Sahara Desert

Sahara Desert Africa

Sahara desert image courtesy: z.about.com

The cradle of human evolution

The largest desert in the world that occupies half the area of the Great African Continent, in area it equals the US and larger than continent of Australia. In fact size is not the only thing that makes Sahara a great place in the world. Its richness in history and culture defeats any other places on earth whether fertile or desert. Numerous cultures and ancient cities flourished in these desert areas. It had been the cradle where human beings got evolved from humanoids to hunters and gatherers before becoming farmers.

Four zones

Sahara desert map courtesy: geology.com

Sahara Desert occupies 9 million sq km (half of the Continent of Africa); the whole area are not covered by sand dunes as general concept; it is heterogeneous in topography; can be classified in to four sections, erg is sand dunes area also called sand sea, hamada is stone plateau; characterized by bare rocks, wadi is a dry valley with thorny bushes here and there, Shatt is salt flats with salt marshes.

Sahara’s eastern border is marked by Red Sea and Egypt; west is bound by the Atlantic Ocean; Atlas Mountain and the Mediterranean Sea comes at the north; south is Sudan and the Valley of River Niger.

Not just sand dunes and rocks

Cairo; the capital of Egypt and its everlasting Pyramids, numerous structures, the mummies, Timbuktu; home of the Sankore University in Mali; the center of ancient wisdom, Abu Simbel the temple of Ramesses II near Aswan in Egypt all these flourished in this desert.

Once upon a time

Sahara was not so millenniums back (BC 12,500 to BC 3500 known as the African Pluvial Period), it was as fertile as other parts of Africa, but as years passed Sahara became arid due to many reasons no theory stands beyond dispute. The most popular theory is the El Nino-Southern Oscillation Cycle that led to sudden drying of the place there by pushing its inhabitants to the Mediterranean and beyond.

One strange theory cites poor lambs as the villains of this tragic story; excessive grazing led to the loss of vegetation causing warming up of the land and eventual destruction of the area.

Stake holders

Sahara desert image courtesy: danheller.com

The whole area of Sahara is shared by many nations like Mauritania, Western Sahara, Morocco, Algeria, Tunisia, Libya, Egypt, Sudan, Chad, Niger and Mali. While Egypt is blessed with River Nile other nations live enduring scarcity of water. About half of Sahara Desert receives about 2 cm or less of rain while rest receives about 10cm.

The Sahel and dust devil

This desert has one of the harshest climates in the world; it has two distinct zones one the northern Sub Saharan Africa and the southern the semi arid savanna called the Sahel. ‘Sand storms’ are regular visitors of this area which are strong enough to carry mountains of sand from one place to the other; another phenomenon called the ‘dust devil’ is like a tornado when dust and sand stand vertically like a spinning pillar.

Significant names and places

The Atlas Mountain, It is a 2400 km long mountain range (it has five distinct portions Middle Atlas, High Atlas, Anti Atlas, Tell Atlas and the Sahara Atlas) that forms the northwest frontier of Sahara; passes through Morocco, Algeria and Tunisia; highest peak Jbel Toubkal (height 4167 meters); inhabited by Berber Tribes in its Morocco portion and Kabyle Tribes in Algeria.

Berbers are primitive tribes of Africa (the word was derived from Roman word barbarian), they live scattered in the desert nations; now they are slowly getting assimilated in to the Arab customs, at present due to mixing they have become different groups like Taureg, Kabyle, Heratin, Shluh etc.

Kabyles are an offshoot of the Berber Tribes live in mountainous region of Algeria who speaks Berber Language. They bravely fought against the Algerian government which banned Berber language and jailed their activists. This revolution is known as the ‘Berber Spring’ (Tafaut meaning spring in Kabyle); Algerian government brutally suppressed the movement; leaving Kabyles live with wounded psyche.

Tibesti Mountains is a mountainous region in the Central Sahara in Northern Chad extending to northeast Niger. Its highest peak the Emi Koussi is 3415 meters high. The significance of this area is that it has markings of an ancient river that existed millenniums back; more over the rocks have figures of crocodiles indicating presence of water animals.

River Nile, The longest river in the world with a length of 6650 km (one recent opinion places River Amazon as the longest); the life blood of Sahara (irrigates 3.4 million sq km); it has two tributaries; the White Nile and Blue Nile. The Whit Nile starts from The Great Lakes area of southern Rwanda and flows north touching, Tanzania, Lake Victoria, Uganda, and Sudan, while the Blue Nile starts from Lake Tana in Ethiopia and enters Sudan; where at Khartoum both meet together to form the Nile which falls in to the Mediterranean. It is on the banks of Nile; the whole Egyptian culture developed giving birth to all the monuments like the Pyramids, great temples like Abu Simbel and Karnak, numerous palaces, sculptures etc.

Lake Chad is one of the largest water bodies of Africa at the southern end of Sahara; it is the main source of water to Chad, Niger, Nigeria and Cameroon. Satellite imaging has illustrated that this lake is shrinking in size due to diversion of water to irrigation. Climate change in the area has also contributed to the shrinkage. The present area is only 5% of the size to that about 35 years back (at that time it equaled Great Lake Erie in area).

Terkezi Oasis in the Sahara Desert image courtesy: nasa.gov

Niger River, The third longest river in Africa (length 4180 km), its role in irrigating the arid region of Saharan Africa (2.1 million sq km) is second only to Nile. Niger has its origin in Guinea treads away from the sea as it has a mission to irrigate Sahara; passes through Mali, Niger and enters in to Nigeria after sharing some water to Benin. The course is in the shape of a boomerang with Timbuktu as the turning point. Before falling in to the Gulf of Guinea it gives birth to the Niger Delta (with marshes, lakes and numerous streams) almost the size of Belgium.

Qattara Depression, it is a desert basin in Libya; below 130 meters below sea-level; the second lowest point in Africa; area 18,000 sq km comprising of saline marshes, playas (dried up lake floors) that occasionally flood, steep cliffs, and the Fech-fech (a quick-sand like land with finely powdered sand which act as a trap to vehicles and people). The Qattara Depression is home to many animals and plants. There is proposal to let in sea-water to this depression and generate electricity exploiting the level difference of 130 meters. Such a project is under study for the Dead Sea by Israel.

Sand dunes and ergs; while sand dunes in deserts are massive pile of sand; the ergs are sand dunes those are actively getting shifted to places by desert-wind. They are formed on bed of former lakes and are extremely difficult to cross.

Oasis Crater in Libya is mark of a meteor hit that took place in the Sahara 120 million years back. Time has had its effect on the crater as it stands much eroded yet clearly visible. Satellite images have shown that there are three concentric rings to the crater; outer, middle and the inner; the rocks are sand stone Crustaceous era. Its outer ring 18 km in diameter it is discontinuous and attains up to 30 meters in some places.

The Kabira is yet another meteorite crater northeast to Oasis crater recently discovered by NASA. It has an outer ring far bigger (31 km in radius) than that of Oasis; as per scientists the meteorite that struck here must be of 1.2 km in diameter.

Waw an Namus (old name Uau an Numas) volcano, Libya, It is often described as ‘an exotic volcano’ due its golden yellow desert sand surroundings and the stark black ring of volcanic ash deposited in the ‘caldera’ (a large crater formed due to the collapse of a former volcano) and the present cinder cone that is 120 meter high. This site is at 1200 meters above sea level. This volcano is active but recently no lave flow has been reported.

The Red Sea forms the northeastern border of the Sahara Desert; this straight is an inlet of the Indian Ocean passing through the arid deserts. The Red Sea divides two large continents; Asia and Africa; the Northern Red Sea is a large biosphere and home to a large variety of corals and fish.

The real wealth of Sahara

Sahara desert image courtesy: photos-of-the-year.com

Sahara; generally written off as an arid desert hold in its laps many of the gems that adds beauty and variety to the world. The real value of Sahara is the abundant sunlight that profusely showers trillions of units of power on its desert sand. It is high time the world to recognize the value of this non depleting source of power. Instead of running after polluting petrol ‘air car’, biodiesel and jatropha; if anything done to tap the energy that goes wasted on the 9 million sq km area the world will never face anything like ‘energy crises’ or ‘oil-shock’.