Sahara – the largest hot desert on Earth
The Sahara desert is a desert that is associated primarily with a sea of sand, undulating sand dunes and very high temperatures. This is all true, although only in part, because this largest desert in the world (not counting the polar ones in the Arctic and Antarctica) offers much more attractions and is extremely diverse. It is also not entirely sandy. In fact, the Sahara is a dozen different deserts, each of them has a completely different character.
We can find here both dunes exceeding 180 meters (590 ft) in height, as well as amazing rock formations, gravel and rocky spaces reminiscent of a foreign planet, we will finally find the Nile, Lake Chad, an extinct volcano or mountain ranges.
The Sahara desert is so vast (it covers an area comparable to the United States) that within it we will encounter different climatic phenomena and vegetation. After all, the desert, which covers the area of as many as 11 countries, must impress and surprise.
From sea to desert
A few million years ago, no one would have recognized today’s Sahara because its land was under water and therefore was the seabed. As time passed, the water gradually subsided, revealing the land that was boiling with vegetation. There was a tropical forest, similar to the rainforests of South America. It was hot and humid.
So what happened that today it is impossible to look for even a periodic river in the Sahara?
The angle (precession of the Earth’s axis angle) of the globe is responsible for climate change in this part of the world (and not only there). As it changed, so did the climate. The Sahara Desert was gradually getting drier and hostile to living organisms.
60,000 years ago
Even 60,000 years ago, there were fertile fields, green valleys and plenty of permanent residents. 20,000 years later, the valley began to desert, although it remained fertile for a long time, full of vegetation and natural wealth.
8,000 years ago
Over 8,000 years ago, however, the heavy rainfall ended and a period of very long drought began, but many peoples still managed (they were mainly cattle breeders).
4,000 years ago
About 4,000 years ago, however, the climate in the Sahara desert turned into such a hell that life was only possible in oases.
In the future
Since changes in the tilt of the earth’s axis take place every 41,000 years (from 22° to 24.5°), in several thousand years (about 15,000 years), the desert may again resemble a green valley.
Today, the Sahara covers an area of over 9 million square kilometers, which is difficult to imagine. It is a huge and very diverse area. To the north, the Sahara is surrounded by the coast of the Mediterranean Sea, to the west by the Atlas Mountains and the Atlantic Ocean, and to the east by the Red Sea.
As you can see, the desert is surrounded by water on all sides and in really large amounts. This water, even in the form of clouds, almost never reaches the desert areas. The southern border of the desert is marked by rivers (including the Niger) and a transitional zone stretches: the desert slowly turns into a savannah, very dry at first, and the further south it is, the more green and irrigated it becomes.
Climate and shape
The Sahara desert is considered the hottest desert in the world. It has a tropical climate that is extremely dry. The average annual rainfall does not usually exceed 100 milliliters (and this is in mountain areas, as it rains even less often and less farther from them).
The closer to the center of the Sahara, the hotter and even extremely dry it gets, and more rainfall occurs at its ends – both north and south (here it can drop to 200 milliliters of water, so still very little). Hot, strong winds (mainly in the north), which can even turn into hurricanes, have a devastating effect on the entire Sahara. There are also sandstorms.
In the Sahara desert we can find all types of deserts:
- Rocky hamada (stone plateaus)
- Ergs (sand seas – large areas covered with sand dunes)
- Gravel plains (reg)
We can find here mountain ranges (including the Saharan Atlas, the Tibesti Mountains or the Red Hills of the Black Sea) and an extinct volcano, which is the highest point of the desert – Emi Koussi, which is almost 3.5 thousand meters high – exactly 3,415 meters (11,204 ft).
The Sahara desert is also about dune fields and sand seas, with which it is most associated, but also stone plateaus, gravel plains and dry lakes.
There are large fluctuations in temperature both throughout the day and throughout the year. They may not be as extreme as in the Gobi Desert, but they can still reach several dozen degrees of difference. Although there are no typical seasons in the Sahara desert, it is possible to clearly distinguish cool January (a dozen or so degrees) from hot July (forty degrees, and sometimes even more).
Apart from the only permanent rivers, which are the Nile and the Niger, only intermittent rivers and lakes can be found in the desert. Among these constants is the freshwater lake Chad, which was once an inland sea. There are numerous dry valleys (known as wadis), inselbergs and troughs where some water collects after rainfall.
Interestingly, the Sahara (as well as the Gobi Desert) has large clusters of shallow surface waters and artesian springs. Thanks to this, it is possible to create oases.
There are also rich resources of crude oil and natural gas (they are mainly mined by Algeria and Libya), and iron, copper, uranium and rock salt are mined here.
Eastern Desert and Libyan Desert
Among the many deserts of the Sahara, Eastern and Libya Deserts are the most famous and popular. The Eastern Desert is a popular tourist attraction that attracts thousands of visitors each year. It is situated east of the Nile and west of the Red Sea.
The Eastern Desert has nothing to do with the great sea of sand and dunes, with which the entire Sahara is most often identified. It is a rocky, sometimes more sand and gravel land with an extreme climate and moonlit views. It has an extremely dry, tropical climate with a total rainfall of less than 10 milliliters per year. It happens that it does not rain here for several years in a row. For this reason, there are many dry valleys and troughs of dry lakes in the Arabian desert. It was these areas that the Israelites made on their way to the Promised Land.
Libyan Desert (Western)
The Libyan Desert (the Egyptians call it the Western Desert) covers a huge area that stretches from eastern Libya to the Western Desert of Egypt and far northwestern Sudan. It is here that we find a sea of sand, amazing sand formations and high dunes. The dunes reach several hundred meters in height and are constantly wandering, pushed by tropical winds. The temperature in the Libyan desert exceeds 60 degrees Celsius (140℉), which makes it a real hell on earth. It hardly rains here. Annual rainfall does not reach even 10 milliliters.
Other interesting parts of the Sahara desert include the Ténéré area, which was once a seabed and then home to many dinosaurs whose bones are still found by scientists today. There were also wild tribes who left prehistoric ornaments and drawings on the rocks. Today it’s hard to even walk there, let alone live. It is a rocky desert in the northern part and a sandy one in the southern part, with shifting sands and shifting dunes. It’s so dry and hot that hardly any plant wants to sprout there.
The border of Algeria, in turn, is the area of the Tanezrouft desert. It is hardly raining here, daytime temperatures exceed 40 degrees, and at night they drop even below zero. In this stony-rocky land it is hard to endure, the area is completely barren and empty. An ancient trade route once led through this wilderness and is still used today.
Fauna and flora of the Sahara
Although life in the desert is not easy, many species of plants and animals somehow cope with such extreme conditions. Most of the plants can be found on the northern and southern edges, in the center of the Sahara, all life dies. The vegetation of the northern part of the Sahara is a bit like the Mediterranean, because oleanders, olives and pistachios grow here.
The southern part of the Sahara is an area of tamarisk and acacia. In the extreme conditions of the desert interior, plants in a residual form can be found in depressions, the bottoms of dry valleys, and also on rocks. There are xerothermic (adapted to hot dry environment) shrubs on the gravel areas, and some types of dune grasses and thorny thickets on the sands. In the Sahara desert there is also a Rose of Jericho, a strange plant rushing through the desert as a ball of dried up shoots that cover the infructescence. Date palms, cereals and tobacco are grown in the oases.
As for animals, the Sahara is inhabited by 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. Other animals: desert jerboa, camels, Barbary sheep, African donkeys, Nubian ibex, desert dragons, Egyptian Uromastyx, scorpions, Dorcas gazelles and scimitar-horned oryx. We can also meet jackals, hyenas, ostriches, vultures and even cheetahs (on the outskirts of Sahara).
The Sahara Desert in numbers
- The Sahara desert covers an area of 9,200,000 square kilometers (3,600,000 sq mi)
- Length: 4,800 km (3,000 mi)
- Width: 1,800 km 1,100 mi)
- The Sahara desert is located in as many as 11 African countries.
- About 4,000 years ago, the climate in the Sahara desert changed radically from a green land to a desert
- In many areas of the Sahara there is less than 10 milliliters of rain per year
- The dunes in the Sahara desert can exceed 300 meters in height and are constantly moving
- The temperature in the Libyan desert (which is part of the Sahara) sometimes exceeds 60 degrees Celsius (140℉).
The Sahara desert consists of 14 deserts:
- Al-Hamada al-Hamra
- Eastern Desert
- El Djouf
- Erg Chech
- Erg Ikidi
- Grand Erg Occidental
- Grand Erg Oriental
- Hoggar Mountains
- Libyan Desert
- Tibesti Mountains
Sahara – interesting facts
- The word Sahara in Arabic means just desert (sometimes the term “the Greatest Desert” is used).
- There are more than 20 lakes in the Sahara desert, but almost all of them are saltwater. The exception is Lake Chad, where the water is sweet.
- The Sahara, like the Gobi Desert, is constantly expanding its territory, which is associated with desertification and drainage of areas on the outskirts of the Sahara.