Where is the Red Sea located on the map. Red Sea Great Blue Hole, Belize

Having a natural origin and characterized by a constant directional flow. It can start from a spring, a small pond, a lake, a swamp or a melting glacier. It usually ends by flowing into another larger body of water.

The source and mouth of a river are its essential components. The place where it ends its path is usually easy to see, and the beginning is often determined only conditionally. Depending on the terrain and the type of reservoirs into which rivers flow, their mouths may have differences and characteristic features.

Terminology

From source to mouth, the river flows in a channel - a depression in the earth's surface. It is washed away by a stream of water. The mouth of a river is its end, and the source is its beginning. The land surface along the flow has a downward slope. This area is defined as a river valley or basin. They are separated from each other by watersheds - hills. During floods, water spreads into depressions - floodplains.

All rivers are divided into lowland and mountain. The former are characterized by a wide channel with a slow flow, while the latter are characterized by a narrower channel with a fast water flow. In addition to the primary source, rivers are fed by precipitation, groundwater and melt water, and other smaller streams. They form tributaries. They are divided into right and left, determined along the flow. All streams that collect water in a valley from source to mouth form a river system.

In line they distinguish deep places(reaches), holes in them (pools) and shallows (rifts). The banks (right and left) limit the water flow. If during floods the river finds a shorter path, then in the same place an oxbow lake or a secondary channel (branch) ending in a dead end is formed, which connects downstream with the main stream.

Mountain rivers often form waterfalls. These are ledges with a sharp difference in height of the earth's surface. In valleys near rivers with wide channels, islands can form - parts of land with or without vegetation.

Source

Finding the beginning of a river can sometimes be difficult. Especially if it flows in a swampy area and takes water from many of the same type of fickle streams or springs. In this case, the beginning should be taken as the area where the current forms a permanent channel.

It is easier to determine the origin of a river if it starts from a pond, lake or glacier. Sometimes two independent large water streams, which have their own names, join together and then have one channel throughout. The neoplasm has its own name, but the point of confluence cannot be considered the source.

The Katun River, for example, connects with the Biya, which is similar in size. For both, the point of confluence will be their mouths. From this place the river already bears a new name - Ob. However, its source will be considered to be the place where the longer of these two tributaries originates. The confluence of the Argun and Shilka rivers seems to give rise to the Amur, but to say that this is its source is incorrect. At this point, two rivers merge to form a new name (toponym).

Estuary

All rivers flow into a larger body of water. The places where they merge are easily determined. This could be a larger river, lake, reservoir, sea or ocean. For each case, the mouth will have its own characteristics.

In rare cases, the mouth of a river is where it ends, spreading over the surface without any new formation. Often the earth's surface in such areas has a minimal or reverse slope. In this case, the water slows down, seeps into the soil or evaporates (dry mouth). It also happens that its demand in certain regions is excessively high. Water is withdrawn for irrigation, drinking or other needs.

Taking this into account, an estuary is a section of a river where it flows into another larger body of water, ends up drying up naturally, or is used for consumer needs.

In addition to the usual confluence of rivers, deltas and estuaries are distinguished separately. They differ in the degree of manifestation of sedimentary rocks at the junction of the riverbed and the reservoir. Deltas are characteristic of rivers flowing into lakes, reservoirs and closed seas of continental type. They are formed by several branches and ducts.

On the coasts of oceans and open seas, the river is affected by ebbs and flows. Streams of salt water prevent silt deposits from being deposited, the depth remains constant, and wide estuaries are formed.

At the mouths of rivers there is often a long bay - a lip. It is a continuation of the channel, stretches to the very point of confluence and has a large width. The estuary, unlike the bay, is also a bay, but shallower due to the deposited silt deposits. It is often separated from the sea by a narrow strip of land. Formed due to flooding of low-lying coastal areas.

Delta

The name comes from the time of the historian Herodotus. Seeing the branched mouth of the Nile River, he called it a delta, since the outline of the area resembled the letter of the same name. This type of river mouth is a triangular formation consisting of several branches branching from the main channel.

It is formed in areas where a large amount of sediment is transported downstream by river flow. At the confluence, the flow slows down and particles of silt, sand, small gravel and other debris settle to the bottom of the riverbed. Gradually its level rises and islands form.

The water flow is looking for new passage ways. The river level rises, it overflows its banks, flooding and developing adjacent areas with the formation of new branches, channels and islands. The process of settling of transported particles continues in a new place - the mouth continues to expand.

There are active deltas characterized by abundant sedimentary processes. They are formed under the influence of counter flows of fresh and sea water. Internal deltas, in fact, are not such and can be located far from the mouth upstream of the river. They also have branching branches and ducts, but they then merge into a single channel.

Estuary

If a river carries an insufficient amount of sediment into the sea or ocean, a delta does not form at its mouth. The influence of ebb and flow of tides also does not contribute to this. In the open seas and oceans where rivers flow, salt water entering their mouths forms a powerful flow and wave, which in some cases can go several kilometers deep, changing the direction of the main current. During low tides, the backflow of heavy seawater removes all sediment particles.

An estuary is a greatly expanded mouth of a river. Unlike the delta, it has an ever-increasing depth and a pronounced wedge-shaped shape. The stronger the impact of the tidal wave on the banks of the river, the more distinct the outlines of the estuary.

A group of 5 karst lakes in the Chereksky district of Kabardino-Balkaria is located approximately 30 km south of Nalchik.

The lowest lake of this group is the most unique with a relatively small surface of 235 by 130 meters, its depth reaches 258 meters, and water saturated with hydrogen sulfide gives the lake a rich blue color.

The surface water temperature in winter and summer is about +9 degrees. This attracts divers from all over the world - a modern diving center has been built on the shores of the Lower Lake, which operates both in summer and winter.

Not a single stream or river flows into the lake, but about 70 million liters of water flow out every day. The lake level remains unchanged, which is explained by powerful underwater sources.

The nature here is quite picturesque: green hills, dense beech forests on steep slopes, and in the distance, in the blue haze, peaks sparkling in the sun.

2. Lake Khanka

Lake Khanka is located on the border of the Primorsky Territory of Russia and the Heilongjiang Province of China.

This is the largest freshwater body of water in the Far East. Area 4070 km² (at average water level), length 95 km.

24 rivers flow into the lake, and the Sungacha River flows into it.

The international Russian-Chinese Khanka Nature Reserve has been organized on the lake.

Due to its location, it attracts a large number of tourists who can get acquainted with the culture and customs of two countries at once. About 75 species of fish live in the waters of this lake, and even some of them are listed in the Red Book of Russia.

3. Seliger

Seliger is a system of lakes of glacial origin in the Tver and Novgorod regions of Russia. This lake is also called Ostashkovskoye, after the name of the city of Ostashkov, located on the lake shore.

The area of ​​the lake is 260 km². The area of ​​the entire basin is 2275 km².

Seliger receives 110 tributaries, and only one river, Selizharovka, flows out of it.

4. Topozero

Topozero is a crystal clear, deserted lake-sea, one of the largest lakes in Karelia.

It has an area of ​​986 sq. km, a length of 75.3 km, a width of 30.3 km, 144 islands with a total area of ​​63 sq. km. Topozero is part of the Kum reservoir system.

The rivers flowing into Topozero are Kizreka, Valazreka, Taka, the rivers flowing out are Pongoma, which flows into the White Sea, and Sofyanga, which flows into Pyaozero.

The nature and landscapes of Topozero are very beautiful. In the wide part of the lake, the opposite shores and chains of islands are hidden behind the horizon, the shores of the lake are often clad in steep rocky embankments, but there are also real harbors with sandy beaches protected by rocks. You can see extensive sandy and rocky shallows and swamps. There are a lot of berries in the swamps and forests: cloudberries, blueberries, blueberries, lingonberries.

Topozero keeps the secrets of history. Once upon a time, hermit monks lived on Zhiloi Island, spreading the Old Believer faith among the residents of villages on the shores of the lake.

The lake is ideal for sailing and kayaking routes. Numerous islands offer tired travelers overnight stops.

Fishing on Topozero is interesting and varied. The long rocky shallows are interesting for those who like to catch grayling; in the bays and lambins there are perch, roach and pike.

5. Raspberry Lake

One of most beautiful places Siberia is Raspberry Lake, Altai Territory. The reservoir is the largest bitter-salty lake among the Borovye lakes in this region. Its area is 11.4 square kilometers. Raspberry Lake may surprise you with the unusual color of its water. The reason for this is a branchial crustacean called Artemia salina, which lives in it. It produces a pink pigment that, when released into water, colors it. The color changes throughout the year. In spring it is the brightest and most saturated, and in autumn it turns brown. Since ancient times, the crustacean has been considered a food product, but today the crustacean is used only to feed fish fry.

Foreigners who were lucky enough to share a meal with the Great Empress Catherine II were surprised by the unusual pinkish-raspberry salt served to the table. They had never seen such a curiosity anywhere else. And the Russians knew that it was being brought from the far, far away Kulunda steppe, located at the foot of the Altai Mountains. But few could visit those distant places - it was so difficult to get there. There were only legends that there was a huge pink lake splashing there, and after swimming in it, motherless women soon gave birth to babies, and the pockmarked ones became prettier. And in the modern world, getting to those regions costs nothing, so many of our compatriots know for sure about the healing salty waters of Raspberry Lake. It really helps improve women’s health, has a beneficial effect on the skin (rejuvenates and cleanses it), relieves fatigue and muscle pain, treats inflammation, and swimming in the waters of this lake is a pleasure. There are also very beautiful landscapes here, so it’s an excellent place to relax and very popular among Siberians. However, tourists also come here from the European part of the country.

Water of a mesmerizing azure color, with a visibility of several tens of meters - some bodies of water on the planet are still distinguished by incredible environmental indicators. They miraculously managed to escape the harmful influence of civilization; for thousands and millions of years, the water in them remains crystal clear. Some of the cleanest lakes and rivers on the planet are located in incredibly inaccessible places; to see them, tourists need to overcome a difficult path. Others, on the contrary, have long been centers of tourist life, which does not prevent them from maintaining their unique environmental indicators. All the cleanest bodies of water on the planet are incredibly beautiful and certainly deserve the attention of the most sophisticated travelers.
Crater Lake, USA

In the USA, in the state of Oregon, there is an incredibly beautiful Lake Crater, it was formed in the crater of an extinct volcano. This lake has become famous throughout the world for its unique deep blue water, which is considered one of the cleanest in the world. According to scientists, this lake was formed more than 7.5 thousand years ago, its average depth is about 350 meters. The size of the lake is also quite impressive, its length is about 9.6 km and its width is about 8 km.

This lake is one of the deepest not only in the United States, but also in the territory North America. Several years ago, a national park was formed around a unique lake, on the territory of which today they conduct interesting excursions. The main event for travelers remains the climb to the crater of an extinct volcano; this is the only way to see the beautiful lake with your own eyes. In recent years, the amazing nature reserve has been visited annually by about 400,000 tourists from all over the world.

The crystal clear lake attracts not only curious travelers, but also ecologists and researchers. Several years ago, a group of scientists conducted an interesting experiment here. The fact is that initially there were no species of fish in Lake Kreiter; environmentalists decided to introduce some species of trout and salmon here. Their experiment was a complete success; today the lake is inhabited by fish. Tourists are even allowed to fish here, subject to the only condition - they must use artificial bait.

Lake Zyuratkul, Russia


In Russia, among the Ural Mountains there is an amazing lake Zyuratkul, it is located at an altitude of 724 meters above sea level and is the highest mountain lake in the Urals. The maximum depth of this lake is relatively small and is about 12 meters, and the area of ​​the reservoir is 13.5 square meters. km. Today, the amazing lake is considered one of the cleanest in the world, despite the fact that the water in it is by no means transparent. It has a cloudy tea color, which is explained by the fact that many streams flowing into the lake originate in swamps.

The area near the lake is famous not only for its natural beauty, but also for its historical sites. During the study, scientists discovered several important archaeological sites; here they raised tools of primitive people and found a giant geoglyph. For local residents, Lake Zyuratkul has been a sacred landmark for hundreds of years; many interesting legends and beliefs are associated with it.

In the forests located along the shores of the lake, hundreds of years ago the Old Believers performed their rituals; while walking through them, today you can see unusual monuments carved from wood. Excellent conditions for recreation have been created on the territory of the Zyuratkul National Park. There are several equipped camping areas, so during the warm season, travelers can stay in these picturesque places for several days. There are hundreds of different excursions here, during which you can see the most significant natural attractions, as well as unique historical areas.

Piccaninny Ponds, Australia


In Australia, on the territory of the Piccaninny Nature Reserve, there is a system of ponds of the same name, which have recently been considered a favorite vacation spot for divers. There are three ponds in the system, all of them are crystal different clean water. However, each of these ponds has its own unique characteristics. The “First Pond” is the smallest, its depth is only 10 meters. The “Abyss” pond is much deeper; its maximum depth is 100 meters. The water in this pond is crystal clear and visibility can reach 40 meters.

The Cathedral is considered the most unusual and interesting of the three ponds; its depth is 35 meters. This pond was formed in a grotto of limestone formation and is the most popular among divers. The system of ponds is located in a special swampy area, which is notable not only for its reservoirs, but also for its unique vegetation and fauna. This marshy area is home to several rare species of birds, the observation of which attracts not only ornithologists, but also tourists.

Piccaninny Park has many hiking trails for tourists, as well as several excellent viewing platforms from which you can admire the beautiful ponds and surrounding landscapes. Piccaninny National Park was established in 1969 and covers an area of ​​about 8.6 square kilometers. km. Since several years ago the ponds were opened to snorkeling and diving enthusiasts, today environmentalists monitor their cleanliness with particular care. Those who want to swim in these pristine ponds will need to comply with some formalities.

Lake Masyuko, Japan


In Japan, on the territory of the island of Hokkaido, there is another crystal clear lake - Masyuko. It is located in the Akan Nature Reserve, the lake is surrounded on all sides by incredibly beautiful mountain ranges covered with dense vegetation. This crystal clear lake was formed in a caldera active volcano, the water in it has a shade of rich blue color due to its special mineral composition. Hundreds of tourists visit this beautiful lake every day as part of organized excursions around the national reserve.

While walking through the mountainous areas, they will have the opportunity to see many rare plants, animals and birds; it is most interesting to walk through these colorful places in the summer. However, visiting the reserve in winter also has its charms. On the territory of the national park there is another crater lake, Kussyaro, which also has its own unique features. The thing is that several hot springs flow into it, which prevent some areas of the lake from freezing even in winter. This feature attracts many heat-loving birds to the reservoir; whooper swans always spend the winter here.

The main feature of Lake Masyuko is that not a single stream flows into it, nor does it flow out. Researchers believe that it is precisely this feature of the lake that allows it to maintain its crystal purity for hundreds of years. It is also worth noting that on the territory of the reserve there are several interesting miniature villages, where you can get acquainted with the life of local residents and buy interesting souvenirs.

Bowman Lake, USA


In the United States there is the amazing Lake Bowman, which is also famous for its clear water. It is located in Montana, on the territory national reserve Glacier. Despite the fact that the reserve is rich in a variety of natural attractions, it is still visited by very few tourists. This greatly contributes to the preservation of the unique ecosystem here. Lake Bowman is impressive in size: its length is about 11 km and its width is about 1.5 km.

This fabulously beautiful lake is considered one of the most transparent in the world; today tourists here are provided with all the conditions for organizing an interesting holiday. They can not only walk around the reserve, but also spend several days in a tent camp. The lake is home to a lot of fish, which tourists are allowed to catch, and you can also swim in some areas of the lake.

The tent camp located on the shore of the lake is open only in the warm season and is well equipped. Toilets and even showers are equipped on its territory; every measure is taken here to preserve the ecology of these places. Today, the main guests of this “resort” are local residents, although in recent years Bowman Lake has also attracted a fair number of foreign travelers. Getting to this wonderful lake is not difficult; there is a road through part of the reserve.

Lake Sheosar, Pakistan


In the northern part of Pakistan, in the territory of the Deosai National Park, there is a fabulously beautiful Lake Sheosar. It has gained popularity among tourists precisely because of its crystal clear water. For hundreds of years, this lake has remained one of the cleanest bodies of water on the planet. The maximum depth of this lake is 40 meters, its length reaches 2.3 km, and its width is 1.8 km. This lake is located in a very inaccessible mountainous area, at an altitude of 4,142 meters above sea level.

Both car and walking tours of the nature reserve are organized for travelers. By jeep you can get to a remote mountainous area in just a few hours, while walking usually takes at least two days. For nature lovers, the best way to explore the reserve is on foot; there are several specially designated areas on its territory where you can set up a tent camp.

The best time to visit the beautiful lake and walk around the reserve is considered to be from the beginning of June to the end of September, at which time the plateaus surrounding the lake are covered with carpets of bright colors. One of the main inhabitants of these picturesque places are butterflies; there are several dozen species of them. Already in November, the beautiful valley and lake are hidden under thick snow; it completely disappears only by May. During the cold season, excursions around the reserve are not conducted.

Peyto Lake, Canada

In Canada, you should look for one of the cleanest lakes in Banff National Park, where the world-famous Peyto Lake is located. This lake is located in an incredibly beautiful foothill area, its area is about 5.3 square meters. km. The length of the lake stretches for 2.8 km, and its average width is only 800 meters. The first to discover this amazing lake was traveler Bill Peyto, and the lake got its name in honor of its discoverer.

One of the main features of the lake is its unusual shape; if you look at it from a bird's eye view, it resembles a huge wolf's head. The water in the lake has a rich turquoise hue, which also attracts attention. Every year the lake is replenished with water from nearby glaciers. Mountain streams bring with them tiny particles of minerals into the lake, which make the color of the water so unusual. Nowadays, several comfortable recreation centers are equipped for tourists on the shore of the lake. Here you can have a wonderful rest for a few days and enjoy the natural splendor.

These places are especially attractive to fishing enthusiasts; the lake is home to rainbow trout, salmon, pike and other species of noble fish. Those who want to fish in this wonderful place should take care of purchasing a license in advance. Guests of the reserve can diversify their holiday with exciting walks; there are extensive forests along the shores of the lake. Here you can see many rare animals and birds, and in the summer, rare species of flowers bloom in the reserve.

Lake Baikal, Russia


In the south of Eastern Siberia there is a world famous landmark - Lake Baikal. It is the world's largest reservoir of fresh water and the most deep lake on the planet, its maximum depth is 1,642 meters. The area of ​​the lake is 31.7 square meters. km. The lake is interesting not only in itself, it is surrounded by unique natural landscapes. Many unique endemic animals live here, and you can also see a lot of rare plants.

Lake Baikal is of tectonic origin, its water is considered one of the cleanest in the world and is home to valuable species of fish. One of the main features of water is its high oxygen content, while the amount of minerals is very small. Lake Baikal is also one of the coldest in the world; the water temperature in it, even in the summer months, does not rise above +8 degrees Celsius.

One of the main unresolved issues related to the lake remains the theory of its origin. According to scientists, its formation was provoked by tectonic activity; the age of the lake is at least 25 million years. The inhabitants of the lake are of great interest to researchers; there are more than 2,600 species of them. More than half of the aquatic inhabitants are endemic and cannot be found in any other body of water in the world. One of the most important environmental problems of Lake Baikal is wastewater. Many rivers flow into the lake, the water in some of them is polluted by industrial waste.

Moraine Lake, Canada


In Canada there is the famous glacial lake Moraine, it is located in Banff National Park. This lake is very small, its area is only 500 square meters. meters, and the maximum depth reaches 14 meters. At the same time, it is difficult to find equals in the beauty of this lake. The discoverer of this unique natural attraction was explorer Walter Wilcox. When he discovered this lake, he could not stop admiring it for half an hour. Later, in his manuscripts, the scientist noted that these were the happiest half an hour in his life.

This lake is located in a very inaccessible mountainous area, so for a long time no one knew about its existence. The water in the lake, which fills it year after year during the melting of glaciers, has a rich sapphire hue. Against the backdrop of the surrounding mountains, the lake looks fantastic. The best time to visit the lake is considered to be June; at this time the peak of glacier melting occurs and the lake reaches its maximum size.

Travelers can visit Moraine Lake only from May to September; the rest of the year the mountain road is closed for safety reasons. You can easily get to the lake by car; the nearest large populated area is the city of Calgary. In recent years, organized excursions have been conducted to the lake, tourist route the bus runs. Half an hour’s drive from the lake there is a small mountain village, which will also be very interesting to visit as part of the excursion.

Lake Jenny, USA


Jenny Lake is located in northwestern Wyoming and is today part of Grand Triton National Park. This lake is also of glacial origin and is located at an altitude of more than 2,000 meters above sea level. According to researchers, the lake was formed about 12,000 years ago, its maximum depth reaches 129 meters, and its area is about 482 square meters. km. Despite the fact that this lake is one of the cleanest in the world, motor boats are allowed on it, which is actively used not only by researchers, but also by tourists.

The main route, formed along the shores of the lake, is called the Jenny Lake Trail; excursions here are conducted not only during the day, but also at night. Nearby is the beautiful Cascade Canyon, which is also an important attraction of these places. The name of the lake has a very interesting history. In 1872, one of the first large expedition groups, led by the Englishman Richard Lee, worked on the lake. This beautiful lake was later named after his wife Jenny.

Another attractive feature of the reservoir is the variety of fish species; fishing was allowed here several years ago. The most cherished catch of fishermen is trout; to go fishing here, you need to obtain a special license. Tourists are allowed to travel to these places only when accompanied by guides; among the inhabitants of the nearby forests there are many predatory animals, and bears are also found here. Just like many years ago, today the national park attracts hunters, and climbers also like to relax here.

Lake Pukaki, New Zealand


New Zealand also has many wonderful lakes worthy of tourists' attention. One of them is worth looking for on Yuzhny Island, where the beautiful Lake Pukaki is located. This lake of glacial origin has become famous throughout the world thanks to the rich blue color of the water, which, among other things, is also incredibly clean. The area of ​​the lake is 178.7 square meters. km, it is located at an altitude of more than 500 meters above sea level. This fabulously beautiful reservoir stretches for 15 km in length and its width is about 8 km.

Several years ago, Lake Pukaki became part of a large hydropower system; experts made sure that such use of the reservoir would in no way affect its environmental performance. For local residents, the appearance of the hydraulic unit was a real breakthrough; it was thanks to the lake that they finally received stable electricity.

Not everyone knows that initially the glacial lake was very small, its maximum depth was no more than 25 meters. When the construction of a hydraulic station began in the 40s of the last century, the volume of the lake was significantly increased. Initially, in the center of the lake there was a small island, which, as a result of the expansion of the reservoir, was flooded. The water in the glacial lake is always very cold, so not everyone dares to swim in its crystal clear azure water. Even at the height of summer, its temperature is no more than + 7 degrees Celsius. Local residents have many beautiful legends associated with the lake; it got its name in honor of one of the mythical warriors.

Lake Tahoe, USA


There's something amazing in California freshwater lake Tahoe, it is located in the picturesque foothills of the Sierra Nevada. This lake is well known to tourists; several popular ski resorts are located in its immediate vicinity. Lake Tahoe is the second deepest lake in the United States, with an average depth of 305 meters and an area of ​​about 495 square meters. km. Among the most beautiful lakes in the world, Tahoe is considered one of the most easily accessible; large roads run along the entire perimeter of the reservoir.

The lake was formed at the site of a geological fault in the earth's crust about 3 million years ago. Today, not only the lake itself with water of a fantastic heavenly color is of great interest, but also the coniferous forests surrounding it. Here you can see many rare species of pine and fir, as well as rare species of shrubs and grasses. The lake was discovered relatively recently, in 1844, its discoverer was Lieutenant John Fremont.

He explored these mountainous areas in search of a river, and discovered an incredibly beautiful lake, which a few years later was explored by scientists from all over the world. Most tourists began to visit these places after 1960, when the Winter Olympic Games were held at one of the local resorts. Since those times, an excellent tourist infrastructure has remained here; today there are comfortable hotels near the lake, and there are also many ski slopes of varying difficulty levels. Lovers of hiking will also find it interesting to relax here; exciting excursions are held near the lake at any time of the year.

Blue Lake, New Zealand


One of the cleanest and most unusual lakes on the planet with the complex name Rotomairewhenua is located in New Zealand; translated from the Maori language its name means “Blue Lake”. This miniature freshwater lake is located within the Nelson National Forest and is part of a complex system of lakes. Ecologists began to study the reservoir in detail only in 2011; they accidentally discovered that the water in the lake is extremely clean.

Visibility there can reach 80 meters. From year to year, the lake is fed by water from nearby glaciers. Flowing down from the mountain peaks, it passes through many natural rocks, which act as a natural filter. Largely due to its purity, the water in the lake has an amazing hue, which during the day varies from deep blue to light purple.

One of the first specialists to show interest in the lake was hydrologist Rob Mirriles. After admiring the crystal clear water, travelers should definitely take a walk through the forests and mountain ranges surrounding the reservoir. There are no tourist centers near the lake; it is extremely rare to meet travelers here. The main visitors to these picturesque places are researchers and ecologists; not so long ago, as a result of a major study, they equated the water in Blue Lake in properties and quality to distilled water.

Petermann River, Greenland


Some rivers are also striking in their amazing purity of water. An excellent example is the Petermann River, located in Greenland; it is known to a wide range of travelers under the unofficial name of the Blue River. The location of the river is the glacier of the same name, which melts in the summer and forms many small streams. They all converge into a single river, the water of which has a rich blue tint.

The incredibly beautiful and clean river poses a huge threat to the world ecology. In recent years, the Petermann Glacier has begun to melt four times faster, which is contributing to a significant increase in the water level of the world's oceans. According to researchers, the glacier will melt even more rapidly in the coming years, which could lead to serious environmental disasters. In the meantime, the crystal clear river is of great interest to scientists. They can estimate the composition of glacial waters that have been frozen for millions of years.

It is very difficult for ordinary travelers to reach this remote corner of the world with an incredibly harsh climate; this can only be done together with organized expedition groups. Now environmentalists are trying to take all possible measures to minimize the influx of glacier meltwater into the world ocean. In the coming years it may lose up to 100 sq. kilometers of ice, this amount of melt water would be enough to supply a large metropolis for 10 years.

Weddell Sea, Antarctica


Off the coast of West Antarctica lies the beautiful Lake Weddell, which is also one of the cleanest bodies of water on the planet. It bears its name in honor of the discoverer J. Weddell, who made an expedition to these places in 1832. The sea area is 2,900,000 square meters. km, and its maximum depth reaches 6,800 meters. In addition to the incredibly beautiful water of a heavenly hue, the sea is distinguished by a huge number of ice floes that float in it all year round.

This beautiful, clear sea is home to thousands of aquatic inhabitants, huge populations of whales, seals and fish live here, and penguins are also typical inhabitants of these places. Today the Weddell Sea is considered the cleanest in the world. The last major study of its water took place in 1986, the average visibility was estimated at 79 meters, which corresponds to distilled water.

Not all research groups, not to mention ordinary tourists, decide to sail on this sea; drifting ice poses a huge threat to ships. Many natural and physical phenomena are associated with the North Sea. The water in it never freezes, despite the fact that its temperature can reach -25 degrees Celsius. The Weddell Sea is the coldest and cleanest sea on the planet. To see it with your own eyes, travelers need to be part of one of the research expeditions, but they go to this harsh sea extremely rarely

On our planet there is great amount lakes They can differ strikingly from each other both in size, origin, and other indicators. Then how are they similar, and what is a lake in general?

It is not so easy to give a precise definition of this concept. For example, if we say that this is a body of water surrounded on all sides by land, then this will not be entirely correct. Since those into which rivers flow (or flow out of them) have a broken coastline.

If we claim that this is a fresh body of water, then what to do with Dead Sea and others in which the water is salty? We can say that they have no connection with the oceans. But known to everyone, located in South America, connects to the Caribbean Sea.

So what is a lake? It would be more correct to say that this is a body of natural origin on land. First of all, the lakes differ from each other in size. Sometimes in the mountains you can find small ones, only a few tens of meters long, while the largest lake on Earth - the Caspian Sea - has a length of more than 1000 kilometers.

Rainwater flows into lakes, rivers and streams flow into them, so they must be located at low points in the area. But this is not always observed. South American Lake Titicaca is located at an altitude of 3812 meters above sea level.

How are they formed?

To understand what a lake is, you need to find out how they arise. There are glacial reservoirs located in depressions of the earth's surface, formed under the enormous weight of an ancient glacier. These depressions gradually filled with melted glacial waters. Most often they are placed in large groups and have small sizes and depths. There are many of them in Finland, Canada, Siberia.

Located in high mountain basins. Sometimes it happens that such a lake appears right before our eyes - during mountain falls, the river bed is blocked and water accumulates near the dam that has arisen. Usually they are short-lived, and water quickly erodes the barrier, but there are exceptions. An example is the Pamirs.

The lakes formed in are elongated, narrow and very deep. There are many of them in Africa: Tanganyika, Nyasa and others. This is also the deepest lake in the world, Lake Baikal.

Reservoirs of tectonic origin can also have a shallow depth, for example, the Khmelevsky lakes, which are located in the eastern part. Four closed reservoirs are filled; not a single stream flows into them and does not flow out either.

Alpine lakes filled with glacial water are only fresh. But the Dead Sea, located in a basin, is so salty that there is no life in it.

In some lakes, the water, due to the presence of a large number of impurities in its composition, is not only salty, but also cloudy, which gives it a different color. But most bodies of water, especially small ones, have fresh and clean water. For example, in Leningrad region Lake Bezymyannye is located, which is considered one of the cleanest in Russia. The reason for this is the presence of a large number of springs and springs, constantly renewing and refreshing the water.

Some of the lakes regularly change their size, and their coastline is indicated conventionally on maps. Most often this depends on seasonal precipitation. Thus, Lake Chad on the African continent can change several times throughout the year.

Historical reference

The phrase “Red Sea” is a direct translation of the Greek “Erythra thalassa” (ancient Greek. Ἐρυθρὰ Θάλασσα ), Latin "Mare Rubrum", Arabic "El-Bahr El-Ahmar" (Arabic: البحر الأحمر‎), Somali " Badda Cas" and Tigrinya " Kay-Bahri"(ቀይሕባሕሪ). In modern Hebrew the sea is also called the Red Sea - “ ha-yam ha-adom”(‏הַיָּם הָאָדוֹם‏‎), but is traditionally identified with what is called in the Bible “Reed” (‏יַם סוּף‏‎).

There are several versions of the origin of the name of the Red Sea.

The first version explains the origin of the name of this sea from an incorrect reading of a Semitic word consisting of three letters: “x”, “m” and “r”. From these letters in ancient inscriptions the name of the Semitic people - the Himyarites - was made up, who lived in Southern Arabia before its conquest by the Arabs. In ancient South Arabian writing, short vowel sounds were not represented graphically in writing. Therefore, there was an assumption that when the Arabs deciphered the South Arabian inscriptions, the combination of “x”, “m” and “r” was read as the Arabic “ahmar” (red).

Another version makes the name of the sea dependent on one or another part of the world. In the mythical tales of many peoples of the world, the cardinal directions are associated with certain color shades. For example, red color symbolizes the south, white - the east, black (among a number of Asian peoples) - the north. Hence the name “Black Sea” does not mean “sea with dark, black water”, but “sea located in the north”. After all, the Turks called this sea Kara-Deniz, the ancient tribes who spoke Iranian languages ​​called it Akhshaena (dark), and the Scythians called it Tama, which is also associated with the meaning “dark”. As for the Red Sea, the word “red” seems to indicate its southern location, and not at all the color of the sea water.

According to another version, the sea was named so because of the seasonal bloom of microscopic algae Trichodesmium erythraeum near the surface of the water. An excess of the red pigment phycoerythrin in the alga causes a “blooming” of water in the Red Sea, and the latter becomes reddish-brown instead of blue-green.

One of the first descriptions of the Red Sea was made in the 2nd century BC. e. Greek historian and geographer Agatharchides of Knidos in his work “On the Red Sea (Erythraean).” In the 16th century the name was allowed "Suez" .

Physiographical sketch

General information

The Red Sea washes the shores of Asia and Africa: Egypt, Djibouti, Eritrea, Saudi Arabia, Israel and Jordan.

The area of ​​the Red Sea is 450,000 km², almost 2/3 of the sea lies in the tropical zone.

Volume - 251,000 km³.

According to various estimates, the length (in the north-south direction) ranges from 1932 to 2350 km, width - from 305 to 360 km. The shores are slightly indented, their outlines are mainly predetermined by fault tectonics, and almost along their entire length the eastern and western shores are parallel to each other.

The bottom topography includes: coastal shallows (up to a depth of 200 m), the widest in the southern part of the sea, with numerous coral and indigenous islands; so-called main trog- a narrow depression that occupies most of the seabed, on average to a depth of 1000 m; the axial trough is a narrow and deep trough, as if cut into the main trough, with a maximum depth, according to various sources, from 2604 to 3040 meters. The average sea depth is 437 m.

There are few islands in the northern part of the sea (for example: Tiran Island) and only south of 17° N. w. Several groups with numerous islands were formed: the Dahlak archipelago in the southwestern part of the sea is the largest, and the Farasan, Suakin, Hanish archipelagos are smaller. There are also separate islands - for example, Kamaran.

In the north of the sea there are two gulfs: Suez and Aqaba, which is connected to the Red Sea through the Strait of Tiran. A fault runs through the Gulf of Aqaba, so the depth of this gulf reaches great values ​​(up to 1800 meters).

The peculiarity of the Red Sea is that not a single river flows into it, and rivers usually carry silt and sand with them, significantly reducing the transparency of sea water. Therefore, the water in the Red Sea is crystal clear.

The Red Sea is the saltiest sea in the World Ocean. 1 liter of water here contains 41 g of salts (in the open ocean - 34 g, in the Black Sea - 18, in the Baltic - only 5 grams of salts per liter of water). During the year, no more than 100 mm of atmospheric precipitation falls over the sea (and not everywhere and only in the winter months), while 20 times more evaporates in the same time - 2000 mm (this means that every day more than half a centimeter evaporates from the surface of the sea water). In the complete absence of water supply from land, this water deficit in the sea is compensated only by the supply of water from the Gulf of Aden. In the Bab el-Mandeb Strait, there are simultaneously currents entering and exiting the Red Sea. Over the course of a year, almost 1,000 km³ more water is brought into the sea than is taken out of it. It takes only 15 years for the Red Sea to completely exchange water.

In 1886, during an expedition on the Russian corvette “Vityaz” in the Red Sea, waters with an abnormally high temperature were discovered at a depth of 600 meters:21. The Swedish ship Albatross also discovered similar waters in 1948, moreover, with abnormally high salinity. The presence of hot metal-bearing brines at great depths in the Red Sea was finally established in 1964 by an expedition on the American ship Discovery, when the water temperature from a depth of 2.2 km was 44 °C and its salinity was 261 grams per liter. By 1980, 15 places on the bottom of the Red Sea were discovered with similar waters, which, together with the adjacent bottom sediments, are highly enriched in metals: 33.

Geological structure and bottom topography

The Red Sea is very young. Its formation began about 25 million years ago, when a crack appeared in the earth's crust and the East African Rift Valley was formed. Under the influence of centrifugal force due to the rotation of the Earth, the African plate separated from the Arabian, and their reversal formed a “spiral” twisting to the northeast, and between them a gap formed in the earth’s crust, which gradually, over thousands of years, was filled sea ​​water. The plates are constantly moving - the relatively flat shores of the Red Sea are moving apart at a rate of 1 cm per year, or 1 m per century (Kendall F. Haven says that at this rate of expansion in the next 200 million years, the Red Sea will be as wide as the Atlantic Ocean) - but also at different speeds relative to each other: the movement of the African plate was very slow, while the Arabian plate moved much faster and, as a result, the Somali plate began to shift to the east. The spiral movement of the Arabian Plate led to the locking of part of the huge Tethys Ocean, which washed Africa, and subsequently the formation of the Mediterranean Sea. This is confirmed by the fact that rocks and minerals characteristic of Mediterranean Sea, were also found in Krasnoye. And further rotation of the Arabian and Somali plates opened a strait in the south, into which the waters of the Indian Ocean poured, ultimately leading to the formation of the Gulf of Aden. The movement of continental plates continued to influence the terrain. In the south, a large segment that broke off from the Arabian plate eventually closed the passage that formed between the African and Somali plates. The sea dried up here, and a valley was formed, known as the Afar Triangle. This geologically unique region has given scientists a lot of information about the history of the planet and the evolution of mankind. The lowest segment of the Afar Triangle is currently slowly sinking under water and will eventually fall back below sea level.

The changes, of course, affected not only this local area of ​​the earth's surface. The shift of the Syrian-African fault to the north led to the formation of the Bay of Suez. The Arabian and African plates continued to move at different speeds (this difference in speed was determined by the different distances of the plates from the axis of rotation). The inevitable friction between the plates formed another valley, very similar to the bed of the Red Sea. This fault starts from the Strait of Tiran and goes further north to the Gulf of Aqaba, as well as the valleys in which the Dead Sea and Arava lie. The end point of these valleys is Syria. Continuous tectonic activity shifted the Bay of Suez to the north - towards the Mediterranean Sea. Human intervention completed this process in 1869 with the opening of the Suez Canal. The waters of the Mediterranean Sea flowed into the Red Sea, and the migration of underwater flora and fauna began in both directions.

Hydrological regime

The Red Sea is the only body of water on Earth into which no river flows.

Strong evaporation of warm water turned the Red Sea into one of the saltiest on the globe: 38-42 grams of salts per liter.

There is intense water exchange between the Red Sea and the Indian Ocean. In winter, the South-West Monsoon Current is established in the Indian Ocean, starting in the Bay of Bengal, turning into the Western Current, which branches, and one branch goes north to the Red Sea. In summer, the monsoon current, which begins off the coast of Africa, is joined in the Gulf of Aden area by a current from the Red Sea. In addition, the Indian Ocean contains deep water masses formed by dense waters flowing from the Red Sea and the Gulf of Oman. Below 3.5-4 thousand meters, bottom water masses are common, forming from the Antarctic supercooled and dense salty waters of the Red Sea and the Persian Gulf. .

Climate

The climate on the coast of almost the entire Red Sea is tropical desert, and only the far north has a Mediterranean climate. The air temperature in the coldest period (December-January) during the day is +20-25 °C, and in the hottest month - August, it exceeds +35-40 °C and even sometimes reaches +50 °C. Thanks to the hot climate off the coast of Egypt, the water temperature does not drop below +20 °C even in winter, and reaches +27 °C in summer.

Bioresources

In terms of quality and variety of corals, marine flora and fauna of the Red Sea has no equal in the Northern Hemisphere. The tourism boom that has taken place in recent years [ When?] the Egyptian coast of the Red Sea, is largely associated with the unique and incredibly rich underwater world of this tropical sea, the popularization of scuba diving.

The coral reefs stretching along the entire Egyptian coast are a kind of life center that attracts many fish. The variety of coral shapes is amazing, which can be round, flat, branched, and also have other fantastic shapes and colors - from soft yellow and pink to brown and blue. But only living corals retain color; after death, they lose their soft covering tissue and only a white calcium skeleton remains.

Bottlenose dolphins, various species of striped dolphins, and killer whales are common in the Red Sea. It is quite possible to meet underwater with a green turtle. Echinoderms live on the seabed - sea cucumbers. There are sharks; they have chosen the coast of Sudan. Moray eels, adapted to life on reefs, can reach 3 meters in length and have a rather terrifying appearance. Usually, if not teased, they are not dangerous to humans, but the bite of fish can be dangerous: cases of unprovoked attacks on scuba divers have been known.

Cities

Coastal cities:

• Aqaba (العقبة)
• Arkiko (ሕርጊጎ)
• Asseb (ዓሳብ)
• Dahab (دهب)
• Eilat (אילת)
• Halaib (حلايب)
• Hodeidah (الحديدة)
• Hurghada (الغردقة)
• Jeddah (جدة)
• Marsa al-Alam (مرسى علم)
• Massawa (ምጽዋ)
• Nuweiba (نويبع)
• Bur-Safaga (ميناء سفاجا)
• Port Sudan (بورت سودان)
• Sharm el-Sheikh (شرم الشيخ)
• Soma Bay (سوما باي)