Sahara

Sahara (الصحراء الكبرى)
The Great Desert
Desert
Sahara satellite hires.jpg
A satellite image of the Sahara by NASA World Wind.
Countries Algeria, Chad, Egypt, Eritrea, Libya, Mali, Mauritania, Morocco, Niger, Sudan, Tunisia, Western Sahara
Highest point Emi Koussi 11,204 ft (3,415 m)
 - coordinates 19°47′36″N 18°33′6″E / 19.79333°N 18.55167°E / 19.79333; 18.55167
Lowest point Qattara Depression −436 ft (−133 m)
 - coordinates 30°0′0″N 27°5′0″E / 30.00000°N 27.08333°E / 30.00000; 27.08333
Length 4,800 km (2,983 mi), E/W
Width 1,800 km (1,118 mi), N/S
Area 9,400,000 km2 (3,629,360 sq mi)
Biome Desert
This video over the Sahara Desert and the Middle East was taken by the crew of Expedition 29 on board the International Space Station.
Tadrart Acacus desert in western Libya, part of the Sahara.
The top image shows the Safsaf Oasis on the surface of the Sahara. The bottom (using radar) is the rock layer underneath, revealing black channels cut by the meandering of an ancient river that once fed the oasis.

The Sahara (Arabic: الصحراء الكبرى‎, aṣ-Ṣaḥrāʾ al-Kubrā , 'the Great Desert') is the world's hottest desert, and the third largest desert after Antarctica and the Arctic.[1] At over 9,400,000 square kilometres (3,600,000 sq mi), it covers most of North Africa, making it almost as large as China or the United States. The Sahara stretches from the Red Sea, including parts of the Mediterranean coasts to the Atlantic Ocean. To the south, it is delimited by the Sahel, a belt of semi-arid tropical savanna that composes the northern region of central and western Sub-Saharan Africa.

Some of the sand dunes can reach 180 metres (590 ft) in height.[2] The name comes from the plural Arabic language word for desert (صحارى ṣaḥārā [3][4] [ˈsˤɑħɑːrɑː]).[5][6]

OverviewEdit

The Sahara's boundaries are the Atlantic Ocean on the west, the Atlas Mountains and the Mediterranean on the north, the Red Sea on the east, and the Sudan and the valley of the Niger River on the south. The Sahara is divided into western Sahara, the central Ahaggar Mountains, the Tibesti Mountains, the Aïr Mountains (a region of desert mountains and high plateaus), Ténéré desert and the Libyan Desert (the most arid region). The highest peak in the Sahara is Emi Koussi (3,415 metres (11,204 ft)) in the Tibesti Mountains in northern Chad.

The Sahara is the largest desert on the African continent. The southern border of the Sahara is marked by a band of semiarid savanna called the Sahel; south of the Sahel lies Southern Sudan and the Congo River Basin. Most of the Sahara consists of rocky hamada; ergs (large areas covered with sand dunes) form only a minor part.

People lived on the edge of the desert thousands of years ago[7] since the last ice age. The Sahara was then a much wetter place than it is today. Over 30,000 petroglyphs of river animals such as crocodiles [8] survive, with half found in the Tassili n'Ajjer in southeast Algeria. Fossils of dinosaurs, including Afrovenator, Jobaria and Ouranosaurus, have also been found here. The modern Sahara, though, is not lush in vegetation, except in the Nile Valley, at a few oases, and in the northern highlands, where Mediterranean plants such as the olive tree are found to grow. The region has been this way since about 1600 BCE, after shifts in the Earth's axis increased temperatures and decreased precipitation.[9] Then, due to a climate change, the savannah changed into the sandy desert as we know it now.[citation needed]

Dominant ethnicities in the Sahara are various Berber groups including Tuareg tribes, various Arabized Berber groups such as the Hassaniya-speaking Maure (Moors, also known as Sahrawis, whose more known tribes are the Reguibat and the Znaga), including Toubou, Nubians, Zaghawa, Kanuri, Hausa, Songhai, and Fula/Fulani (French: Peul; Fula: Fulɓe). Important cities located in the Sahara include Nouakchott, the capital of Mauritania; Tamanrasset, Ouargla, Béchar, Hassi Messaoud, Ghardaïa, and El Oued in Algeria; Timbuktu in Mali; Agadez in Niger; Ghat in Libya; and Faya-Largeau in Chad.

GeographyEdit

A geographical map of Africa, showing the ecological break that defines the Saharan area.
An oasis in the Ahaggar Mountains. Oases support some life forms in extremely arid deserts.
An intense Saharan dust storm sent a massive dust plume northwestward over the Atlantic Ocean on March 2, 2003
Rocky mountains naturally sculpted by the wind

The Sahara covers large parts of Algeria, Chad, Egypt, Libya, Mali, Mauritania, Morocco, Niger, Western Sahara, Sudan and Tunisia. It is one of three distinct physiographic provinces of the African massive physiographic division.

The desert landforms of the Sahara are shaped by wind or by occasional rains and include sand dunes and dune fields or sand seas (erg), stone plateaus (hamada), gravel plains (reg), dry valleys, and salt flats (shatt or chott).[10] Unusual landforms include the Richat Structure in Mauritania.

Several deeply dissected mountains and mountain ranges, many volcanic, rise from the desert, including the Aïr Mountains, Ahaggar 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 range of northern Chad.

Most of the rivers and streams in the Sahara are seasonal or intermittent, the chief exception being the Nile River, which crosses the desert from its origins in central Africa to empty into the Mediterranean. Underground aquifers sometimes reach the surface, forming oases, including the Bahariya, Ghardaïa, Timimoun, Kufra, and Siwa.

The central part of the Sahara is hyper-arid, with little vegetation. The northern and southern reaches of the desert, along with the highlands, have areas of sparse grassland and desert shrub, with trees and taller shrubs in wadis where moisture collects.

To the north, the Sahara reaches to the Mediterranean Sea in Egypt and portions of Libya, but in Cyrenaica and the Maghreb, the Sahara borders Mediterranean forest, woodland, and scrub ecoregions of northern Africa, which have a Mediterranean climate characterized by a winter rainy season. According to the botanical criteria of Frank White[11] and geographer Robert Capot-Rey,[12][13] the northern limit of the Sahara corresponds to the northern limit of date palm cultivation and the southern limit of esparto, a grass typical of the Mediterranean climate portion of the Maghreb and Iberia. The northern limit also corresponds to the 100 mm (3.9 in) isohyet of annual precipitation.[14]

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 (a drought-tolerant member of the Chenopodiaceae), or northern limit of Cenchrus biflorus, a grass typical of the Sahel.[12][13] According to climatic criteria, the southern limit of the Sahara corresponds to the 150 mm (5.9 in) isohyet of annual precipitation (this is a long-term average, since precipitation varies annually).[14]

ClimateEdit

OverviewEdit

The Sahara is a harsh environment with extreme conditions. It is the world's largest subtropical hot desert, and the world's hottest desert. The Sahara has mainly a subtropical, hot desert climate (Köppen climate classification BWh) especially in the north of the desert. The south part also has a hot desert climate but with more tropical features. Both climates have mainly oppressively hot, sunny and dry conditions. The Sahara is one of the driest deserts in the world and receives a very to an extremely low annual average precipitation. Some parts of the Sahara, like southern Egypt or southern Libya, have the lowest rain amount recorded on Earth (less than 5 mm of rain) and are nearly as dry as the Atacama Desert, considered as the driest place. The Sahara desert is considered as a real desert because it has arid (between 50 mm and 150 mm of rain annually) and hyperarid zones (between 0 mm and 50 mm of rain annually), and even a semi-arid zone (between 150 mm and 250 mm of rain), called the Sahel. The Sahara is the desert and the Sahel is the steppe. The relative humidity is very to extremely low, often between 4% and 25% in summer and between 25% and 45% in winter. The least humid places can have a relative humidity always lower than 20%.

The Sahara has globally very long and very to extremely hot summers, with average high temperatures between 38 °C (100.4 °F) and 46 °C (114.8 °F) (and even more in the hottest regions) and all with a scorching sun, often for more than 3 months, while the average low temperatures remain generally between 21 °C (69.8 °F) and 29 °C (84.2 °F). Most of the Sahara reaches more than 40 °C (104 °F) during summer. During heat waves, the high temperatures can infrequently rise to over 50 °C (122 °F). The winters stay very hot to quite hot, with average high temperatures between 20 °C (68 °F) and 28 °C (82.4 °F), but the average low temperature is very low, often fluctuating from 5 °C (41 °F) to 15 °C (59 °F). The hottest zones in summer can have average daytime temperatures around 48 °C (118.4 °F) during the hottest month, and the warmest places in winter can easily remain above 30 °C (86 °F) during the coldest month. There are large diurnal temperature ranges between the day and the night because of the clear skies and the dry atmosphere. Southern and central Algeria and northern Mali are the places with the most extreme heat.

The Sahara contains the sunniest places worldwide, with a very to an extremely high sunshine duration year-round, between 3,000 hours (68% of the time) and 4,000 hours (more than 90% of the time). The Eastern Desert (Chad, Libya, Egypt, Sudan and Niger) is the sunniest part of the Sahara, with some desert areas which could have a sunshine duration well above 4,000 hours per year[15][16]. The hyperarid part of the Sahara gets always over 3,500 hours of sun per year everywhere. For example Aswan, Egypt has 3,864 hours of sunshine; Luxor, Egypt has 3,833 hours of sunshine; Faya-Largeau, Chad has about 3,792 hours of sun; Bilma, Niger has 3,699 hours of sunlight; Tindouf, Algeria has a bit more than 3,600 hours; In Salah, Algeria records more than 3,650 hours; Taoudeni, Mali reaches nearly 3,700 hours; and Wadi Halfa, Sudan has around 3,900 hours of sun annually; Khartoum, Sudan has 3,731 hours of sun; Abu Hamad, Sudan has 3,763 hours of sunlight annually[17][18] Days with no sun are scarce in the Sahara and usually occur from time to time, on locatized days. The only area which has a comparable sunshine duration is Southwestern United States, with many places in Arizona, Nevada and California.

Located in the trade winds belt, the region is subject to winds that are frequently strong and that blow constantly from the northeast between a subtropical high-pressure cell and an equatorial low-pressure cell. As air moves downward from the high-pressure into the low-pressure cell, it becomes hotter and drier. The scorching, desiccating and sometimes dust-laden winds are sometimes felt north and south of the desert, where they are variously known as sirocco, khamsin, simoom, chergui and harmattan. The northern slopes of the Atlas Mountains and some other minor mountain ranges intercept most of the moisture from winds blowing inshore from the Mediterranean Sea and from the Atlantic Ocean.

The very high temperatures all year round, the strong and constant sunshine, the absence of precipitation, the very low humidity, and the dry winds cause very high theoretical levels of evaporation, between 2,000mm (2m) and 6,000mm (6m). The subtropical ridge and the continental trade winds are largely responsible of the Sahara desert climate.

ExamplesEdit

Climate data for Atar, Mauritania
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Average high °C (°F) 28
(82)
30
(86)
32
(90)
34
(93)
38
(100)
41
(106)
42
(108)
41
(106)
40
(104)
37
(99)
32
(90)
28
(82)
35.3
(95.5)
Daily mean °C (°F) 20.5
(68.9)
22
(72)
24
(75)
26.5
(79.7)
30
(86)
33.5
(92.3)
34.5
(94.1)
34
(93)
33
(91)
30
(86)
25
(77)
21
(70)
27.83
(82.08)
Average low °C (°F) 13
(55)
14
(57)
16
(61)
19
(66)
22
(72)
26
(79)
27
(81)
27
(81)
26
(79)
23
(73)
18
(64)
14
(57)
20.4
(68.8)
Precipitation mm (inches) 2
(0.08)
2
(0.08)
1
(0.04)
0
(0)
0
(0)
2
(0.08)
6
(0.24)
25
(0.98)
24
(0.94)
4
(0.16)
3
(0.12)
4
(0.16)
73
(2.88)
Avg. rainy days 1 1 0 0 0 0 1 2 2 0 1 0 8
 % humidity 32 28 27 24 21 21 30 31 34 27 24 32 27.6
Mean monthly sunshine hours 256 260 298 304 315 307 302 297 295 296 281 266 3,477
Source #1: Weather2Travel[19]
Source #2: Voodoo Skies for record temperatures[20]
Climate data for Aswan, Egypt
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Average high °C (°F) 22.9
(73.2)
25.2
(77.4)
29.5
(85.1)
34.9
(94.8)
38.9
(102)
41.4
(106.5)
41.1
(106)
40.9
(105.6)
39.3
(102.7)
35.9
(96.6)
29.1
(84.4)
24.3
(75.7)
33.62
(92.5)
Daily mean °C (°F) 15.3
(59.5)
17.5
(63.5)
21.8
(71.2)
27
(81)
31.4
(88.5)
33.5
(92.3)
33.6
(92.5)
33.2
(91.8)
31.2
(88.2)
27.7
(81.9)
21.5
(70.7)
16.9
(62.4)
25.88
(78.63)
Average low °C (°F) 8.7
(47.7)
10.2
(50.4)
13.8
(56.8)
18.9
(66)
23
(73)
25.2
(77.4)
26
(79)
25.8
(78.4)
24
(75)
20.6
(69.1)
15.0
(59)
10.5
(50.9)
18.47
(65.22)
Precipitation mm (inches) 0
(0)
0
(0)
0
(0)
0
(0)
0.1
(0.004)
0
(0)
0
(0)
0.7
(0.028)
0
(0)
0.6
(0.024)
0
(0)
0
(0)
1.4
(0.056)
Avg. precipitation days 0 0 0 0 0.1 0 0 0.5 0 0.25 0 0 0.85
 % humidity 40 32 24 19 17 16 18 21 22 27 36 42 26.17
Mean monthly sunshine hours 298 281 322 316 347 363 375 360 298 315 300 289 3,864
Source #1: World Meteorological Organization,[21] Climate Charts for mean temperatures and another source for humidity[22]
Source #2: The Weather Network,[23] Voodoo Skies for record temperatures[20]
Climate data for In Salah, Algeria
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Average high °C (°F) 21.6
(70.9)
25.1
(77.2)
28.6
(83.5)
33.2
(91.8)
38.0
(100.4)
43.5
(110.3)
44.7
(112.5)
44.0
(111.2)
40.3
(104.5)
34.1
(93.4)
27.1
(80.8)
21.9
(71.4)
33.51
(92.33)
Daily mean °C (°F) 14.3
(57.7)
17.6
(63.7)
21.0
(69.8)
25.2
(77.4)
30.1
(86.2)
35.6
(96.1)
37.0
(98.6)
36.5
(97.7)
33.1
(91.6)
26.9
(80.4)
20.1
(68.2)
14.9
(58.8)
26.03
(78.85)
Average low °C (°F) 7.1
(44.8)
10.0
(50)
13.3
(55.9)
17.1
(62.8)
22.1
(71.8)
27.6
(81.7)
29.2
(84.6)
28.8
(83.8)
25.8
(78.4)
19.7
(67.5)
13.0
(55.4)
7.8
(46)
18.46
(65.22)
Precipitation mm (inches) 3.7
(0.146)
3.5
(0.138)
1.2
(0.047)
1.6
(0.063)
0.5
(0.02)
0.1
(0.004)
0.0
(0)
0.5
(0.02)
0.2
(0.008)
1.2
(0.047)
0.5
(0.02)
2.7
(0.106)
15.7
(0.619)
 % humidity 41.3 35.0 27.1 23.8 20.8 17.7 15.6 16.8 21.9 29.9 35.8 41.9 27.3
Source #1: NOAA (1964-1990)[24]
Source #2: climatebase.ru (humidity)[25]
Climate data for El Guettara, Mali
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Average high °C (°F) 26.1
(79)
29.8
(85.6)
32.3
(90.1)
39.8
(103.6)
42.4
(108.3)
46.4
(115.5)
46.7
(116.1)
45.4
(113.7)
43.6
(110.5)
38.5
(101.3)
31.5
(88.7)
26.5
(79.7)
37.42
(99.34)
Daily mean °C (°F) 18
(64)
20.9
(69.6)
24.3
(75.7)
29.8
(85.6)
33
(91)
37.1
(98.8)
37.9
(100.2)
36.8
(98.2)
35.4
(95.7)
30.3
(86.5)
23.8
(74.8)
18.6
(65.5)
28.83
(83.8)
Average low °C (°F) 9.9
(49.8)
12.1
(53.8)
16.3
(61.3)
19.9
(67.8)
23.7
(74.7)
27.8
(82)
29.1
(84.4)
28.3
(82.9)
27.3
(81.1)
22.1
(71.8)
16.1
(61)
10.8
(51.4)
20.28
(68.5)
Precipitation mm (inches) 0
(0)
0
(0)
0
(0)
0
(0)
0
(0)
0
(0)
0
(0)
8
(0.31)
0
(0)
0
(0)
0
(0)
0
(0)
8
(0.31)
Source: Climate data for El Guettara
Climate data for Khartoum, Sudan
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Average high °C (°F) 29.8
(85.6)
33.0
(91.4)
36.8
(98.2)
40.1
(104.2)
41.9
(107.4)
41.3
(106.3)
38.4
(101.1)
37.3
(99.1)
39.1
(102.4)
39.3
(102.7)
35.2
(95.4)
31.8
(89.2)
37
(98.58)
Daily mean °C (°F) 23.5
(74.3)
25
(77)
28.7
(83.7)
31.9
(89.4)
34.5
(94.1)
34.3
(93.7)
32.3
(90.1)
31.5
(88.7)
32.5
(90.5)
32.4
(90.3)
28.1
(82.6)
25.5
(77.9)
30.02
(86.03)
Average low °C (°F) 15.6
(60.1)
17.0
(62.6)
20.5
(68.9)
23.6
(74.5)
27.1
(80.8)
27.3
(81.1)
25.9
(78.6)
25.3
(77.5)
26.0
(78.8)
25.5
(77.9)
21.0
(69.8)
17.1
(62.8)
22.66
(72.78)
Precipitation mm (inches) 0
(0)
0
(0)
0
(0)
0
(0)
.4
(0.016)
4.0
(0.157)
46.3
(1.823)
75.2
(2.961)
25.4
(1)
4.8
(0.189)
.7
(0.028)
0
(0)
156.8
(6.174)
Avg. precipitation days (≥ 0.1 mm) 0 0 .1 .1 .9 1.2 4.8 4.8 3.2 1.2 0 0 16.3
 % humidity 27 22 17 16 19 28 43 49 40 28 27 30 28.8
Mean monthly sunshine hours 341 311 310 330 300 300 279 279 300 310 330 341 3,731
Source #1: World Meteorological Organisation (UN)[26]
Source #2: BBC Weather[27]
Climate data for Tindouf, Algeria
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Average high °C (°F) 20.7
(69.3)
23.6
(74.5)
27.6
(81.7)
30.2
(86.4)
33.8
(92.8)
38.7
(101.7)
43.3
(109.9)
42.4
(108.3)
37.6
(99.7)
31.8
(89.2)
25.9
(78.6)
21.4
(70.5)
31.42
(88.55)
Daily mean °C (°F) 13.4
(56.1)
16.2
(61.2)
20.1
(68.2)
22.4
(72.3)
25.7
(78.3)
30.1
(86.2)
35.1
(95.2)
34.7
(94.5)
30.0
(86)
24.6
(76.3)
18.7
(65.7)
14.2
(57.6)
23.77
(74.8)
Average low °C (°F) 6.7
(44.1)
9.0
(48.2)
12.6
(54.7)
14.2
(57.6)
16.9
(62.4)
20.9
(69.6)
26.1
(79)
26.5
(79.7)
22.5
(72.5)
17.5
(63.5)
12.1
(53.8)
7.9
(46.2)
16.08
(60.94)
Precipitation mm (inches) 0.1
(0.004)
0.3
(0.012)
0.2
(0.008)
0.1
(0.004)
2.0
(0.079)
0.2
(0.008)
0.0
(0)
2.5
(0.098)
10.0
(0.394)
3.4
(0.134)
0.3
(0.012)
0.3
(0.012)
19.4
(0.765)
 % humidity 44.9 40.8 34.8 35.4 35.2 30.3 22.8 24.5 32.3 28.1 43.8 49.6 35.21
Mean monthly sunshine hours 257 263 301 342 353 357 338 319 282 288 249 254 3,603
Source: climatebase.ru[25]
Climate data for Bilma, Niger
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Average high °C (°F) 25.4
(77.7)
28.8
(83.8)
33.1
(91.6)
37.9
(100.2)
41.2
(106.2)
42.3
(108.1)
41.1
(106)
40.2
(104.4)
39.8
(103.6)
36.6
(97.9)
30.8
(87.4)
26.7
(80.1)
35.3
(95.5)
Daily mean °C (°F) 17.3
(63.1)
19.9
(67.8)
24.5
(76.1)
29.1
(84.4)
32.4
(90.3)
33.4
(92.1)
33.3
(91.9)
33
(91)
31.6
(88.9)
27.7
(81.9)
22.2
(72)
18.1
(64.6)
26.8
(80.2)
Average low °C (°F) 8.5
(47.3)
10.8
(51.4)
15.5
(59.9)
20.1
(68.2)
23.3
(73.9)
24.4
(75.9)
25.4
(77.7)
25.4
(77.7)
22.7
(72.9)
18.6
(65.5)
12.5
(54.5)
9.4
(48.9)
18.1
(64.6)
Precipitation mm (inches) 0
(0.00)
0
(0.00)
0
(0.00)
0
(0.00)
0
(0.00)
0
(0.00)
2.5
(0.10)
7.6
(0.30)
2.5
(0.10)
0
(0.00)
0
(0.00)
0
(0.00)
12.7
(0.50)
 % humidity 17 14 12 10 11 13 18 24 16 14 15 19 15.3
Source: Climate Data [28]
Climate data for Sbaa, Algeria
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Average high °C (°F) 20.1
(68.2)
22.9
(73.2)
27.5
(81.5)
32.7
(90.9)
36.7
(98.1)
43.0
(109.4)
46.2
(115.2)
44.4
(111.9)
40.3
(104.5)
33.0
(91.4)
25.3
(77.5)
21.8
(71.2)
32.83
(91.08)
Daily mean °C (°F) 12.1
(53.8)
14.9
(58.8)
19.1
(66.4)
24.2
(75.6)
28.2
(82.8)
34.2
(93.6)
36.9
(98.4)
35.6
(96.1)
32.1
(89.8)
25.3
(77.5)
18.0
(64.4)
11.4
(52.5)
24.33
(75.81)
Average low °C (°F) 4.2
(39.6)
6.9
(44.4)
10.8
(51.4)
15.8
(60.4)
19.7
(67.5)
25.5
(77.9)
28.0
(82.4)
27.1
(80.8)
24.1
(75.4)
17.6
(63.7)
10.8
(51.4)
5.8
(42.4)
16.36
(61.44)
Precipitation mm (inches) 1
(0.04)
1
(0.04)
3
(0.12)
1
(0.04)
1
(0.04)
0
(0)
0
(0)
1
(0.04)
1
(0.04)
3
(0.12)
2
(0.08)
2
(0.08)
16
(0.64)
Source: Climate Data[29]
Climate data for Taoudenni, Mali
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Average high °C (°F) 26.2
(79.2)
30.1
(86.2)
32.5
(90.5)
39.9
(103.8)
42.6
(108.7)
46.8
(116.2)
47.9
(118.2)
46.6
(115.9)
44.1
(111.4)
38.6
(101.5)
31.7
(89.1)
26.5
(79.7)
37.79
(100.03)
Daily mean °C (°F) 18
(64.4)
21.2
(70.2)
24.4
(75.9)
29.8
(85.6)
33.1
(91.6)
37.2
(99.0)
38.7
(101.7)
37.8
(100.0)
35.8
(96.4)
30.4
(86.7)
24
(75.2)
18.7
(65.7)
29.09
(84.37)
Average low °C (°F) 9.9
(49.8)
12.3
(54.1)
16.4
(61.5)
19.8
(67.6)
23.7
(74.7)
27.7
(81.9)
29.6
(85.3)
29
(84.2)
27.6
(81.7)
22.2
(72.0)
16.3
(61.3)
10.9
(51.6)
20.45
(68.81)
Precipitation mm (inches) 0
(0)
0
(0)
0
(0)
0
(0)
0
(0)
0
(0)
0
(0)
7.1
(0.28)
0
(0)
0
(0)
0
(0)
0
(0)
7.1
(0.28)
Avg. precipitation days 0 0 0 0 0 0 0 4 0 0 0 0 4
Mean monthly sunshine hours 285 278 328 330 337 322 338 317 296 299 275 266 3,671
Source: [30]
Climate data for Luxor, Egypt
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Average high °C (°F) 23
(73)
25.4
(77.7)
27.4
(81.3)
35
(95)
39.2
(102.6)
41.4
(106.5)
41.1
(106)
40.4
(104.7)
38.8
(101.8)
35.3
(95.5)
28.9
(84)
24.4
(75.9)
33.36
(92)
Daily mean °C (°F) 15.0
(59)
16.2
(61.2)
20.5
(68.9)
25.6
(78.1)
29.6
(85.3)
32.2
(90)
32.3
(90.1)
31.8
(89.2)
29.7
(85.5)
25.9
(78.6)
20.8
(69.4)
16.1
(61)
24.64
(76.36)
Average low °C (°F) 7.0
(44.6)
8.1
(46.6)
12.4
(54.3)
16
(61)
20.2
(68.4)
22.6
(72.7)
23.6
(74.5)
23.2
(73.8)
21.3
(70.3)
17.3
(63.1)
13.4
(56.1)
8.1
(46.6)
16.1
(61)
Precipitation mm (inches) 0
(0)
0
(0)
0
(0)
0
(0)
0
(0)
0
(0)
0
(0)
0
(0)
0
(0)
1
(0.04)
0
(0)
0
(0)
1
(0.04)
 % humidity 55 47 39 31 29 27 30 33 37 43 51 57 39.92
Mean monthly sunshine hours 290 279 320 313 345 362 373 360 295 310 300 286 3,833
Source #1: Climate Charts[31]
Source #2: Voodoo Skies for record temperatures,[20] Weather2Travel for sunshine[32]
Climate data for Abu Hamad, Sudan
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Average high °C (°F) 28
(82)
30
(86)
34
(93)
38
(100)
41
(105)
43
(109)
41
(105)
41
(105)
42
(107)
39
(102)
33
(91)
29
(84)
36.6
(97.4)
Daily mean °C (°F) 20
(68)
21.5
(70.7)
25.5
(77.9)
29.5
(85.1)
32.5
(90.5)
35
(95)
33.5
(92.3)
34
(93)
34.5
(94.1)
31
(88)
26
(79)
21.5
(70.7)
28.71
(83.69)
Average low °C (°F) 12
(53)
13
(55)
17
(62)
21
(69)
24
(75)
27
(80)
26
(78)
27
(80)
27
(80)
23
(73)
19
(66)
14
(57)
20.8
(69)
Precipitation mm (inches) 0
(0)
0
(0)
0
(0)
0
(0)
0
(0)
0
(0)
3
(0.12)
8
(0.31)
0
(0)
0
(0)
0
(0)
0
(0)
11
(0.43)
 % humidity 31 24 19 17 16 15 20 25 20 22 31 33 22.8
Source: Weatherbase [33]
Climate data for Ghat, Libya
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Average high °C (°F) 21
(70)
24
(76)
28
(83)
34
(93)
37
(99)
41
(106)
41
(106)
41
(105)
38
(101)
34
(94)
28
(83)
23
(73)
32.5
(90.8)
Daily mean °C (°F) 14
(57)
16.5
(61.7)
20.5
(68.9)
25.5
(77.9)
30
(86)
33.5
(92.3)
34
(93)
33.5
(92.3)
31
(88)
26.5
(79.7)
21
(70)
16
(61)
25.17
(77.32)
Average low °C (°F) 7
(44)
9
(48)
13
(55)
17
(63)
23
(73)
26
(79)
26
(78)
26
(78)
24
(76)
19
(67)
14
(58)
9
(48)
17.8
(63.9)
Precipitation mm (inches) 8
(0.31)
0
(0)
0
(0)
0
(0)
5
(0.2)
0
(0)
0
(0)
0
(0)
0
(0)
0
(0)
0
(0)
0
(0)
13
(0.51)
Source: Weatherbase [33]
Climate data for Timiaouine, Algeria
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Average high °C (°F) 27.6
(81.7)
30.4
(86.7)
35.2
(95.4)
38.7
(101.7)
42.2
(108)
42.8
(109)
42.7
(108.9)
41.2
(106.2)
41
(106)
38.3
(100.9)
33.2
(91.8)
29
(84)
36.86
(98.36)
Daily mean °C (°F) 21
(70)
23.3
(73.9)
27.8
(82)
31.6
(88.9)
35
(95)
36.3
(97.3)
35.9
(96.6)
34.6
(94.3)
34.5
(94.1)
31.9
(89.4)
26.3
(79.3)
22.3
(72.1)
30.04
(86.07)
Average low °C (°F) 14.4
(57.9)
16.2
(61.2)
20.4
(68.7)
24.6
(76.3)
27.8
(82)
29.8
(85.6)
29.2
(84.6)
28.1
(82.6)
28.1
(82.6)
25.5
(77.9)
19.5
(67.1)
15.6
(60.1)
23.27
(73.88)
Precipitation mm (inches) 1
(0.04)
0
(0)
0
(0)
0
(0)
1
(0.04)
2
(0.08)
6
(0.24)
17
(0.67)
10
(0.39)
1
(0.04)
0
(0)
0
(0)
38
(1.5)
Source: Storm247[34]
Climate data for Agadez, Niger
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Average high °C (°F) 28
(82.4)
31.5
(88.7)
35.4
(95.7)
39
(102.2)
41.2
(106.2)
41
(105.8)
38.9
(102.0)
37.4
(99.3)
38.5
(101.3)
37.2
(99.0)
32.3
(90.1)
29.1
(84.4)
35.8
(96.4)
Daily mean °C (°F) 20.1
(68.2)
22.7
(72.9)
27.2
(81.0)
31.4
(88.5)
33.9
(93.0)
33.6
(92.5)
31.9
(89.4)
30.6
(87.1)
31.6
(88.9)
29.6
(85.3)
24.7
(76.5)
21
(69.8)
28.3
(82.9)
Average low °C (°F) 11.5
(52.7)
13.9
(57.0)
18.1
(64.6)
22.9
(73.2)
25.8
(78.4)
26.2
(79.2)
24.9
(76.8)
24
(75.2)
24
(75.2)
21.6
(70.9)
15.8
(60.4)
13
(55.4)
20.2
(68.3)
Precipitation mm (inches) 0
(0.00)
0
(0.00)
0
(0.00)
2
(0.08)
5.1
(0.20)
9.9
(0.39)
35.1
(1.38)
50
(1.97)
7.9
(0.31)
0
(0.00)
0
(0.00)
0
(0.00)
109.2
(4.30)
 % humidity 16 13 12 10 11 13 18 24 16 14 15 19 15.1
Mean monthly sunshine hours 297.6 282.5 294.5 288.0 297.6 270.0 288.3 285.2 285.0 306.9 303.0 294.5 3,493.1
Source #1: Climate Data [35]
Source #2: Hong Kong Observatory (sun only 1961-1990).[36]

HistoryEdit

The climate of the Sahara has undergone enormous variations between wet and dry over the last few hundred thousand years.[37] This is due to a 41000 year cycle in which the tilt of the earth changes between 22° and 24.5°.[38] At present (2000 CE), we are in a dry period, but it is expected that the Sahara will become green again in 15000 years (17000 CE).

During the last glacial period, the Sahara was even bigger than it is today, extending south beyond its current boundaries.[39] 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.[40]

Once the ice sheets were gone, the northern Sahara dried out. In the southern Sahara though, the drying trend was soon counteracted by the monsoon, which brought rain further north than it does today. In this period, there was still a monsoon climate in the Sahara. Monsoons form by heating of air over the land during summer. The hot air rises and pulls in cool, wet air from the ocean, which causes rain. Thus, though it seems counterintuitive, the Sahara was wetter when it received more insolation in the summer. This was caused by a stronger tilt in Earth's axis of orbit than today (24.5 degree tilt vs the 23.4° tilt today[38]), and perihelion occurred at the end of July around 7000 BCE.[41]

By around 4200 BCE, the monsoon retreated south to approximately where it is today,[9] leading to the gradual desertification of the Sahara.[42] The Sahara is now as dry as it was about 13,000 years ago.[37] These conditions are responsible for what has been called the Sahara pump theory.

The Sahara has one of the harshest climates in the world. The prevailing north-easterly wind often causes sand storms and dust devils.[43] When this wind reaches the Mediterranean, it is known as sirocco and often reaches hurricane speeds in North Africa and southern Europe. Half of the Sahara receives less than 20 mm (0.79 in) of rain per year, and the rest receives up to 100 mm (3.9 in) per year.[44] The rainfall happens very rarely, but when it does it is usually torrential when it occurs after long dry periods. The southern boundary of the Sahara, as measured by rainfall, was observed to both advance and retreat between 1980 and 1990. As a result of drought in the Sahel, the southern boundary moved south 130 kilometers (81 mi) overall during that period.[45]

Recent signals indicate that the Sahara and surrounding regions are greening because of increased rainfall. Satellite imaging shows extensive regreening of the Sahel between 1982 and 2002, and in both Eastern and Western Sahara a more than 20-year-long trend of increased grazing areas and flourishing trees and shrubs has been observed by climate scientist Stefan Kröpelin.[46]

Snow and iceEdit

On February 18, 1979, snow fell in several places in southern Algeria, including a half-hour snowstorm that stopped traffic in Ghardaïa, and was reported as being "for the first time in living memory".[47] The snow was gone within hours.[48] Several Saharan mountain ranges, however, receive snow more regularly. Although relative humidity is low in the arid environment, the absolute humidity is high enough for moisture to condense when driven up a mountain range. In winter, temperatures drop low enough on the Tahat summit to cause snow on average every three years; the Tibesti Mountains receive snow on peaks over 2,500 meters (8,200 ft) once every seven years on average.[49][50]

On January 18, 2012, snow fell in several places in western Algeria. Strong winds blew the snow across roads and buildings in Béchar Province.[51]

EcoregionsEdit

The major topographic features of the Saharan region.

The Sahara comprises several distinct ecoregions, and with their variations in temperature, rainfall, elevation, and soil, they 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 39,900 square kilometers (15,400 sq mi) in Western Sahara and Mauritania.[52]

The North Saharan steppe and woodlands is along the northern desert, next to the Mediterranean forests, woodlands, and scrub 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 1,675,300 square kilometers (646,800 sq mi) in Algeria, Egypt, Libya, Mauritania, Morocco, Tunisia, and Western Sahara.[53]

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 4,639,900 square km (1,791,500 square miles) of Algeria, Chad, Egypt, Libya, Mali, Mauritania, Niger, and Sudan.[10]

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 100 to 200 mm (3.9 to 7.9 in) 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 1,101,700 km2 (425,400 mi2) in Algeria, Chad, Mali, Mauritania, and Sudan.[54]

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 258,100 km2 (99,700 mi2), mostly in the Tassili n'Ajjer of Algeria, with smaller enclaves in the Aïr of Niger, the Dhar Adrar of Mauritania, and the Adrar des Iforas of Mali and Algeria.[55]

The Tibesti-Jebel Uweinat montane xeric woodlands ecoregion consists of the Tibesti and Jebel Uweinat highlands. Higher and more regular rainfall and cooler temperatures support woodlands and shrublands of palms, acacias, myrtle, oleander, tamarix, and several rare and endemic plants. The ecoregion covers 82,200 km2 (31,700 mi2) in the Tibesti of Chad and Libya, and Jebel Uweinat on the border of Egypt, Libya, and Sudan.[56]

The Saharan halophytics is an area of seasonally flooded saline depressions which is home to halophytic (salt-adapted) plant communities. The Saharan halophytics cover 54,000 km2 (20,800 mi2), including the Qattara and Siwa depressions in northern Egypt, the Tunisian salt lakes of central Tunisia, Chott Melghir in Algeria, and smaller areas of Algeria, Mauritania, and Western Sahara.[57]

The Tanezrouft is one of the harshest regions on Earth and the driest in the Sahara, with no vegetation and very little life. It is along the borders of Algeria, Niger and Mali, west of the Hoggar mountains.

Flora and faunaEdit

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.[58]

The Saharan flora comprises around 2800 species of vascular plants. Approximately a quarter of these are endemic. About half of these species are common to the flora of the Arabian deserts.[59]

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 evapo-transpiration. Plant leaves may dry out totally and then recover.

Camels in the Guelta d'Archei, in north-eastern Chad.

Several species of fox live in the Sahara, including the fennec fox, pale fox and Rüppell's fox. The addax, 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, Niger, Mali, Benin, and Burkina Faso. 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 and acacias. They are unusually pale.[60][61]

An Ubari oasis lake, with native grasses and Date palms.

Other animals include the monitor lizards, hyrax, sand vipers, and small populations of African wild dog,[62] in perhaps only 14 countries[63] and ostrich. There exist other animals in the Sahara (birds in particular) such as African silverbill and black-faced firefinch, among others. There are also small desert crocodiles in Mauritania and the Ennedi Plateau of Chad.[64]

The deathstalker scorpion can be 10 cm (3.9 in) 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 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.[65]

Dromedary camels and goats 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 nomads.

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.

HistoryEdit

NubiansEdit

Beni Isguen, a holy city surrounded by thick walls in the Algerian Sahara.

During the Neolithic 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 peoples who inhabited what is now called Nubia, 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.[66] Megaliths found at Nabta Playa are overt examples of probably the world's first known archaeoastronomy devices, predating Stonehenge by some 2,000 years.[67] 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.[68]

EgyptiansEdit

By 6000 BCE predynastic Egyptians 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 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.[69] 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 dead were buried facing due west.[70]

By 3400 BCE, the Sahara was as dry as it is today, due to reduced precipitation and higher temperatures resulting from a shift in the Earth's orbit,[9] and it became a largely impenetrable barrier to humans, with only scattered settlements around the oases but little trade or commerce through the desert. The one major exception was the Nile Valley. The Nile, however, was impassable at several cataracts, making trade and contact by boat difficult.

PhoeniciansEdit

The people of Phoenicia, who flourished from 1200-800 BCE, created a confederation of kingdoms across the entire Sahara to Egypt. They generally settled along the Mediterranean coast, as well as the Sahara, among the people of Ancient Libya, who were the ancestors of people who speak Berber languages in North Africa and the Sahara today, including the Tuareg of the central Sahara.

Azalai salt caravan. The French reported that the 1906 caravan numbered 20,000 camels.

The Phoenician alphabet seems to have been adopted by the ancient Libyans of north Africa, and Tifinagh is still used today by Berber-speaking Tuareg camel herders of the central Sahara.

Sometime between 633 BCE and 530 BCE, Hanno the Navigator either established or reinforced Phoenician colonies in Western Sahara, but all ancient remains have vanished with virtually no trace.

GreeksEdit

By 500 BCE, Greeks arrived in the desert. Greek traders spread along the eastern coast of the desert, establishing trading colonies along the Red Sea. The Carthaginians 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 a constant concern of those living on the edge of the desert.

Urban civilizationEdit

Market on the main square of Ghardaïa (1971).

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.[37] 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 (which 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 the Garamantes, 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 aquifers and could no longer sustain the effort to extend the tunnels further into the mountains.[71]

BerbersEdit

Zawiya at the entrance of Taghirt, Algeria

The Berber people occupied (and still occupy) much of the Sahara. The Garamantes Berbers built a prosperous empire in the heart of the desert.[72] The Tuareg nomads continue, to the present day, to inhabit and move across wide Sahara surfaces.

Islamic expansionEdit

The Byzantine Empire ruled the northern shores of the Sahara from the 5th to the 7th century. After the Muslim conquest of Arabia (Arabian peninsula) the Muslim conquest of North Africa began in the mid 7th to early 8th centuries, Islamic influence expanded rapidly on the Sahara. By the end of 641 all of Egypt was in Muslim hands. The trade across the desert intensified. A significant slave trade crossed the desert. It has been estimated that from the 10th to the 19th century some 6,000 to 7,000 slaves were transported north each year.[73]

The Tuareg once controlled the central Sahara desert and its trade.

This trade through Sahara persisted for several centuries until the development in Europe of the caravel allowed ships, first from Portugal and soon from all of Western Europe, to sail around the desert and gather the resources from the source in Guinea. The Sahara was rapidly marginalized.

Ottoman Turkish eraEdit

In the 16th century the northern fringe of the Sahara, such as coastal regencies in present day Algeria 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. 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. Trade exploited the Ottoman land routes to handle the spices, gold and silk from the East, manufactures 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 colonialismEdit

European colonialism in the Sahara began in the 19th century. France conquered the regency of Algiers from the Ottomans in 1830, and French rule spread south from Algeria and eastwards from Senegal into the upper Niger to include present-day Algeria, Chad, Mali then French Sudan including Timbuktu, Mauritania, Morocco (1912), Niger, and Tunisia (1881). By the beginning of the twentieth 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.[74]

The French Colonial Empire was the dominant presence in the Sahara. It established regular air links from Toulouse (HQ of famed Aéropostale), to Oran and over the Hoggar to Timbuktu and West to Bamako and Dakar, as well as trans-Sahara bus services run by La Companie Transsaharienne (est. 1927).[75] 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.[76]

Egypt, under Muhammad Ali and his successors, conquered Nubia in 1820–22, founded Khartoum 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. After its capture by British troops in 1898, the Sudan became an Anglo-Egyptian condominium.

Spain captured present-day Western Sahara after 1874, although Rio del Oro remained largely under Tuareg influence. In 1912, Italy captured parts of what was to be named Libya from the Ottomans. To promote the Roman Catholic religion in the desert, Pope Pius IX 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.

Breakup of the empires and afterwardsEdit

A natural rock arch in south western Libya.
The Sahara today.

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: 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, and Morocco continues to hold the territory.

In the post-World War II era, several mines and communities have developed to utilize the desert's natural resources. These include large deposits of oil and natural gas in Algeria and Libya and large deposits of phosphates in Morocco and Western Sahara.

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 from Tripoli in Libya to N'Djamena in Chad, and the Cairo – Cape Town Highway which follows the Nile. Each of these highways is partially complete, with significant gaps and unpaved sections.

People and languagesEdit

A 19th-century engraving of an Arab slave-trading caravan transporting black African slaves across the Sahara.

Arabic dialects are the most widely spoken languages in the Sahara, from the Atlantic to the Red Sea. Berber people are found from western Egypt to Morocco, including the Tuareg pastoralists of the central Sahara. The Beja live in the Red Sea Hills of southeastern Egypt and eastern Sudan. Arabic, Berber and its variants now regrouped under the term Amazigh (which includes the Guanche language spoken by the original Berber inhabitants of the Canary Islands) and Beja languages are part of the Afro-Asiatic or Hamito-Semitic family.[citation needed]

See alsoEdit

NotesEdit

  1. ^ "Largest Desert in the World". Retrieved 2011-12-30. 
  2. ^ Arthur N. Strahler and Alan H. Strahler. (1987) Modern Physical Geography Third Edition. New York: John Wiley & Sons. Page 347
  3. ^ "Sahara." Online Etymology Dictionary. Douglas Harper, Historian. Retrieved June 25, 2007.
  4. ^ "English-Arabic online dictionary". Online.ectaco.co.uk. 2006-12-28. Retrieved 2010-06-12. 
  5. ^ Wehr, Hans (1994). A Dictionary of Modern Written Arabic (Arabic-English) (4th ed.). Wiesbaden: Otto Harrassowitz. p. 589. ISBN 0-87950-003-4. 
  6. ^ al-Ba‘labakkī, Rūḥī (2002). al-Mawrid: Qāmūs ‘Arabī-Inklīzī (in Arabic) (16th ed.). Beirut: Dār al-‘Ilm lil-Malāyīn. p. 689. 
  7. ^ Discover Magazine, 2006-Oct.
  8. ^ National Geographic News, 2006-06-17.
  9. ^ a b c Sahara's Abrupt Desertification Started by Changes in Earth's Orbit, Accelerated by Atmospheric and Vegetation Feedbacks.
  10. ^ a b "Sahara desert". Terrestrial Ecoregions. World Wildlife Fund. Retrieved December 30, 2007. 
  11. ^ Wickens, Gerald E. (1998) Ecophysiology of Economic Plants in Arid and Semi-Arid Lands. Springer, Berlin. ISBN 978-3-540-52171-6
  12. ^ a b Grove, A.T., Nicole (1958,2007). "The Ancient Erg of Hausaland, and Similar Formations on the South Side of the Sahara". The Geographical Journal 124 (4): 528–533. doi:10.2307/1790942. JSTOR 1790942. 
  13. ^ a b Bisson, J. (2003). Mythes et réalités d'un désert convoité: le Sahara. L'Harmattan. (French)
  14. ^ a b Walton, K. (2007). The Arid Zones. Aldine. ASIN B008MR69VM. 
  15. ^ http://sundoc.bibliothek.uni-halle.de/diss-online/07/07H178/t3.pdf
  16. ^ http://books.google.fr/books?id=FqfnEQioIuEC&pg=PA84&lpg=PA84&dq=Southern+Libya+sunshine+duration&source=bl&ots=gDHZpxt-Ro&sig=Be8dwAsuzpSb0iGDqbsW4MxjsCw&hl=fr&sa=X&ei=pxtSU-CRMofaOOD5gJAL&ved=0CDUQ6AEwAA#v=onepage&q=Southern%20Libya%20sunshine%20duration&f=false
  17. ^ "Climate data for Wadi Halfa, Sudan"
  18. ^ http://www.seriousrankings.com/top-10-sunniest-places-in-the-world/
  19. ^ "Atar Climate and Weather Averages, Mauritania". Weather2Travel. Retrieved 2014-01-15. 
  20. ^ Cite error: The named reference Voodoo_Skies was invoked but never defined (see the help page).
  21. ^ "Weather Information for Asswan". Retrieved August 31, 2012. 
  22. ^ "Asswan, Egypt: Climate, Global Warming, and Daylight Charts and Data". Retrieved 20 June 2013. 
  23. ^ "Climate Statistics for Aswan, Egypt". Retrieved February 27, 2012. 
  24. ^ "Climate Normals for In Salah". Retrieved 31 May 2013. 
  25. ^ a b "In-Salah, Algeria". Climatebase.ru. Retrieved 31 May 2013. 
  26. ^ "World Weather Information Service – Khartoum". UN. Retrieved 6 May 2010. 
  27. ^ "Average Conditions Khartoum, Sudan". BBC Weather. Retrieved 21 August 2009. 
  28. ^ Climate Data. "Climate Bilma, Niger". Climate Data. Retrieved 2012-04-14. 
  29. ^ "Climate data for: Sebaa". climate-data.org. Retrieved 23 October 2013. 
  30. ^ "Taoudenni, Mali Weather Averages". Chinci World Atlas. Retrieved December 4, 2011. 
  31. ^ "Luxor, Egypt: Climate, Global Warming, and Daylight Charts and Data". Climate Charts. Retrieved 9 July 2013. 
  32. ^ "Luxor Climate and Weather Averages, Egypt". Weather2Travel. Retrieved 15 August 2013. 
  33. ^ a b "Weatherbase: Historical Weather for Abu Hamad, Sudan". Weatherbase. 2011.  Retrieved on November 24, 2011.
  34. ^ "Weather forecast for Timiaouine , Algerie: Climate". Storm247. Retrieved 3 August 2013. 
  35. ^ Climate Data. "Climate Agadez, Niger". Climate Data. Retrieved 2012-04-09. 
  36. ^ Climatological Information for Agadez, Niger, Hong Kong Observatory accessed 20 April 2012.
  37. ^ a b c Kevin White and David J. Mattingly (2006). Ancient Lakes of the Sahara 94 (1). American Scientist. pp. 58–65. 
  38. ^ a b Orbit: Earth's Extraordinary Journey documentary
  39. ^ Christopher Ehret. The Civilizations of Africa. University Press of Virginia, 2002.
  40. ^ Fezzan Project — Palaeoclimate and environment. Retrieved March 15, 2006.[dead link]
  41. ^ "Geophysical Research Letters" Simulation of an abrupt change in Saharan vegetation in the mid-Holocene - July 15, 1999
  42. ^ Kröpelin, Stefan; et al. (2008). "Climate-Driven Ecosystem Succession in the Sahara: The Past 6000 Years". Science 320 (5877): 765–768. doi:10.1126/science.1154913. PMID 18467583. 
  43. ^ Oxfam Cool Planet - the Sahara - access February 10, 2008
  44. ^ Tiempo Climate Newswatch: Climate Change and the Sahara
  45. ^ "Expansion and contraction of the Sahara Desert between 1980 and 1990| Science 253: 299-301". Ciesin.columbia.edu. 1991-07-19. Retrieved 2010-06-12. 
  46. ^ "Sahara Desert Greening Due to Climate Change?". News.nationalgeographic.com. Retrieved 2010-06-12. 
  47. ^ "Think It's Cold Here? It Snowed On Sahara!". New York Times. 19 February 1979. pp. D4. Retrieved 17 June 2010. 
  48. ^ "Snow Falls In The Sahara". The Spokesman-Review (Eastern Washington ed.) (Spokane, Washington: Cowles Publishing Company). 19 February 1979. p. 1. 
  49. ^ Messerli, B. (1973). "Problems of Vertical and Horizontal Arrangement in the High Mountains of the Extreme Arid Zone". Arctic and Alpine Research (Boulder, Colorado: University of Colorado) 5 (3): 139–147. JSTOR 1550163. 
  50. ^ Kendrew, Wilfrid George (1922). The Climates of the Continents. Oxford: Clarendon Press. p. 27. ISBN 978-1-4067-8172-4. 
  51. ^ Storm brings snow to Sahara Desert
  52. ^ "Atlantic coastal desert". Terrestrial Ecoregions. World Wildlife Fund. Retrieved December 29, 2007. 
  53. ^ "North Saharan steppe and woodlands". Terrestrial Ecoregions. World Wildlife Fund. Retrieved December 29, 2007. 
  54. ^ "South Saharan steppe and woodlands". Terrestrial Ecoregions. World Wildlife Fund. Retrieved December 29, 2007. .
  55. ^ "West Saharan montane xeric woodlands". Terrestrial Ecoregions. World Wildlife Fund. Retrieved December 29, 2007. 
  56. ^ "Tibesti-Jebel Uweinat montane xeric woodlands". Terrestrial Ecoregions. World Wildlife Fund. Retrieved December 29, 2007. 
  57. ^ "Saharan halophytics". Terrestrial Ecoregions. World Wildlife Fund. Retrieved December 29, 2007. 
  58. ^ Mares, Michael A., ed. (1999). Encyclopedia of Deserts. University of Oklahoma Press. p. 490. ISBN 978-0-8061-3146-7. 
  59. ^ Houérou, Henry N. (10 December 2008). Bioclimatology and Biogeography of Africa. Springer. p. 82. ISBN 978-3-540-85192-9. 
  60. ^ "Rare cheetah captured on camera". BBC News. 2009-02-24. Retrieved 2010-06-12. 
  61. ^ http://www.iucnredlist.org/apps/redlist/details/full/221/0 The IUCN Red List of Threatened Species: Acinonyx jubatus ssp. hecki
  62. ^ McNutt et al. (2008). Lycaon pictus. In: IUCN 2008. IUCN Red List of Threatened Species. Retrieved 06 May 2008.
  63. ^ Borrell, Brendan (2009-08-19). "Endangered in South Africa: Those Doggone Conservationists". Slate. 
  64. ^ "Desert-Adapted Crocs Found in Africa", National Geographic News, June 18, 2002
  65. ^ Wehner, R.; Marsh, A. C.; Wehner, S. (1992). "Desert ants on a thermal tightrope". Nature (Nature Publishing Group) 357 (6379): 586–7. Retrieved 14 March 2014. 
  66. ^ "History of Nubia". Anth.ucsb.edu. Retrieved 2010-06-12. 
  67. ^ PlanetQuest: The History of Astronomy - Retrieved on 2007-08-29
  68. ^ Late Neolithic megalithic structures at Nabta Playa - by Fred Wendorf (1998)
  69. ^ Fayum, Qarunian (Fayum B, about 6000–5000 BCE?), Digital Egypt.
  70. ^ Predynastic] (5,500–3,100 BCE), Tour Egypt].
  71. ^ Keys, David. 2004. Kingdom of the Sands. Archaeology. Volume 57 Number 2, March/April 2004. Abstract. Retrieved March 13, 2006.
  72. ^ Mattingly et al. 2003. Archaeology of Fazzan, Volume 1
  73. ^ Fage, J.D. A History of Africa. Routledge, 4th edition, 2001. pg. 256
  74. ^ Trans-Saharan Africa in World History, Ch. 6, Ralph Austin
  75. ^ "Wauthier Bréard 1933" (in French). Retrieved 2013-02-22. 
  76. ^ Wauthier, René. "Reconnaissance saharienne". French Cinema Archives (in french). Retrieved 22 February 2013. 

ReferencesEdit

  • Chris Scott. Sahara Overland. Trailblazer Guides, 2005.
  • Michael Brett and Elizabeth Frentess. The Berbers. Blackwell Publishers, 1996.
  • Charles-Andre Julien. History of North Africa: From the Arab Conquest to 1830. Praeger, 1970.
  • Abdallah Laroui. The History of the Maghrib: An Interpretive Essay. Princeton, 1977.
  • Hugh Kennedy. Muslim Spain and Portugal: A Political History of al-Andalus. Longman, 1996.
  • Richard W. Bulliet. The Camel and the Wheel. Harvard University Press, 1975. Republished with a new preface Columbia University Press, 1990.
  • Eamonn Gearon. The Sahara: A Cultural History. Signal Books, UK, 2011. Oxford University Press, USA, 2011.

External linksEdit

Coordinates: 23°04′47″N 12°36′44″E / 23.079732°N 12.612305°E / 23.079732; 12.612305

Last modified on 19 April 2014, at 07:34