Sahara Desert – interesting facts. Great Sahara Desert

Great Sahara Desert is located in North Africa and partially or completely covers the territory of almost eleven countries. This is the largest desert in the world, covering an area of ​​more than 9,000,000 square meters. km, quite comparable to the area of ​​the United States. It extends 1600 km wide and about 5000 km long from east to west. They say that a thousand years ago the climate in the desert was more humid. The fact is that in the distant past, the territory of the Sahara underwent various atmospheric changes, which led to a change in climatic conditions. The desert divides the African continent into two parts - North and Sub-Saharan Africa. By reading the interesting facts below, you will learn more about this desert.

The Sahara Desert is the second largest desert in the world (after Antactis) and the largest hot desert on the planet.

It covers almost all parts North Africa. Extends from the Red Sea, including sections Mediterranean coast, to the outskirts Atlantic Ocean. In the southern region, its border is the semi-arid savannah region of the Sahel, separating the desert from Sub-Saharan Africa. However, the boundaries of the desert are not clearly defined, moreover, beyond last thousand over the years they have undergone significant changes.

The Sahara passes through the following countries: Algeria, Chad, Egypt, Libya, Morocco, Mauritania, Mali, Niger, Sudan, Tunisia, Western Sahara.

The history of the desert goes back at least 3 million years.

The climate of the Sahara is combined: in the north it is subtropical, and in the south it is tropical.

The relief is quite varied, but in general it is a plateau lying at an altitude of 400-500 m above sea level. There are underground rivers here, which sometimes flow to the surface, forming oases. Vegetation develops well in such natural oases. The soil in these regions of the Sahara is very fertile, so where irrigation is possible, excellent crops grow.

Part of the desert territory is occupied by sand dunes that reach a height of 180 meters .

The central region is more elevated above sea level compared to the rest of its regions. The central plateau stretches for 1600 km from northwest to southeast. Its height ranges from 600 to 750 m, some peaks reach a level of 1800 m and even 3400 m. The highest points are the peaks of Emi Koussi with a height of 3415 m, Tahat - 3003 m, the Tibetsi massif and Ahaggar Highlands.

This may seem strange, but in winter on mountain peaks there are snow caps. In the eastern part of the Sahara - the Libyan Desert - the climate is the driest, so there are very few oases here. This part contains sandy areas with large dunes, the height of which reaches 122 meters or more.

The climate of the Sahara Desert is very hot and dry. It gets very hot here during the day and cool at night.

The Sahara region receives only 20 cm of precipitation per year. It is for this reason that a very small population lives here, only 2 million people.

The desert used to be fertile land where elephants, giraffes and other animals grazed. Gradually it became increasingly arid, and the fertile landscape turned into the barren region we know it today.

The central part of the Sahara is extremely dry, with sparse or no vegetation. In areas where moisture accumulates, grasslands, desert shrubs, trees and tall shrubs are sometimes found here.

During the last Ice Age, the desert was larger than it is now, extending south beyond its present boundaries.

The climatic conditions here are considered the most severe in the world. Prevailing northeasterly winds often cause sandstorms and micro-tornadoes called “dust devils.”

Arabic is the most widely spoken language in the Sahara, from the Atlantic to the Red Sea.

The Sahara is divided into several regions: Western Sahara, Central Highlands of Ahaggar, Tibesti Mountains, Aïr Mountains (region of desert mountains and high plateaus), Tenere Desert and Libyan Desert (driest region).

The Nile River Valley and the mountainous regions of the Nubian Desert east of the Nile are geographically part of the Sahara Desert. However water of the Nile turned this territory

Sahara Desert on a map of Africa
(pictures are clickable)

The Sahara Desert is located in North Africa, covers about a quarter of the continent and is the largest tropical desert on the planet. Geographically it covers the southern regions of Morocco and Tunisia, most of Egypt, Algeria, Mauritania and Libya, the northern territories of Mali, Niger, Chad and Sudan. The maximum length from the northern tip to the southern is about 2000 km, and from the western to the eastern - 5700 km. Since the boundaries of the Sahara are defined differently by individual researchers, estimates of the area vary - from 6 to 8 million km².

Climate in the Sahara Desert

Climatic conditions are characterized by high air temperatures with very large daily and annual fluctuations. Daytime temperatures in some areas rise to 56-58 °C, thereby approaching the maximum on the planet. At night, on the contrary, frosts on the soil are common. In the central mountain ranges Night temperatures down to -18 °C are recorded. Sandstorms that do not subside for several days and wind speeds during which reach 50 m/sec are very common.

The average annual precipitation in the outlying areas is 100-200 mm, on the plains less than 50 mm (in the mountains, as a rule, less than 100 mm). In the central part of the desert, rain may not be seen for several seasons in a row.

But one can also observe a situation when, at the last exodus of strength, rolling from one dune to another, as a certain gift from higher powers, a green oasis with palm trees and murmuring water appears on the horizon. It is he who constantly reminds us that the desert is alive, which means it is capable of surprising its visitors again and again.

Flora and fauna

Sahara Desert photo

The vegetation for the most part is perennial grasses and shrubs, resistant to drought and having a fairly deep root system (reaching 15-20 m), as well as ephemeral plants, the period of development of which occurs after rainfall. In general, the vegetation cover is quite sparse, and in places where sand accumulates it is completely absent. Mountainous areas boast a wide variety of vegetation, where many endemic plants can be found. Of the trees and shrubs, the most common are some types of acacias, tamarisks, ephedra, and gorse.

The fauna in the driest areas is very poor (with the exception of birds, about half of whose species are in Sahara Desert migratory). There are a total of about 60 species of mammals, including the Saharan hare, several species of gazelles and the most adapted ungulate for long-term existence without water - the Mendes antelope. Among the predators you can find the fennec fox, jackal, cheetah, and hyena. From the rodent family, gerbils and jerboas are common. A large number of reptiles: lizards, monitor lizards and snakes.

Real life in the desert begins at night. The sunset gives a signal to animals that they can leave their daytime shelters and begin an active search for food, as well as enjoy the fresh wind and coolness.

Sahara Desert photo

The population of the Sahara, not including densely populated areas in the valley and the Nile Delta, is about 3 million people. Two thirds of the population (the density is 1000 people per km² or more) is concentrated mainly in the northern part of the Algerian Sahara, along the outskirts of the western and southern regions, as well as in oases. Ethnic composition very variegated with a predominance of the Berber-Arab population. The Ahaggar Highlands and the Air Plateau are home to the Tuaregs (nomadic pastoralists), whose number is about 30 thousand people. The Tibesti Highlands are the habitat of the Negroid Tubu tribe.

The traditional occupations of the local population are nomadic animal husbandry and collection of wild edible plants and fruits. Agriculture is widespread in Voasis, where date palm crops and vegetables are grown. Nomadic and semi-nomadic tribes are engaged in breeding camels, sheep and goats. With the onset of spring, they move in search of pastures for them, and winter in oases.

Overall, the Sahara Desert is a unique phenomenon created by nature. Nothing shakes the human consciousness more than hot “red” sands, black rocks and majestic sand dunes.

Where is the Sahara Desert located?

The Sahara Desert is the largest SANDY desert on our planet and it is located in the northern part of the continent of Africa. She also takes second place as the most big desert in the world in area, giving way to the Antarctic desert. The area of ​​the Sahara covers about 8.6 million km2 and partially occupies the territory of 10 states. From west to east its length is 4800 m, and from south to north its length ranges from 800 to 1200 meters. Moreover, the size of the desert is not constant; it grows annually by 6-10 km from south to north.

Sahara desert landscape

The landscape of the Sahara consists of 70% plains and 30% of the Tibesti and Ahaggar highlands, the stepped plateaus of Adrar-Iforas, Air, Ennedi, Tademait, etc., as well as cuesta ridges.

Sahara desert climate

The desert climate is divided into subtropical in the north and tropical in the south of the desert. In the northern part of the desert there are large temperature fluctuations, both average annual and average daily. In winter, temperatures in the mountains can drop to -18 degrees. Summer, on the other hand, is very hot. The soil can warm up to 70-80 degrees Celsius.

In the southern part of the desert, temperature fluctuations are slightly less, but also in winter, temperatures in the mountains can drop below zero degrees Celsius. Winters are milder and drier.

The desert is characterized by large temperature fluctuations between night and day. This figure is expressed by up to 30-40 degrees difference between night and day temperatures! Therefore, sometimes you can’t do without warm clothes there at night, as the temperature can drop below zero. Also in the desert there are often sandstorms, in which winds can reach up to 50 meters per second. Central parts of the desert may not see rain for years, and other parts may even experience heavy downpours. In other words, the Sahara Desert is full of surprises when it comes to weather.

Sahara Desert - amazing place. It is incredible how animals, plants, and people were able to adapt to life in this part of the earth, given the constant drought and heat.

1) The size of the desert is as big as half of Russia, or the whole of Brazil!
The Sahara Desert is the largest desert in the world, covering 30% of Africa. But this is half Russian Federation, or the entire area of ​​Brazil, which is the fifth largest country on Earth.

2) “A sea without water.” In Arabic, the Sahara is a desert, and some people called it the “Sea without Water” because once upon a time there were many rivers and lakes in its place.

3) Mars on Earth. Desert dunes move from a couple of centimeters to hundreds of meters per year, and the dunes themselves resemble the landscapes of Mars! Sometimes they reach a height of 300 meters!

4) There are fewer and fewer oases. Villages and towns usually appear near oases, but every year there are fewer and fewer oases.

5) The average temperature in the desert is about 40 degrees Celsius! The sand itself heats up to 80 degrees Celsius! But at night the temperature can drop to -15 degrees Celsius.

6) Over the past fifty years, storms have begun to appear more and more often, in some places their occurrence has increased forty times!

7) 3 million people live in the Sahara. However, there used to be more people; once upon a time, caravans of traders passed through the desert, carrying various riches. But crossing the entire desert took 1.5 years!

8) The roots of some plants are at a depth of 20 meters! In this way, plants try to get water for themselves in order to retain it for a long time and use it carefully.

9) There are about 4 thousand different species of animals and plants in the Sahara.

10) Camels live without water for 14 days, and without food for as many as 30! They can smell moisture from 50 kilometers away, and drink one hundred liters of water at a time! And they don't sweat at all! Their humps are fat, thanks to which they can survive for a long time without food.

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Once upon a time, herds of elephants roamed the tropical forests and leopards hunted. A dense network of rivers and lakes covered the steppes, and caravans loaded with gold, slaves and ostrich feathers crossed the sands. And all on the same territory! Sahara Desert occupied a third of Africa, almost its entire north. The area of ​​the Sahara is only slightly smaller than the United States; it now comfortably accommodates a dozen countries. But there are half as many residents here as in St. Petersburg.

On maps, the Sahara Desert is depicted as a huge yellow spot, and this is probably why most people imagine it as a boring plain with endless sands. In fact, the Saharan landscapes are surprisingly diverse. Here stretch mountains, tracts of bushes, rubble and gravel, steppes and scorched clay plains. There are oases where life is in full swing, and around there are dry river valleys, salt marshes and lakes scattered huge stones and rocky hills. And, of course, sand, from which the wind forms bizarre reliefs - labyrinths, undulating fields and dunes as high as a 60-story (!) skyscraper. Here you can hear “singing sands”: moving, dry hot grains of sand create sounds reminiscent of squeaking, grinding, rattling, grumbling of a dog, a vibrating hum that can be heard 10 km away.

"Sugar Pump"

The climate of the Sahara is controlled by an invisible conductor - the wind. Above the equator, the air becomes very hot, rises and moves towards the poles. Along the way, it cools, descends in the northern Sahara and returns to the equator, replacing heated, rising portions of air. This pattern is called the “Saharan pump”, and the air currents that constantly rush from the tropics to the equator are called trade winds.

Flying over the north of the continent, the dry trade wind carries away the remaining moisture from the surface of water bodies and land. Already at a speed of 10 m/s, it even pulls it out of the soil, and plant roots are deprived of nutrition. And when the wind gets stronger, it carries away the fertile soil itself. In addition to the trade winds, local winds blow here - khamsin, ghibli, sirocco. They carry sand and heat to the north, to Spain and Italy, at hurricane speeds (up to 40 m/s). When there is no wind, “dry fogs”—fine dust—hang over the Sahara.

Climate of the Sahara.

In the Sahara, summer temperatures around +50°C are common. You can fry eggs on stones and sand without lighting a fire. The heat of the day gives way to night cold (up to +15°C). Rocks burst from such changes!

In the hot air, mirages are frequent - imaginary reflections of what lies beyond the horizon. Since stable caravan routes have developed in the Sahara, mirages are often visible in the same places. Maps have even been drawn up, where the places where 1,500 mirages appear are indicated, and conventional icons show what can be seen where: an oasis, the ruins of a fortress, a well, mountains, etc.

Receiving excess solar heat, the Sahara languishes from moisture deficiency. In many regions, rain has been expected for years. Sometimes its drops do not reach the ground, drying up on the way.

Snow happens in the Sahara, but it is always a world sensation. This happened in 2016, and before that in 1979!

Through the sands, rainwater easily seeps underground, and over millions of years, real fresh lakes. In some places, underground water is being squeezed closer to the surface. In such places, oases have long been formed - with drinking springs, palm trees, etc.

The Sahara has the driest air in the world. Clouds in the local sky are rare guests. For this reason, the heat is even greater, and Eastern Sahara is one of the most illuminated places in the world. Here the Sun shines on average 11 hours every day throughout the year.

How did the Sahara Desert appear?

Millions of years ago, the land from Spain to Mongolia was flooded by the Tethys Ocean. Whales frolicked in it, dinosaurs roamed along the shores. Then, when they began to rise from the depths mountain systems, the ocean was receding. Its remains formed the Mediterranean, Black, Sea of ​​Azov, Caspian and Aral. And the current Sahara is the former bottom of Tethys. It is not surprising that skeletons of extinct animals have long been found in the desert from Morocco to Egypt. For example, 45-ton paralititans, Egyptosaurs and other monsters.

About 9,000 years ago, the local coastal forests were replaced by African steppes - savannas: deep rivers and lakes, a carpet of dense grasses, and woodlands. Herds of giraffes, elephants, antelopes, buffalos, rhinoceroses, flocks of ostriches and lions roam around. People quickly developed the fertile region - they hunted, fished, raised livestock, and settled along the rivers. On the rocks, now lost in the sands, entire galleries of graffiti were discovered - images and inscriptions that confirm this. Why is it not like this now? There is no unity among scientists here. Some people explain everything by the arrival of aliens. But there are also more realistic assumptions.

Hypothesis 1. The climate has become “not the same”. It was once hotter and sea levels were higher. The air above the equator heated up more, which means it retained heat longer and cooled further than it does now over the Mediterranean Sea. Having descended, the trade winds were saturated with its moisture, rushed towards Africa and brought rain and fog. They created the prosperity of the Sahara.

Hypothesis 2. The earth swayed in the wrong direction. As the Earth moves around the Sun, the tilt of its axis is not constant. As a result, the planet receives different amounts of solar heat and light, and the seasons alternate. Over thousands of years, this inclination and the orbit itself change noticeably. Therefore, global climate change is coming. It is possible that the enormous drought in northern Africa is just such a case.

Hypothesis 3."Global flood". Fossilized bones of whales, sharks, rays, turtles, and mollusk shells are found shallow in the Sahara. But the ocean existed for millions of years; kilometer-long layers of marine sediments must have lay above the bones. Where are they? It is possible that they were carried away by a real flood, the legends of which are preserved in the Bible and folklore. Streams of ocean water washed away the top layer of soil and brought the remains of animals. The root cause of the flood could have been the fall of a huge meteorite, which caused a tsunami and turned mountain ranges into dust and sand.

Hypothesis 4. With my own hands. Perhaps the formation of the Sahara is the first ecological catastrophy in the history of mankind. The nomadic way of life does not focus on caring for the preservation and restoration of the natural environment. A nomad - he is here today, there tomorrow. Together with their herds, which eat and trample down the greenery. Devoid of a network of roots, the soil is easily blown out and washed away. The bare soil and the air above it warm up more, a zone of high pressure arises, and the winds blow not here, but from here, not allowing clouds to come close.

Most likely, the Sahara arose under the influence of several natural factors, which were aggravated by human irrationality. And even now... Construction of highways, exploration and production of oil and gas, car rallies - all this destroys the fragile ecosystems of the desert.

Sahara Desert. Plants. Country of dates and fennecs.

Our ancestors came up with the word “desert” to designate the property of the vast landscape that struck them - its “emptiness,” that is, uninhabitation. Living here permanently is, indeed, almost impossible. But there are extreme sports among both plants and animals.

For plants, the Sahara could become a paradise - a lot of light, heat, mineral salts. But without water, you understand... Nevertheless, about 3,000 species of plants were discovered in the desert, and every fourth cannot be found outside of it. Many species live only where there is water, in oases - with date palms, cypress trees, vegetables, citrus fruits, pomegranates, and cereals. And in those that grow outside oases, botanists have identified a lot of adaptations that allow them to overcome moisture deficiency:

• a dense and extensive network of surface roots - allows you to effectively absorb moisture from rare rains, morning fogs and dew before everything dries out;
• deep (up to 30 m!) roots - reach groundwater, penetrate through cracks into the thickness of rocks;
• the leaves are narrow, small, covered with hairs (wormwood), wax, turned into spines (cacti) or scales (saxaul) - in order to evaporate less moisture;
• thickening of stems and leaves, which turn into fleshy storehouses of water (aloe);
• storing reserves of moisture and nutrients underground - in rhizomes, bulbs, tubers;
• the roots are covered with a thick bark or case of congealed juice and sand and do not dry out when the wind blows the soil off them;
• the stem grows very quickly and/or roots grow in any place – protection from being covered with sand;
• a very short period of life - sometimes in a few spring days the plants manage to bloom and form seeds, and then they lie and wait (sometimes for years) until “life gets better”;
• development of salt marshes - here moisture and salts are constantly drawn up from the depths through the capillaries of the soil;
• They can withstand almost complete drying out, but recover very quickly after rains.

Sahara Desert and fauna.

Desert animals also have to deal with the problem of water shortage. Some hide during the day and are active during the cooler hours, from dusk to dawn. Thicker body coverings protect against moisture loss from scorpions and beetles. There are many species that can go a long time (or even never) without drinking - they only need the meager moisture that is always available in their food.

Reptiles feel quite good in the Sahara - cobras, vipers, chameleons and others. Densely covered with scales, they are protected from moisture loss. The skink lizard can literally “swim” in the sand: immediately diving into it, it rows with its legs and makes its way through the sand at a speed of up to 90 cm per minute.

Many prefer to live not among clay and rubble, but in the sand, where it is easier to burrow, make underground holes and wait out the heat there (jerboas and other small rodents). Sahara's calling card could be a funny fennec fox - smaller than our usual cat, but with huge ears. Ears allow excess heat to be released more quickly (protection against overheating). And, of course, together with their big eyes, they help hunt for mice and beetles at night. The smallest animal of the cat family, the sand cat, also lives in the Sahara. There are also antelopes - gazelles, and monitor lizards similar to small crocodiles.

You won’t believe it, but…toads also live here. And not off the banks of the Nile, but in Central Sahara. They sleep, buried deep in the clay soil, eat nothing and barely breathe, but as soon as there is a good rain, every large puddle is swarming with toads. They lay eggs, the tadpoles develop rapidly, and when the puddle dries up, a new generation of toads settles down underground. Desert snails can remain in underground hibernation for more than one year.

The Sahara is home to some of the most heat-resistant animals - satin runner ants. They are active at air temperatures up to +70°C. Their long legs allow them to hold their bodies high above the hot soil. Their body is covered on top with silvery hairs that reflect sunlight. And the hairs on the bottom, like radiator plates, remove excess heat from the body. Runners emerge from their burrows to the surface when their enemies, the lizards, are hiding from the heat. Insects scurry around, collecting food for 10 minutes, and then go underground too - it gets hot for them too.

And for humans, the most important desert animals have been camels for centuries. True, there have been no wild ones in the Sahara for a long time, but caravans of domesticated camels leisurely cross it constantly.

The Sahara Desert is turning... Transforming...

In the 19th and 20th centuries, Europe hatched plans to change the Saharan climate and restore the lost prosperity of these lands. For example, it has been proposed more than once to create a “Sahara Sea”: to build a canal that would connect the Mediterranean Sea with relief depressions in the north of the desert. They say that the man-made reservoir will increase the humidity of the air, and the trade winds will carry this moisture, pouring rain over the desert. The project “didn’t work” - calculations showed that the lowlands are small, most of the desert lies above sea level, so it will not be possible to create a stable reservoir.

In 2008, the Sahara Forest project was born. British engineers proposed not just greening the desert, but installing powerful solar power plants and a network of greenhouses between the forest plantations. sea ​​water. According to the plan, at the stations, circular mirrors will collect sunlight and use it to heat water in a boiler, the steam of which will turn the turbines. They will provide energy for desalination plants, and fresh water will go to greenhouses. And the population will receive water for drinking and irrigation, electricity and agricultural products. The project has attracted interest in the Middle East, in the Arabian Emirates, but the political situation in North Africa does not yet give hope for the transformation of the Sahara.

The same can be said about the “Great Man-Made River” project, which Libya undertook to implement: supplying underground fresh water through a network of pipes covering almost the entire country. Water came to cities and villages, in the south, in the desert, groves of date palms, gardens and fields turned green, but all work was interrupted Civil War (2011–2014).

Meanwhile, the Sahara continued its advance, moving inexorably towards the equator. Back in 1974, the Green Wall program started working in Algeria. Here they began to plant strips of trees along roads and oases. Eucalyptus and pine trees formed a belt 1,500 km long. It kept the soil from weathering and reduced the speed of dry winds. The expansion of the Sahara in this area has slowed down.

Assessing this success, the African Union took up the Great Green Wall project in 2010. In fact, it is an expanded continuation of the Algerian program. Across the entire continent, from Somalia to Senegal, planting of a continuous green ribbon 15 km wide and 7,775 km long has begun. Of course, huge costs. Of course, there are no guarantees that what was planted will take root, that local residents they will not cut down trees for firewood, etc. But something needs to be done!

Meanwhile, satellite images (2002) showed that in the west the Sahara Desert began to retreat. Thick grass returns to the pastures, acacias are growing, ostriches and antelopes have appeared. Environmentalists do not rule out that this is the result - oddly enough - of global warming. The warmer the air, the more water vapor it can hold. As a result, the winds bring heavier and more frequent rains. Whether the trend will continue is unknown. Sahara Desert After all, she is also famous for her ability to present surprises.

About ten thousand years ago, the area where the largest desert on our planet, the Sahara, is now located, was covered with grass, low shrubs and was densely populated. After our planet slightly changed the tilt of its axis, the climate began to gradually change, it became hot, the rains stopped - and many representatives of the animal world left the resulting desert.

The Sahara (translated from Arabic as “desert”) is the most large desert of our planet, which is located in northern Africa and is located on the territory of ten countries. On geographical map it can be found at the following coordinates: 23° 4′ 47.03″ N. latitude, 12° 36′ 44.3″ e. d.

The Sahara occupies about thirty percent of the African continent, and its area is about 9 million km2:

• From east to west, the length of the desert is 4800 km: the Sahara begins on the coast of the Atlantic Ocean and ends on the coast of the Red Sea.
• The length of the Sahara from south to north ranges from 800 to 1200 km. The desert begins in the north of the continent near the coast of the Mediterranean Sea and the Atlas Mountains, southern border limited to 16° N. sh., in an area of ​​sedentary ancient dunes, to the south of which begins the tropical savanna Sahel, a transitional area between the desert and the fertile soils of Sudan.

When exactly the Sahara Desert was formed on the territory of the African continent, scientists do not have a consensus: earlier its age was estimated at 5.5 thousand years, then at four, recently they began to be inclined to think that it was even younger, and its lands only became deserted near three thousand years ago.

The desert is located in the northwest of the stable ancient African plate, so ground shaking is rarely observed today. In the center of the platform, the relief rises from west to east: some of the largest high-mountain regions of the desert are the Ahaggar and Tibesti plateaus, where, unlike the rest of the Sahara, snow falls briefly almost every year.

From the northern and southern parts of the uplifts there are deflections of the platform, where in former times there was a sea, and therefore the soil is characterized by the presence of marine sedimentary rocks. In the south of the desert, the trough of the platform led to the formation of large lakes, which are the main suppliers of fresh water in their region. First of all, we are talking about Lake Chad and the Ounianga group of lakes.

Sands occupy only a quarter of the Sahara, while the thickness of the sand layer is about 150 meters. Rocky soil predominates: it occupies about 70% of the desert area, the remaining part is volcanic mountains, as well as pebble and sandy-pebble soil.

There are also many aquifers (sedimentary rocks with varying degrees of permeability, the cracks and voids of which are filled with water), which are the main suppliers of water to the oases.

Sometimes in the desert there are also fertile lands - mainly near oases that take water from underground rivers and reservoirs, the water of which, due to its own pressure, was able to reach the earth.

On the map of Africa, the Sahara is divided into several regions:

• Western Sahara - located in northwestern Africa, the territory is characterized by coastal lowlands that turn into elevated basement plains and plateaus.
• The central highlands of Ahaggar - on the map are located in the south of Algeria, the highest point is Mount Takhat with a height of 2918 meters, so snow often falls here in winter.
• The Tibesti mountain plateau is located in the center of the desert, in the north of the state of Chad and partly in the south of Libya. Highest point The plateau is the Emi-Kusi volcano, almost 3.5 km high, on the top of which snow falls annually.
• The Tenere Desert is located in the south-central Sahara. It is a sandy plain with an area of ​​about 400 thousand km2, which is located in the northeastern part of Niger and western Chad.
• Libyan Desert - on the map of Africa it is located in the north and is the driest region of the desert.

Climate

The Sahara is the hottest and hottest place on our planet: even the driest desert in the world, the Atacama, which is located in South America, cannot compare with it.

The weather here in summer is extremely hot: air temperatures at this time often exceed 57°C, and the sands heat up to 80°C. At the same time, the Sahara Desert is one of the few places on our planet where evaporation significantly exceeds the amount of precipitation (with the exception of narrow coastal strips). While the average precipitation is only 100 mm (and there may not be any in the center for several years in a row), 2 to 5 thousand mm of moisture evaporates.

Conventionally, Sugar can be divided into two climatic zones, northern (subtropical) and southern (tropical):

The northern part of the desert is characterized by hot summers (up to 58°C) and cold winters (especially cold weather in the mountains, where temperatures can drop to -18°C). The annual precipitation rate is 80 mm, rainy weather here from December to March and in August, with thunderstorms and even severe short-term floods not uncommon. In winter, snow falls briefly on the high plateaus of Ahaggar and Tibesti almost every year.

The south is characterized by mild winters, and at the end of the hot and dry period it rains. In mountainous regions there is little precipitation, and it occurs evenly throughout the year. In the lowlands, rain falls in the summer, often accompanied by thunderstorms; about 130 mm of precipitation falls per year. In the west, near the Atlantic coast, the humidity is higher than in the rest of the Sahara, and there are often fogs here.

The difference between day and night air temperatures in the Sahara is often about forty degrees: average temperature in the center of the desert in July it is 35 °C, while at night the air temperature drops to +10 or +15 °C. The weather here is warm even in winter: the temperature of the coldest month of the year is +10°C (therefore, snow is an extremely rare phenomenon).

The climate of the Sahara is greatly influenced by constantly blowing strong winds, especially in the north of the desert (only 20 days a year are windless). The winds blow mainly from north to east: the movement of humid air masses Mediterranean air stops mountain range Atlas Mountains

As for the air currents that move from the south, when they reach the central part of the desert, they manage to lose moisture. Therefore, the winds in the northern part of the desert have especially destructive power. They move at a speed of about 50 m/s and, raising dust, sand, and small stones to a height of more than a thousand meters, cause tornadoes and severe sandstorms, often moving dunes.

Water resources

The only river in North Africa that passes through eastern part Sugars towards Mediterranean Sea is the Nile, whose length is 6852 km (the river is the second longest after the Amazon, and flows through South America).

Since as we move through the desert, a considerable part of the water evaporates, an important role is played by its two tributaries, the White and Blue Nile, which flow into it in the southeast of the desert (they are very clearly visible on the map). In the 60s of the last century, the Nasser reservoir was created between Egypt and Sudan, the total area of ​​which exceeds 5 thousand km2.

In the south of the Sahara, several river streams flow into Lake Chad, whose area ranges from 27 to 50 thousand km2 (depending on precipitation in the region), after which part of the water leaves the lake - and the water continues to flow in a northeast direction, replenishing watersheds.

In the southwest the Niger River flows into the Gulf of Guinea of ​​the Atlantic Ocean. This river is interesting because, starting almost near the ocean, 240 km from the coast, it flows in the opposite direction, into the Sahara, after which it turns sharply to the right and continues its path in a southeast direction (the shape of the river, if you look at a map of Africa, resembles a boomerang).

IN northern part In the desert, water comes from streams of wadis, temporary water streams that appear after rainfalls and flow down from the mountains. Wadis also feed the desert soil in its central part. A lot of rainwater is found in the dunes: once in the sand, the water seeps down the slopes and flows down.

Under the desert sands there are huge pools of groundwater, thanks to which oases are formed (there are especially many of them in the north of the Sahara, while in the south the aquifers are located deeper).

Another source of water in the largest desert on the planet is the relict lakes (remnants of former seas) located on the outskirts and in the mountain ranges, often swampy and salty, although fresh ones are often found among them (for example, the water of most lakes of the Unianga group).

Flora

There is little vegetation in the Sahara - mainly shrubs, herbs and trees that grow near natural bodies of water, along wadis or in high-altitude regions, including olives, cypress, dates, thyme, and citrus fruits.

In areas where there is little water supply, only those types of vegetation are found that tolerate drought well. In rocky areas and places where sand accumulates, there are no plants at all.

Fauna

The desert is home to almost 4 thousand representatives of the animal world, most of which are invertebrates. Animals of the Sahara Desert live mainly near water (they are practically not found in arid areas) and are nocturnal.

Most of the animals are monitor lizards, cobras, lizards, chameleons, and snails. The reservoirs are inhabited by crocodiles, frogs, and crustaceans. There are about sixty species of mammals, including cheetah, spotted hyena, sand fox, and mongoose.

About 300 species of birds live in the Sahara, 50% of them are migratory. These are primarily ostriches, African eagle owls, fantailed and desert crows and others.

Desert and people

Despite its huge area, the desert is sparsely inhabited: only 2.5 million people live here. Some peoples lead a nomadic lifestyle, but most prefer to settle down. People settle only near oases, as well as in the valleys of the Nile and Niger rivers, where there is enough water and vegetation to survive and feed livestock. At the same time, cattle breeding: goats and sheep predominates over fishing and hunting.