Awarded the status of the driest continent on Earth. The climate and topography of the continent are quite monotonous, which cannot be said about the animals and flora. The bulk of Australia receives a large number of atmospheric precipitation, and the main watershed is located east of the center of the continent. This explains strange shape drainage systems.
Climate of Australia
The main part of the continent is located on the Australian Plate. The relief was formed during the Archean folding. For this reason, there are almost no mountain ranges here. Climatic conditions resemble those African continent. While there is snow in Eurasia, Australia is in the grip of a hot summer. average temperature in the center of the continent - about 35 ºC. The winter period begins in June and lasts until September. The average air temperature is about 10 ºC. Frosts are possible at night. Most of the territory receives no more than 250 mm of precipitation throughout the year.
The Australian continent is located in three natural areas: tropical, subtropical and subequatorial. About 44% of the area is occupied by deserts, of which there are 8. South part continent is characterized by hot and dry in summer, and winter, on the contrary, is rainy. Northern Australia is influenced by the South Trade Wind Current. In summer there is heavy rain, and in winter it is clear and dry.
Tectonics
Most of the continent's mountain systems disappeared as a result of weathering processes over several billion years. highest peak Australia - Mount Kosciuszko. The main part of the hills has a height of less than 200 m. About 40 million years ago, the Great Dividing Range was formed. It is significantly deformed mountain system, and also the only one here.
The continent is located far from the contact points of tectonic plates. This circumstance explains the fact that there are no volcanoes in Australia. The junction is located in Oceania. There is high volcanic activity in this place.
Australia's inland waters: at a glance
On the continent small indicator Basic quantity water arteries dries out. The rivers, starting on the eastern slopes of the Dividing Range and located in Tasmania, are year-round. Australia's inland waters in the west dry up during the summer heat. Most of the territory has streams and rivers flowing inland. The boundaries of the basins collecting water are poorly defined.
Rivers
The inland waters of Australia, photos of which are in the article, are presented main river- Murray. It has three large tributaries that collect moisture from an area of over 1 thousand km 2. The sources of the main tributaries are located 200 km from the eastern coast of the continent. As the current flows, they unite into large watercourses flowing along winding channels towards the sea. The length of the Murray is 2575 km. The lower reaches are navigable for 970 km from the mouth.
Sandbanks are an obstacle for large water transport. Due to their location near the mouth, seagoing vessels cannot navigate the Murray. The Murrumbidgee is a tributary of the continent's largest river. Its length is about 1690 km, the river originates in the Kuma region. " Snowy mountains"- a hydroelectric power station that regulates the joint flow of these two rivers.
Darling is second major influx Murray, collecting water from the western slopes of the Dividing Range. The length of this river is 2740 km. In its bed and on some tributaries there are dams that regulate the flow all the time, except for severe droughts.
Water mode
The features of Australia's inland waters are not limited to this. The main part of the continent's territory has a separate drainage or belongs to internal basins. An example of such a zone is the Western Plateau. In numerous channels, water appears rarely and for a short period of time. The drains lead to dry lakes or wetlands.
A huge territory, the area of which is 1143.7 thousand km 2, belongs to the lake basin. Air, one of the ten largest on Earth. The basin includes the Cooper Creek, Diamantina and Georgina streams. Their angle of incidence is very small, the channels are winding and intersect in places.
Studying inland waters Australia 7th grade secondary school. From curriculum It is known that the river beds of the basin are almost always dry, and flows of water appear in them only after heavy rainfall. At this time the width water flows reaches several kilometers. However, they almost always disappear before reaching the lake basin. Water appeared in it for the first time only in 1950, during the entire period of observation by Europeans who arrived on the mainland.
Australia's climate and inland waters are interconnected. The consequence of low rainfall was the instability of most of the continent's rivers. For this reason, they cannot be used for human benefit. There are few areas suitable for the construction of dams, especially in the central part of the mainland, where the problem of water supply is very acute. To solve it, many full-flowing reservoirs are needed.
In the driest areas, large amounts of water simply evaporate. Only in Tasmania do Australia's inland waters have stable year-round flows.
Lakes
Australia's topography, climate and inland waters have caused a large number of dry lakes. The bottom of these basins is covered with clay rich in salts. IN in some cases There are lakes filled with water. However, they are saturated with salts and silt at shallow depths. Most of them are in the western part of the continent, and the largest are in the southern part (Eyre, Frome, Torrens, etc.).
In the southeast of the mainland there are many lagoons with salt-rich water, which are separated from the sea by sand barriers. Tasmania is a region where you can find the most big lakes continent with hydroelectric power stations built on some.
The groundwater
Australia's groundwater inland water is a vital resource. Most rural settlements supplied from this source. The areas occupied by underground pools are huge (over 3240 thousand km 2). Most of them contain dissolved solids that are unsuitable for irrigation. However, this water can be used for livestock farms.
Under the ground of the continent is the largest on the planet, the Great Artesian Basin. Its area is 1751.5 thousand km 2. The waters located underground contain large amounts of salts. However, without this source of moisture, the mainland would be at risk. There are smaller artesian basins in other areas of the continent.
Poor in surface water, which is due to the dominance of dry tropical climates on the mainland and the absence high mountains with snow and... there are few rivers and lakes, about 60% of the continent's territory does not flow into the ocean. No other continent has such a relatively large area.
The main part of the continent, especially its interior desert and regions, is characterized by temporary drains - cries. Water appears in them only after rare rains and on a short time. The remaining rivers of the mainland belong to the Indian and. The rivers of the basin are short, shallow, and often dry up during the dry season. To the pool Pacific Ocean include rivers flowing from the eastern slopes of the Great Dividing Range. These rivers are full of water throughout the year, as there is a lot of rainfall here; short and rapids. Most of the continent's rivers are fed primarily by rain, while others are mixed.
The most significant river system Australia - a river with a tributary of the Darling. The Murray (2570 km long) originates in the Australian Alps and is fed not only by rainwater, but also partly by snow water. In summer the river is full of water, during the rainy season it often overflows its banks, and in winter it becomes shallow. The main tributary of the Murray is the Darling, Australia's largest (2740 km). But this river is shallow. The water level varies greatly depending on the seasons (up to 8 m above low water). IN dry time The Darling does not always carry its waters to the Murray and breaks up into separate reservoirs.
There are about 800 lakes in Australia. Most of them are relict lakes, the basins of which were formed during wetter geological eras. Many of the modern lakes of Australia (Torrance, Frome, Amadies, etc.) are dry basins filled with loose clay-salt marsh silt, covered with a crust of salt or gypsum. They fill with water only after rare rainfalls, which occur once in Western Australia for several years.
The largest lake in Australia is an endorheic lake salt Lake Air. It lies in a depression 12 m below sea level. In the dry season, Lake Eyre splits into many separate lakes, and during the dry season torrential rains turns into a vast expanse of water with an area of about 15 thousand km2.
Against the backdrop of a sparse and almost complete absence of fresh lakes, the amazing wealth of Australia is striking. The area of all artesian basins occupies 1/3 of the continent's territory. More than 15 artesian basins are confined to basement syneclises
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Every schoolchild knows that the driest continent on Earth is Australia, and why it is called Green continent, only professional historians and geographers now know. The annual rainfall here is five times less than in Africa and eight times less than in South America- regions that cannot boast of a surplus water resources. For this reason, there are no large deep rivers in Australia, especially most observed here hot weather, and Australian waterways have no other source of water replenishment other than rain. Of course, on the Green Continent there are relatively big rivers, most of which are located in the southeast of the mainland. These include, originating in the Great Dividing Range, the Murray River, which never dries up. Moreover, the regular melting of snow in the upper reaches of the river allows it to remain navigable for most of the year, and this very rare for local natural waterways. Even its tributary, the Darling, located north of the main channel of the Murray, never completely dries up. And this despite the fact that it does not have such a “gift” as melt water from the Great Dividing Range. True, during the dry period the Darling becomes very shallow, but still remains a stable source fresh water in the region.
In other regions of Australia, whose rivers do not flow into the ocean, a typical picture is when a river that was deep just yesterday becomes so shallow in just a few days that even a cat can ford it. Or worse, it dries out completely, exposing its bed. These waterways are called "creeks" in the local dialect, and the most famous of them is Cooper Creek. In general, in Australia, the prefix “cry” to the name of a river is quite common, since most local waterways “live” only during the rainy season. Regarding Australian lakes, the situation is not much better. Most of them are so salty that the lake water is not only impossible to drink, but cannot even be used for domestic needs, including for watering fields. There are very few relatively large lakes on the mainland and most of them are located in the Central Lowlands - these are Lakes Torrens and Lake Eyre. For similar natural water bodies The mainland is characterized by the absence of clear boundaries, which can change several times a year. For example, Eyre, for most of the year, is a network of small reservoirs that turn into a full-fledged lake only with the arrival of seasonal rains in this region. Moreover, Air is filled with water with a long delay, since rainwater It penetrates into the interior of the continent very slowly: the rainy season in the northeastern part of the continent begins in January, and the lake is replenished with water only in May-June.
It is clear that with this state of affairs on the mainland, great importance for Australia have waters located in the bowels of the Earth. Unfortunately, they are located so deep below the surface that they sometimes have to be mined from almost a kilometer deep. However, there are also regions where groundwater comes very close to the surface and can be “reached” from a depth of up to 100 meters. True, there is one problem, expressed in increased content sulfur in groundwater, which cannot be used without preliminary purification. But sometimes it's the only way to ensure a normal water supply, which is used, albeit not for the needs of the population, then for irrigation of agricultural land. But not everything is as bad as it might seem at first glance. Deep in the bowels of the Australian soil there is the Great Artesian Basin, from which water is already extracted today for domestic and other needs. How much is in it clean water, scientists still cannot say for sure, but apparently, it will last until the middle of this century. And then Australia will face an insoluble problem - how to provide the continent with clean and potable water.
Australia is the driest continent on Earth. It receives 5 times less precipitation than and 8 times less than. This is why there are no large deep rivers in Australia. More than half of the continent does not drain into the ocean. However, this does not mean that rivers are completely absent in Australia. Since the climate of the continent remains hot throughout the year, the predominant type of nutrition for its rivers remains rainwater. As you remember from the climate topic, greatest number precipitation falls in the southeastern part of the continent. That is why the largest are concentrated here: first of all, it is largest river mainland Murray with the Darling tributary. Originating on the peaks of the Great Dividing Range, these rivers do not dry out completely; moreover, the Murray remains deep and suitable for navigation throughout the year, as it is also fed by the melting snows of the Great Dividing Range. At the same time, the Darling, whose source is located much further north, in the lower mountains, where there is no snow, is largely dependent on the rainy season and becomes very shallow during the dry period.
The interior of desert areas that do not have drainage into the ocean are characterized by special temporary periods that completely dry out in hot season year watercourses called creeks, the most famous of which is Cooper Creek.
The lakes of Australia are characterized by significant salinity. There are very few large lakes on the mainland; these include only reservoirs located in the Central Lowlands: Lakes Eyre and Torrens. The lakes of Australia do not have clear permanent shores, as they dry out greatly during drought. Thus, Lake Eyre (pictured) turns into a network of small lakes, but fills up again with the arrival of the rainy season in northeastern Australia - from the overflow of the rivers that feed Lake Eyre. It is worth noting that water penetrates into the interior of the continent with a long delay. So the rainy season begins in Australia in the middle of summer, that is, in January, and the lake overflows already at the end of autumn - the beginning of winter: April, May, June.
Groundwater is of great importance to Australia. In some places it comes very close to the surface, sometimes it has to be mined from a depth of more than a kilometer. Use of Australia's groundwater for economic use difficult because they contain large amounts of sulfur, however, this is often the only way to get water. Fortunately, Australia’s groundwater reserves are huge; deep under its surface, the Great Artesian Basin stretches from north to south of the continent. But even these reserves are gradually drying up, and today Australia faces a huge ecological problem conservation and conservation of underground artesian waters continent.
Australia is a continent discovered by the Danes in the 17th century. Much time has passed since then, and millions of people have settled on the mainland. Despite most beautiful world– rich flora and fauna, rare species plants, animals, most of the continent remains uninhabited. What is the reason? The fact is that Australia is extremely poor in surface water and most of it is in deserted deserts.
Australia's problems
Australia is very poor in surface water. In addition, they are not only small, but also unevenly distributed, scattered throughout the continent. The shortage of water is due to the fact that the mainland is dominated by dry tropical and subtropical climate, there are no mountains with glaciers and snow-capped tops. There are very few rivers and lakes here; more than 60 percent of the territory does not flow into the ocean. This fact significantly distinguishes Australia from other continents. The main territory falling on desert and semi-desert areas exists thanks to temporary drains - creeks. The water in the springs is collected after heavy rains and showers. The remaining rivers belong to the Pacific and Indian Ocean basins. Rivers related to Indian Ocean, shallow and short. During hot periods they dry out, thereby leaving nearby areas without a source of water. The rivers of the Pacific basin are full of water throughout the year. They flow down from the Great Dividing Range. This area accounts for most of the precipitation. Unlike Crimea, Miskhor housing.
Water resources
Today there are more than 800 rivers in Australia, but not every body of water is filled with water all year round. During dry periods, they are covered not with water, but with a thick layer of salt and gypsum and are filled with water only after rare showers. The largest lake Australia is Lake Eyre. It extends over 15 thousand square kilometers. Locals They call it the “dead heart” of the mainland. Water from many creeks accumulates here, but deserts absorb most of the water. It is rare that Eyre can show all its water beauty in 15 thousand km2. Despite the disadvantage surface waters in Australia, this continent is the most beautiful place on the planet where they live rarest representatives flora and fauna.
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