400 BCE, the Sahara was as dry as it is today, due to reduced precipitation and higher temperatures resulting from a shift in Earth's orbit. As a result of this aridification, it became a largely impenetrable barrier to humans, with the remaining settlements mainly being concentrated around the numerous oases that dot the landscape. Little trade or commerce is known to have passed through the interior in subsequent periods, the only major exception being the Nile Valley. The Nile, however, was impassable at several

cataracts A cataract is a cloudy area in the lens of the eye that leads to a decrease in vision. Cataracts often develop slowly and can affect one or both eyes. Symptoms may include faded colors, blurry or double vision, halos around light, trouble ...

, making trade and contact by boat difficult.

Tichitt culture

In 4000 BCE, the start of sophisticated social structure (e.g., trade of cattle as valued assets) developed among herders amid the Pastoral Period of the Sahara. Saharan pastoral culture (e.g., fields of tumuli, lustrous stone rings, axes) was intricate. By 1800 BCE, Saharan pastoral culture expanded throughout the Saharan and Sahelian regions. The initial stages of sophisticated social structure among Saharan herders served as the segue for the development of sophisticated hierarchies found in African settlements, such as

Dhar Tichitt Dhar Tichitt is a Neolithic archaeological site located in the southwestern region of the Sahara Desert, in Mauritania. It is one of several settlement locations along the sandstone cliffs in the area. Dhar Tichitt, Dhar Walata, Dhar Néma, and ...

. After migrating from the Central Sahara, Mande peoples established their civilization in the Tichitt region of the Western Sahara The Tichitt Tradition of eastern Mauritania dates from 2200 BCE to 200 BCE. Tichitt culture, at Dhar Néma, Dhar Tagant, Dhar Tichitt, and Dhar Walata, included a four-tiered hierarchal social structure,

farming Agriculture or farming is the practice of cultivating plants and livestock. Agriculture was the key development in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that enabled peopl ...

cereals A cereal is any grass cultivated for the edible components of its grain (botanically, a type of fruit called a caryopsis), composed of the endosperm, germ, and bran. Cereal grain crops are grown in greater quantities and provide more food ...

, metallurgy, numerous

funerary A funeral is a ceremony connected with the final disposition of a corpse, such as a burial or cremation, with the attendant observances. Funerary customs comprise the complex of beliefs and practices used by a culture to remember and respect ...

tombs, and a rock art tradition At Dhar Tichitt and Dhar Walata, pearl millet may have also been independently tamed amid the

. The urban Tichitt Tradition may have been the earliest large-scale, complexly organized society in

, and an early

civilization A civilization (or civilisation) is any complex society characterized by the development of a state, social stratification, urbanization, and symbolic systems of communication beyond natural spoken language (namely, a writing system). ...

of the Sahara, which may have served as the segue for state formation in West Africa. As areas where the Tichitt cultural tradition were present, Dhar Tichitt and Dhar Walata were occupied more frequently than Dhar Néma. Farming of crops (e.g., millet) may have been a feature of the Tichitt cultural tradition as early as 3rd millennium BCE in Dhar Tichitt. As part of a broader trend of iron metallurgy developed in the West African Sahel amid 1st millennium BCE, iron items (350 BCE – 100 CE) were found at Dhar Tagant, iron metalworking and/or items (800 BCE – 400 BCE) were found at Dia Shoma and Walaldé, and the iron remnants (760 BCE – 400 BCE) found at Bou Khzama and Djiganyai. The iron materials that were found are evidence of iron metalworking at Dhar Tagant. In the late period of the Tichitt Tradition at Dhar Néma, tamed pearl millet was used to temper the tuyeres of a oval-shaped low shaft furnace; this furnace was one out of 16 iron furnaces located on elevated ground.

Iron metallurgy Ferrous metallurgy is the metallurgy of iron and its alloys. The earliest surviving prehistoric iron artifacts, from the 4th millennium BC in Egypt, were made from meteoritic iron-nickel. It is not known when or where the smelting of iron from ...

may have developed before the second half of 1st millennium BCE, as indicated by pottery dated between 800 BCE and 200 BCE. At Dhar Walata and Dhar Tichitt,

copper Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pink ...

was also used. After its decline in Mauritania, the Tichitt Tradition spread to the Middle Niger region (e.g., Méma, Macina, Dia Shoma,

Jenne Jeno Jenne can refer to: * Djenné, a city of Mali * Jenne, Lazio, a city and comune in the Metropolitan City of Rome, Italy People with the given name * Jenne Langhout (1918–2010), Dutch field hockey player * Jenne Lennon (), American singer People ...

) of Mali where it developed into and persisted as Faïta Facies ceramics between 1300 BCE and 400 BCE among rammed earth architecture and iron metallurgy (which had developed after 900 BCE). Thereafter, the

Ghana Empire The Ghana Empire, also known as Wagadou ( ar, غانا) or Awkar, was a West African empire based in the modern-day southeast of Mauritania and western Mali that existed from c. 300 until 1100. The Empire was founded by the Soninke people, a ...

developed in the 1st millennium CE.

Phoenicians

The people of

Phoenicia Phoenicia () was an ancient thalassocratic civilization originating in the Levant region of the eastern Mediterranean, primarily located in modern Lebanon. The territory of the Phoenician city-states extended and shrank throughout their his ...

, who flourished from 1200 to 800 BCE, created a chain of settlements along the coast of North Africa and traded extensively with its inhabitants. This put them in contact with the people of ancient Libya, who were the ancestors of people who speak

Berber languages The Berber languages, also known as the Amazigh languages or Tamazight,, ber, label=Tuareg Tifinagh, ⵜⵎⵣⵗⵜ, ) are a branch of the Afroasiatic language family. They comprise a group of closely related languages spoken by Berber commun ...

in North Africa and the Sahara today. The Libyco-Berber alphabet of the ancient Libyans of north Africa seems to have been based on Phoenician, and its descendant Tifinagh is still used today by the (Berber)

Tuareg The Tuareg people (; also spelled Twareg or Touareg; endonym: ''Imuhaɣ/Imušaɣ/Imašeɣăn/Imajeɣăn'') are a large Berber ethnic group that principally inhabit the Sahara in a vast area stretching from far southwestern Libya to southern Al ...

of the central Sahara. The Periplus of the Phoenician navigator Hanno, who lived sometime in the 5th century BC, claims that he founded settlements along the Atlantic coast of Africa, possibly including the Western Sahara. The identification of the places discussed is controversial, and archeological confirmation is lacking.

Greeks

By 500 BCE,

Greeks The Greeks or Hellenes (; el, Έλληνες, ''Éllines'' ) are an ethnic group and nation indigenous to the Eastern Mediterranean and the Black Sea regions, namely Greece, Cyprus, Albania, Italy, Turkey, Egypt, and, to a lesser extent, ot ...

arrived in the desert. Greek traders spread along the eastern coast of the desert, establishing trading colonies along the

. The

Carthaginians The Punic people, or western Phoenicians, were a Semitic people in the Western Mediterranean who migrated from Tyre, Phoenicia to North Africa during the Early Iron Age. In modern scholarship, the term ''Punic'' – the Latin equivalent of the ...

explored the Atlantic coast of the desert, but the turbulence of the waters and the lack of markets caused a lack of presence further south than modern Morocco. Centralized states thus surrounded the desert on the north and east; it remained outside the control of these states. Raids from the nomadic Berber people of the desert were of constant concern to those living on the edge of the desert.

Urban civilization

An urban civilization, the Garamantes, arose around 500 BCE in the heart of the Sahara, in a valley that is now called the Wadi al-Ajal in Fezzan, Libya. The Garamantes achieved this development by digging tunnels far into the mountains flanking the valley to tap fossil water and bring it to their fields. The Garamantes grew populous and strong, conquering their neighbors and capturing many slaves (who were put to work extending the tunnels). The ancient Greeks and the Romans knew of the Garamantes and regarded them as uncivilized nomads. However, they traded with them, and a Roman bath has been found in the Garamantes' capital of Garama. Archaeologists have found eight major towns and many other important settlements in the Garamantes' territory. The Garamantes' civilization eventually collapsed after they had depleted available water in the

aquifer An aquifer is an underground layer of water-bearing, permeable rock, rock fractures, or unconsolidated materials ( gravel, sand, or silt). Groundwater from aquifers can be extracted using a water well. Aquifers vary greatly in their characte ...

s and could no longer sustain the effort to extend the tunnels further into the mountains. Between the first century BCE and the fourth century CE, several Roman expeditions into the Sahara were conducted by groups of military and commercial units of Romans.

Berbers

The

Berber people , image = File:Berber_flag.svg , caption = The Berber ethnic flag , population = 36 million , region1 = Morocco , pop1 = 14 million to 18 million , region2 = Algeria , pop2 ...

occupied (and still occupy with Arabs) much of the Sahara. The Garamantes Berbers built a prosperous empire in the heart of the desert. The Tuareg nomads continue to inhabit and move across wide Sahara surfaces to the present day.

Islamic and Arabic expansion

The

Byzantine Empire The Byzantine Empire, also referred to as the Eastern Roman Empire or Byzantium, was the continuation of the Roman Empire primarily in its eastern provinces during Late Antiquity and the Middle Ages, when its capital city was Constantinopl ...

ruled the northern shores of the Sahara from the 5th to the 7th centuries. After the Muslim conquest of Arabia, specifically the Arabian peninsula, the Muslim conquest of North Africa began in the mid-7th to early 8th centuries and Islamic influence expanded rapidly on the Sahara. By the end of 641 all of Egypt was in Muslim hands. Trade across the desert intensified, and a significant

slave trade Slavery and enslavement are both the state and the condition of being a slave—someone forbidden to quit one's service for an enslaver, and who is treated by the enslaver as property. Slavery typically involves slaves being made to perf ...

crossed the desert. It has been estimated that from the 10th to 19th centuries some 6,000 to 7,000 slaves were transported north each year. The Beni Ḥassān and other nomadic Arab tribes dominated the

Sanhaja The Sanhaja ( ber, Aẓnag, pl. Iẓnagen, and also Aẓnaj, pl. Iẓnajen; ar, صنهاجة, ''Ṣanhaja'' or زناگة ''Znaga'') were once one of the largest Berber tribal confederations, along with the Zanata and Masmuda confederations. Man ...

Berber tribes of the western Sahara after the Char Bouba war of the 17th century. As a result, Arabian culture and language came to dominate, and the Berber tribes underwent some Arabization.

Ottoman Turkish era

In the 16th century the northern fringe of the Sahara, such as coastal regencies in present-day

Algeria ) , image_map = Algeria (centered orthographic projection).svg , map_caption = , image_map2 = , capital = Algiers , coordinates = , largest_city = capital , relig ...

and Tunisia, as well as some parts of present-day Libya, together with the semi-autonomous kingdom of Egypt, were occupied by the

Ottoman Empire The Ottoman Empire, * ; is an archaic version. The definite article forms and were synonymous * and el, Оθωμανική Αυτοκρατορία, Othōmanikē Avtokratoria, label=none * info page on book at Martin Luther University ...

. From 1517 Egypt was a valued part of the Ottoman Empire, ownership of which provided the Ottomans with control over the Nile Valley, the east Mediterranean and North Africa. The benefit of the Ottoman Empire was the freedom of movement for citizens and goods. Traders exploited the Ottoman land routes to handle the spices, gold and silk from the East, manufactured goods from Europe, and the slave and gold traffic from Africa. Arabic continued as the local language and Islamic culture was much reinforced. The Sahel and southern Sahara regions were home to several independent states or to roaming Tuareg clans.

European colonialism

European colonialism in the Sahara began in the 19th century.

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of Overseas France, overseas regions and territories in the Americas and the Atlantic Ocean, Atlantic, Pacific Ocean, Pac ...

conquered the regency of Algiers from the Ottomans in 1830, and French rule spread south from

French Algeria French Algeria (french: Alger to 1839, then afterwards; unofficially , ar, الجزائر المستعمرة), also known as Colonial Algeria, was the period of French colonisation of Algeria. French rule in the region began in 1830 with the ...

and eastwards from

Senegal Senegal,; Wolof: ''Senegaal''; Pulaar: 𞤅𞤫𞤲𞤫𞤺𞤢𞥄𞤤𞤭 (Senegaali); Arabic: السنغال ''As-Sinighal'') officially the Republic of Senegal,; Wolof: ''Réewum Senegaal''; Pulaar : 𞤈𞤫𞤲𞤣𞤢𞥄𞤲𞤣𞤭 ...

into the upper

Niger ) , official_languages = , languages_type = National languagesFrench Sudan including

(1893), Mauritania, Morocco (1912), Niger, and Tunisia (1881). By the beginning of the 20th century, the trans-Saharan trade had clearly declined because goods were moved through more modern and efficient means, such as airplanes, rather than across the desert. The French took advantage of long-standing animosity between the

Chaamba The Chaamba ( ar, الشعانبة, translit=Sha‘āniba) are an Arab tribe in the northern Sahara of central Algeria. They are a large tribe of Bedouins and live in a large desert territory to the south of the Atlas Mountains, around Metlili, E ...

Arabs and the Tuareg. The newly raised ''Méhariste'' camel corps were originally recruited mainly from the Chaamba nomadic tribe. In 1902, the French penetrated Hoggar Mountains and defeated Ahaggar Tuareg in the battle of Tit. Scramble-for-Africa-1880-1913

The French Colonial Empire was the dominant presence in the Sahara. It established regular air links from

Toulouse Toulouse ( , ; oc, Tolosa ) is the prefecture of the French department of Haute-Garonne and of the larger region of Occitania. The city is on the banks of the River Garonne, from the Mediterranean Sea, from the Atlantic Ocean and fr ...

(HQ of famed Aéropostale), to

Oran Oran ( ar, وَهران, Wahrān) is a major coastal city located in the north-west of Algeria. It is considered the second most important city of Algeria after the capital Algiers, due to its population and commercial, industrial, and cultural ...

and over the

Hoggar The Hoggar Mountains ( ar, جبال هقار, Berber: ''idurar n Ahaggar'') are a highland region in the central Sahara in southern Algeria, along the Tropic of Cancer. The mountains cover an area of approximately 550,000 km. Geography This ...

to Timbuktu and West to

Bamako Bamako ( bm, ߓߡߊ߬ߞߐ߬ ''Bàmakɔ̌'', ff, 𞤄𞤢𞤥𞤢𞤳𞤮 ''Bamako'') is the capital and largest city of Mali, with a 2009 population of 1,810,366 and an estimated 2022 population of 2.81 million. It is located on the Niger Rive ...

and

Dakar Dakar ( ; ; wo, Ndakaaru) (from daqaar ''tamarind''), is the capital and largest city of Senegal. The city of Dakar proper has a population of 1,030,594, whereas the population of the Dakar metropolitan area is estimated at 3.94 million in 2 ...

, as well as trans-Sahara bus services run by La Compagnie Transsaharienne (est. 1927). A remarkable film shot by famous aviator Captain René Wauthier documents the first crossing by a large truck convoy from Algiers to Tchad, across the Sahara. Egypt, under Muhammad Ali and his successors, conquered Nubia in 1820–22, founded

Khartoum Khartoum or Khartum ( ; ar, الخرطوم, Al-Khurṭūm, din, Kaartuɔ̈m) is the capital of Sudan. With a population of 5,274,321, its metropolitan area is the largest in Sudan. It is located at the confluence of the White Nile, flowing n ...

in 1823, and conquered Darfur in 1874. Egypt, including the Sudan, became a British protectorate in 1882. Egypt and Britain lost control of the Sudan from 1882 to 1898 as a result of the

Mahdist War The Mahdist War ( ar, الثورة المهدية, ath-Thawra al-Mahdiyya; 1881–1899) was a war between the Mahdist Sudanese of the religious leader Muhammad Ahmad bin Abd Allah, who had proclaimed himself the "Mahdi" of Islam (the "Guided On ...

. After its capture by British troops in 1898, the Sudan became an Anglo-Egyptian

condominium A condominium (or condo for short) is an ownership structure whereby a building is divided into several units that are each separately owned, surrounded by common areas that are jointly owned. The term can be applied to the building or complex ...

Spain , image_flag = Bandera de España.svg , image_coat = Escudo de España (mazonado).svg , national_motto = '' Plus ultra'' (Latin)(English: "Further Beyond") , national_anthem = (English: "Royal March") , ...

captured present-day Western Sahara after 1874, although Rio del Oro remained largely under Sahrawi influence. In 1912,

Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical ...

captured parts of what was to be named

from the Ottomans. To promote the

Roman Catholic Roman or Romans most often refers to: * Rome, the capital city of Italy *Ancient Rome, Roman civilization from 8th century BC to 5th century AD * Roman people, the people of ancient Rome *'' Epistle to the Romans'', shortened to ''Romans'', a let ...

religion in the desert,

Pope Pius IX Pope Pius IX ( it, Pio IX, ''Pio Nono''; born Giovanni Maria Mastai Ferretti; 13 May 1792 – 7 February 1878) was head of the Catholic Church from 1846 to 1878, the longest verified papal reign. He was notable for convoking the First Vatican ...

appointed a delegate Apostolic of the Sahara and the Sudan in 1868; later in the 19th century his jurisdiction was reorganized into the

Vicariate Apostolic of Sahara The Vicariate Apostolic of Sahara ( la, Vicariatus Apostolicus Saharensis) is a former Roman Catholic missionary jurisdiction in colonial Algeria and Libya. History The Sahara is a vast desert of northern Africa, measuring about 932 miles from nor ...

Breakup of the empires and afterwards

Libya 5101 Fozzigiaren Arch Tadrart Acacus Luca Galuzzi 2007

Egypt became independent of Britain in 1936, although the Anglo-Egyptian treaty of 1936 allowed Britain to keep troops in Egypt and to maintain the British-Egyptian condominium in the Sudan. British military forces were withdrawn in 1954. Most of the Saharan states achieved independence after

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the World War II by country, vast majority of the world's countries—including all of the great power ...

: Libya in 1951; Morocco, Sudan, and Tunisia in 1956; Chad, Mali, Mauritania, and Niger in 1960; and Algeria in 1962. Spain withdrew from Western Sahara in 1975, and it was partitioned between Mauritania and Morocco. Mauritania withdrew in 1979; Morocco continues to hold the territory (see Western Sahara conflict). Tuareg people in Mali rebelled several times during the 20th century before finally forcing the Malian armed forces to withdraw below the line demarcating

Azawad Azawad, or Azawagh (Tuareg: Azawaɣ, or Azawad; ar, أزواد) was a short-lived unrecognised state from 2012 to 2013. Azawagh (''Azawaɣ'') is the generic Tuareg Berber name of all Tuareg Berber areas, especially the northern half of Mal ...

from southern Mali during the 2012 rebellion. Islamist rebels in the Sahara calling themselves al-Qaeda in the Islamic Maghreb have stepped up their violence in recent years. In the post–World War II era, several mines and communities have developed to use the desert's natural resources. These include large deposits of oil and

natural gas Natural gas (also called fossil gas or simply gas) is a naturally occurring mixture of gaseous hydrocarbons consisting primarily of methane in addition to various smaller amounts of other higher alkanes. Low levels of trace gases like carbon d ...

in Algeria and Libya, and large deposits of

phosphate In chemistry, a phosphate is an anion, salt, functional group or ester derived from a phosphoric acid. It most commonly means orthophosphate, a derivative of orthophosphoric acid . The phosphate or orthophosphate ion is derived from phosph ...

s in Morocco and Western Sahara. Libya's

Great Man-Made River The Great Man-Made River (GMMR, ) is a network of pipes that supplies fresh water obtained from the Nubian Sandstone Aquifer System fossil aquifer across Libya. It is the world's largest irrigation project. The project utilizes a pipeline system ...

is the world's largest irrigation project. The project uses a pipeline system that pumps fossil water from the

Nubian Sandstone Aquifer System The Nubian Sandstone Aquifer System (NSAS) is the world's largest known fossil water aquifer system. It is located underground in the Eastern end of the Sahara desert and spans the political boundaries of four countries in north-eastern Africa. N ...

to cities in the populous Libyan northern Mediterranean coast including Tripoli and Benghazi. A number of Trans-African highways have been proposed across the Sahara, including the Cairo–Dakar Highway along the Atlantic coast, the Trans-Sahara Highway from Algiers on the Mediterranean to Kano in Nigeria, the

Tripoli – Cape Town Highway Tripoli or Tripolis may refer to: Cities and other geographic units Greece *Tripoli, Greece, the capital of Arcadia, Greece * Tripolis (region of Arcadia), a district in ancient Arcadia, Greece * Tripolis (Larisaia), an ancient Greek city in ...

from Tripoli in Libya to N'Djamena in Chad, and the

Cairo – Cape Town Highway Cairo ( ; ar, القاهرة, al-Qāhirah, ) is the capital of Egypt and its largest city, home to 10 million people. It is also part of the largest urban agglomeration in Africa, the Arab world and the Middle East: The Greater Cairo metro ...

which follows the Nile. Each of these highways is partially complete, with significant gaps and unpaved sections.

People, culture, and languages

The people of the Sahara are of various origins. Among them the Amazigh including the

, various

Arabized Arabization or Arabisation ( ar, تعريب, ') describes both the process of growing Arab influence on non-Arab populations, causing a language shift by the latter's gradual adoption of the Arabic language and incorporation of Arab culture, ...

Amaziɣ groups such as the Hassaniya-speaking Sahrawis, whose populations include the Znaga, a tribe whose name is a remnant of the pre-historic

Zenaga language Zenaga (autonym: ' or ') is a Berber language on the verge of extinction currently spoken in Mauritania and northern Senegal by a few hundred people. Zenaga Berber is spoken as a mother tongue from the town of Mederdra in southwestern Maurita ...

. Other major groups of people include the: Toubou, Nubians,

Zaghawa Zaghawa may refer to: * Zaghawa people * Zaghawa language Zaghawa is a Saharan language spoken by the Zaghawa people of east-central Chad (in the Sahel) and northwestern Sudan (Darfur). The people who speak this language call it Beria, from ''B ...

, Kanuri, Hausa, Songhai, Beja, and Fula/Fulani (french: Peul; ff, Fulɓe). The archaeological evidence from the Holocene period has shown that

Nilo-Saharan The Nilo-Saharan languages are a proposed family of African languages spoken by some 50–60 million people, mainly in the upper parts of the Chari and Nile rivers, including historic Nubia, north of where the two tributaries of the Nile meet. ...

speaking groups had populated the central and southern Sahara before the influx of Berber and

Arabic Arabic (, ' ; , ' or ) is a Semitic language spoken primarily across the Arab world.Semitic languages: an international handbook / edited by Stefan Weninger; in collaboration with Geoffrey Khan, Michael P. Streck, Janet C. E.Watson; Walter ...

speakers, around 1500 years ago, who now largely populate the Sahara in the modern era. Arabic dialects are the most widely spoken languages in the Sahara. Arabic, Berber and its variants now regrouped under the term Amazigh (which includes the

Guanche language Guanche is an extinct language that was spoken by the Guanches of the Canary Islands until the 16th or 17th century. It died out after the conquest of the Canary Islands as the Guanche ethnic group was assimilated into the dominant Spanish cul ...

spoken by the original Berber inhabitants of the Canary Islands) and Beja languages are part of the

Afro-Asiatic The Afroasiatic languages (or Afro-Asiatic), also known as Hamito-Semitic, or Semito-Hamitic, and sometimes also as Afrasian, Erythraean or Lisramic, are a language family of about 300 languages that are spoken predominantly in the geographic s ...

Hamito-Semitic The Afroasiatic languages (or Afro-Asiatic), also known as Hamito-Semitic, or Semito-Hamitic, and sometimes also as Afrasian, Erythraean or Lisramic, are a language family of about 300 languages that are spoken predominantly in the geographic s ...

family. Unlike neighboring

and the central governments of the states that comprise the Sahara, the French language bears little relevance to inter-personal discourse and commerce within the region, its people retaining staunch ethnic and political affiliations with

and Berber leaders and culture. The legacy of the French colonial era administration is primarily manifested in the territorial reorganization enacted by the

Third Third or 3rd may refer to: Numbers * 3rd, the ordinal form of the cardinal number 3 * , a fraction of one third * 1⁄60 of a ''second'', or 1⁄3600 of a ''minute'' Places * 3rd Street (disambiguation) * Third Avenue (disambiguation) * Hi ...

and Fourth republics, which engendered artificial political divisions within a hitherto isolated and porous region. Diplomacy with local clients was conducted primarily in Arabic, which was the traditional language of bureaucratic affairs. Mediation of disputes and inter-agency communication was served by interpreters contracted by the French government, who, according to Keenan, "documented a space of intercultural mediation," contributing much to preserving the indigenous cultural identities in the region.Jeremy Keenan, ed. (2013). ''The Sahara: Past, Present and Future''. Routledge,

Notes

References

Bibliography

* * Republished with a new preface Columbia University Press, 1990. * * * * * *

External links

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