Of all the deserts we have written or will write in coming days, Sahara Desert is one of the most fascinating ones out there. Why so? Because it swings between sand and greenery in a fixed cycle. Yes, it simply means, that a time comes when it changes from barren sand ocean to a patch of land full of greenery. And… it then, once again, becomes sandy! Sounds weird, right? So, here you go – 70 Sahara Desert facts that you should learn and know. It is fascinating, we promise!
Sahara Desert Facts: 1-5
1. Sahara Desert is the world’s largest hot desert. But of all the deserts in the world, it ranks third in terms of area. It comes after Antarctica and Arctic deserts. The Antarctica and Arctic deserts are cold deserts.
2. The word Sahara is derived from the Arabic word ‘ṣaḥra’ meaning desert. It includes most of the North Africa (leaving the coastal side of the Mediterranean Sea, Maghreb’s Atlas Mountains and Nile Valley present in Sudan and Egypt).
3. Mediterranean Sea is towards the north of the desert, the Red Sea towards its east side, Atlantic Ocean towards west and Sahel (a biogeographical transition zone between desert and savanna, a type of grassland) towards its south.
4. There are many divisions of Sahara Desert. They are: Western Sahara, Libyan Desert, Aïr Mountains, Tibesti Mountains and Ahaggar Mountains.
5. From thousands of years, Sahara has been switching from a desert to a savanna and then back to a desert. This is cyclical and happens every 41,000 years. The next time Sahara will turn into a savanna is after 15,000 years from now i.e., in 17,000 CE.
Sahara Desert Facts: 6-10
6. 31% of Africa is covered by Sahara Desert. Vast areas of countries like Libya, Algeria, Niger, Chad, Egypt, Mali, Western Sahara, Tunisia, Sudan and Mauritania make up the Sahara Desert.
7. Area of this desert is 3,500,000 square miles or 9 million square kilometers. If those areas which receive precipitation below 250 millimeters are included then, the area increases to 4,200,000 square miles or 11 million square kilometers.
8. Sahara mostly consists of hamada (land area which has hard rocky plateaus). Ergs (flat lands covered by sand) form a small part of the desert.
9. Richat Structure or the Eye of Sahara in Mauritania is a rare type of landscape in the desert. Many mountains (mostly volcanic) are present in Africa. Examples will be Tibesti Mountains, Ahaggar Mountains, Red Sea hills etc.
10. Emi Koussi (a volcanic mountain in Tibesti range, height of 11,204 feet or 3,415 meters) is the highest peak in the Sahara Desert. It is present in the Northern Chad.
Sahara Desert Facts: 11-15
11. The northern and southern ends of the desert have certain amount of grasslands and receive little rainfall but the central Sahara is extremely dry. Sometimes this area experiences no precipitation for years. It is in this central Sahara that you can find Libyan Desert, Tanezrouft, Nubian Desert etc.
12. North Sahara experiences Mediterranean climate because Mediterranean Sea borders north side of Sahara. To understand the northern limit of the desert, two types of plants are observed – one is date palms and the other is esparto (grass characteristic of the Mediterranean Sea). The northern limit of date palms and southern limit of esparto tells you about the northern limit of the Sahara.
13. The northern limit of Cenchrus biflorus (grass characteristic of Sahel) and Cornulaca monacantha’s (a flowering plant species) southern limit marks the southern boundary of this desert. The southern boundary usually receives 150 millimeters rainfall.
14. Major cities in Sahara Desert are Nouakchott, Tamanrasset, Ghardaia, El Oued, Ghat etc.
15. This desert is present between the horse latitudes (a belt of high atmospheric pressure present between 30 degrees North and 30 degrees South, also known as Hadley Cell).
Sahara Desert Facts: 16-20
16. Between the horse latitudes, warm and high pressure upper tropospheric air descends causing drying effect in the upper part of the troposphere. This descending air stops any evaporated water to travel upwards and hence the cloud formation doesn’t usually take place.
17. The weather is mostly sunny (because of nearly zero clouds) and dry. There is very little to no rainfall.
18. Libyan Desert is the sunniest and driest part of the entire Sahara Desert because of the descending tropospheric air. Rainfall is also extremely scanty in this area compared to the other areas of the desert.
19. Eastern part of Sahara is drier and sunnier than the western part. But, high pressure is not the only culprit here. The Atlas Mountains (spread across Morocco, Tunisia and Algeria) act as barriers and cause a rain shadow (as the mountains act as barriers for clouds, one side of the mountain receives rain and the other side remains dry and the side which remains dry is called rain shadow).
20. Intertropical Convergence Zone is the major source of rain for this desert. This zone brings irregular rains to Southern Sahara and Sahel regions.
Sahara Desert Facts: 21-25
21. Climate of Sahara Desert can be summed up as: extremely high temperatures and highest ever potent evaporation (potential evaporation is the evaporation that would have occurred if there was enough water in that area), very long duration of sunshine, unreliable and low rainfall, prominent diurnal temperature variation (high variation of low and high temperature occurring on same day).
22. Sunshine duration is very high in Sahara. Most parts of the desert experience nearly 3,600 hours of sunlight or sunshine yearly which would make up 82% of the time. Some parts of the eastern side of the desert receives 4,000+ hours of sunshine a year which makes up 91% of the time.
23. Constant sunlight, low humidity, very less rainfall, no vegetation etc. make Sahara Desert the hottest continuous area of the world and some parts of the desert are hottest places on Earth during the summers.
24. The average temperature of the desert is nearly 25 to 30 degrees Celsius. Average high temperature is more than 40 degrees Celsius which can go on for months at a stretch.
25. The areas which have mountains have little less temperature than the rest of the parts of Sahara Desert. Highest average temperature ever recorded was 47 degrees Celsius in Bou Bernous (a town in Algerian Desert).
Sahara Desert Facts: 26-30
26. Ground and sand temperatures are even higher. During day, temperature of the sand is nearly 80 degrees Celsius and ground temperature is nearly 72 degrees Celsius.
27. During the nights temperatures usually fall anywhere between 13 to 20 degrees Celsius. Coastal areas are colder than inland areas. During winters, temperature can go below 0 degrees Celsius at night.
28. Northern and southern parts of Sahara Desert receive between 100 to 250 millimeters of rainfall because of low-pressure systems near Mediterranean Sea and Intertropical Convergence Zone respectively. Morocco, Algeria etc. fall under the northern part whereas Niger, Mali etc. belong to southern part of the desert.
29. The central and eastern part remain completely unaffected by these two low-pressure systems and can even receive less than 1 millimeter of rainfall a year. In fact, most parts of the Sahara Desert receive less than 20 millimeters of rainfall a year.
30. 31% of the total area of Sahara (1,100,000 square miles or 2,800,000 square kilometers) receives nearly 10 millimeters of rainfall.
Sahara Desert Facts: 31-35
31. 17% of the total area (580,000 square miles or 1,500,000 square kilometers) receive almost 5 millimeters of rainfall.
32. For an area of 390,000 square miles or 1,000,000 square kilometers, there is virtually no rainfall at all! This area is present in eastern part and consists of Egypt, Sudan and Libya.
33. Potential evaporation is extremely high. It ranges from 2,500 millimeters to 6,000 millimeters per year.
34. There are two records of snowfall in Ain Sefra town in the Sahara Desert – one in February 1979 and the other in December 2016.
35. Because of changes in the North African Monsoon caused by the North African Climate Cycle, Sahara changes from desert to savanna and then back to a desert. It takes 41,000 years for this transition to happen.
Sahara Desert Facts: 36-40
36. The Sahara that we see today is the dry or “desert Sahara” (because of weak North African Monsoon). In 15,000 years from now, there will be “green Sahara” (because of strong North African Monsoon). But what causes this?
37. It is said that the changes in the orbit of earth causes changes in the insolation (incoming solar radiation), which in turn controls the monsoon patterns all over the world. This theory was first proposed by Rudolf Spitaler in 1800s.
38. The theory was tested by John Kutzbach, a meteorologist in 1981. The results are widely accepted today. Ruddiman gave this hypothesis the name – ‘Orbital Monsoon Hypothesis’.
39. The growth of speleothems was observed in Ashalim, Ktora Cracks, Hol-Zakh, etc. Speleothems require rainwater to grow and are helpful in knowing whether an area had received rainfall during a particular period or not.
40. Growth of speleothems and other climatic conditions like sudden movement of Inter-Tropical Convergence Zone and changes in El Niño-Southern Oscillation Cycle are strong evidences for the continuous cycle that Sahara goes through (that is desert to savanna and then back to desert).
Sahara Desert Facts: 41-45
41. There are 8 ecoregions in Sahara Desert because there are variations in rainfall, temperature, soil, elevation etc. These 8 ecoregions are mentioned below.
42. Atlantic Coastal Desert – It is a very thin strip present along the coast of Atlantic Ocean. It has an area of 15,400 square miles or 39,900 square kilometers. This ecoregion is present to the south of Mauritania and Morocco. Because of the Canary Current, lichens, shrubs and succulents grow in this region.
43. North Saharan Steppe and Woodlands – It is towards the northern side of the desert and next to the woodlands, Mediterranean forests etc. It has an area of 646,840 square miles or 1,675, 300 square kilometers. It is present in Egypt, Morocco, Algeria etc. Shrubs and dry woodlands grow in the north because of the rains during winter. South side is completely dry.
44. Sahara Desert Ecoregion – The extremely dry central part falls under this zone. It has an area of 1,791,500 square miles or 4,639,900 square kilometers. It includes Egypt, Algeria, Libya, Mali, Chad etc. There is no proper vegetation and the land is covered by hamadas, sand dunes etc.
45. South Saharan Steppe and Woodlands – It is present from east to west across the continent as a narrow strip. It is present between hyper-arid central part of Sahara Desert and Sahel. It covers an area of 425,400 square miles or 1,101,700 square kilometers. Algeria, Sudan, Mali, Chad etc. fall under this ecoregion. Because of the summer rains during the month of July (caused by the of the influence of Intertropical Convergence Zone) grasses, dry woodlands, herbs etc. are seen in this region.
Sahara Desert Facts: 46-50
46. West Saharan Montane Xeric Woodlands – This ecoregion is characterized by the presence of volcanic highlands. Woodlands and shrubs are seen because of the moist and cool environment (caused by the volcanic highlands). It has an area of 99,650 square miles or 258,100 square kilometers.
47. Tibesti-Jebel Uweinat Montane Xeric Woodlands – This ecoregion consists of Jebel Uweinat and Tibesti highlands. It covers an area of 31,700 square miles or 82,200 square kilometers. Parts of Chad, Libya, Egypt, Sudan etc. come under this ecoregion. Because of highland and a bit more rainfall, woodlands and shrubs are seen here. Some of the plants are oleander, dates, tamarix, acacia etc.
48. Saharan Halophytics – It consists of saline depressions with the presence of halophytic plants (plants adapted to the highly saline conditions). It covers an area of 21,000 square miles or 54,000 square kilometers. Parts of Egypt, Tunisia, Algeria etc. fall under this ecoregion.
49. Tanezrouft – This ecoregion is the harshest, driest and hottest part of the desert and also one of the hottest, driest places of the world. There is no vegetation at all. This zone borders Algeria, Mali, Niger.
50. There are a total of 2800 vascular plant species found in Sahara. One-fourth of them are endemic (seen in a particular place and nowhere else). Nearly half of them are seen in Arabian Desert as well. 500 species of plants are seen in the central Saharan region. These plants include palms, succulents, spiny shrubs, acacia etc.
Sahara Desert Facts: 51-55
51. Plants have adapted themselves according to the harsh climate of the Sahara Desert. Their leaves are modified as spines, they have succulent or fleshy stems, well developed root system which spreads across a large area to trap water.
52. Animals found in Sahara include many species of fox (pale fox, fennec fox etc.), addax (a white antelope which can live without drinking water for a year and it is the largest indigenous mammal of Sahara), gazelle (rhim gazelle or dorcas gazelle), cheetah, sand vipers, monitor lizards, red-necked ostrich, hyrax and African wild dog, deathstalker scorpion, desert crocodiles, Saharan silver ant etc. Dromedary camels and goats are domesticated.
53. Did you know the Saharan silver ants come out of their nests for just 10 minutes every day? They do so for the extreme high temperatures outside and also to avoid predators.
54. Many thousand years ago, Sahara was more or less a wet place. There are petroglyphs (images made on a big rock by chipping off small pieces) of crocodiles. Fossils of many animals were also found in Sahara. Afrovenator is one such example.
55. Kiffian culture lived in the Sahara during the Neolithic Subpluvial. It was a phase in North Africa’s climate history when it was wet and rainy. However, period before and after the Neolithic Subpluvial were way drier. Neolithic Subpluvial is also known as Holocene Wet Phase.
Sahara Desert Facts: 56-60
56. Kiffians lived some 10,000 to 8,000 years ago (during Neolithic Subpluvial). Some 8,000 years ago, Sahara became completely dry. This wiped out the Kiffians. Their remains have been found in Gobero in Niger (in year 2000), which is the earliest and largest grave in the desert.
57. In the same site of Gobero, archeologists also found the fossils or remains of Tenerians. They were the middle Holocene culture. Their graves had artifacts which suggested that they observed spiritual traditions. Triple burial of a mother and two children was also excavated. Tenerian culture came some 1,000 years after the Kiffians were wiped out.
58. Nubians settled in an area which is presently Sudan. They were Neolithic people but they practiced agriculture and had settled lifestyle.
59. Predynastic Egyptians lived in Egypt’s Southwestern corner at around 6000 BCE and were advanced than the earlier communities. They practiced agriculture, used tools made of metals, made pottery etc.
60. By 3,400 BCE Sahara became as dry as we know it today. This happened because Earth’s orbit shifted. The aridification resulted in nearly zero penetration by humans. Whatever settlements remained usually concentrated around many oases that dotted the landscape.
Sahara Desert Facts: 61-65
61. Interiors of Sahara didn’t see any trade after 3,400 BCE. However, trade continued in Nile Valley. Nile however had several cataracts (shallow lengths where rocks and boulders jutted out of the river bed. This made contact and trade by boat extremely difficult.
62. Phoenicians lived around 1200 to 800 BCE. They had confederation of kingdoms across Sahara to Egypt. They are predecessors of the people who speak Berber language.
63. At around 500 BCE, Greeks traders started trading along the desert’s eastern coast. Many urban civilizations like Garamantes rose around the same time and that too at the very heart of Sahara.
64. Byzantine Empire’s entry in Africa marked the spread of Islam in the entire Sahara. With this, slave trade picked up pace. The empire ruled from 5th to 7th Ottoman empire then emerged as the ruler of entire Sahara. Islam’s influence continued in Africa.
65. Then came the Europeans in 19th Many countries like France, Spain, Italy etc. had colonies there.
Sahara Desert Facts: 66-70
66. In 20th century, each country started getting independent from the countries which colonized them. Some of the countries participated in WWII as well.
67. Many different groups of people of different origins live in Africa. Some of them are Toubou, Nubians, Kanuri, Songhai, Beja, Zaghawa, Fula etc. Arabian dialects are used by most of the groups.
68. There are several languages spoken in Sahara. However, Arabic dialects are the most widely spoken ones.
69. Arabic, Beja and Berber (as well as variants of Berber) are the languages that belong to Hamito-Semitic or Afro-Asiatic family.
70. Did you know that Sahara consists of 70% gravel and 30% sand?