Patterns of the location of the continents. The face of the earth: land and water surface of the earth
We remember
How is the planet Earth different from other planets in the solar system?
Thinking
Why it would be more logical to call our planet a planet
Ocean?
Much of the surface the globe covered with water. water area -World Ocean- occupies 71% of the Earth's surface. Above the water is land - continents and islands. Land accounts for only 29% of the Earth's surface.
Continents- These are huge areas of land, surrounded on all sides (or almost on all sides) by water. There are six continents on Earth: Eurasia, Africa, North America, South America, Antarctica, Australia (Figure 1). The largest of the continentsEurasia. It is connected by a small piece of land to the second largest mainland.Africa. Third and fourth in terms of area areNorth America
and South America,they are also interconnected by a narrow piece of land.Antarcticais the fifth largest continent. It is covered by a thick ice sheet. This is the only continent where people do not live permanently. The smallest continent is located in the southern hemisphereAustralia.
Picture 1- Continents and oceans
Since ancient times, land has been divided not only into continents, but also intoparts of the worldhistorical regions. There are also six parts of the world:Europe, Asia, Africa, America, Antarctica, Australia and Oceania (Figure 2). Parts of the world Europe and Asia are on the same continent Eurasia, and the continents North America and South America form one part of the world - America.
Figure 2- Parts of the world
The land of our planet, along with the continents, is also made up of islands.Islands- These are small areas of land compared to the continents, surrounded on all sides by water. There are a lot of them on Earth. There are single islands and groups of islands lying at a short distance from each other - they are called archipelagos. The largest island on earthGreenland. The largest islands also include New Guinea, Kalimantan and Madagascar.
Huge depressions on the surface of the planet are occupied by the waters of the oceans. Continents and islands divide it into separate oceans:Pacific, Atlantic, Indian, Arctic . The Pacific Ocean is the largest, occupying almost half the area of the World Ocean. The Atlantic Ocean is half the size of the Pacific. From north to south, it has the same length as the Pacific, and from west to east it is much narrower. Indian Ocean the third largest, but three continents can fit in its area. The Arctic Ocean is the smallest ocean in terms of area, located in the north of the planet.
Let's generalize!
The surface of our planet is made up of land and water - the oceans.
Land consists of continents and numerous islands. There are six continents: Eurasia, Africa, North America, South America, Antarctica, Australia. Continents and islands divide the World Ocean into four oceans: Pacific, Atlantic, Indian and Arctic.
Answer questions, complete assignments
1. What is a mainland?
2. How many continents are on Earth? List them in order of decreasing area.
3. What do we call the oceans?
4. How many oceans are on Earth? List them in order of decreasing area.
5. On what continent and in what part of the world is the Republic of Belarus located?
6. What is called an island?
7. What is the name of the largest island in the world?
Do practical work
"Application to contour map geographical objects"
1. Using the physical map of the hemispheres, label on the contour map:
a) the continents
b) oceans;
c) the largest islands and groups of islands that you have found on physical map hemispheres.
The land of the globe is fragmented into a number of huge massifs and smaller areas.
Large blocks are called continents, or continents, small islands. The smallest of the continents (Australia, 7.6 million sq. km) is four times larger in area than the largest of the islands (Greenland, 2.2 million sq. km).
There are seven continents. The boundaries between the continents are not always distinct. In this regard, only Australia and Antarctica are beyond doubt. The Suez and Panama Canals serve as conditional borders - the first between Africa and Asia, the second between North America and South America. But it is especially difficult to draw a line between Europe and Asia, which, in essence, constitute a single continent - Eurasia. Now the Caucasus and Transcaucasia are classified as Europe, and the eastern border of Europe is drawn along the Ural Mountains, Mugodzhary and the river. Embe.
Asia is not only the largest continent, but also the highest. It is followed in descending order by average height by: Africa, North America, South America, Europe and Australia. Antarctica stands apart. Its huge average height is explained by the presence of a powerful ice sheet on it, the thickness of which reaches 1600 m.
And in the outlines of the continents, and in their grouping, and in the structure of their surface, there are features that have long attracted attention.
All continents, with the exception of Antarctica, are grouped in pairs: North America with South, Europe with Africa, Asia with Australia. Each pair forms a continental ray, and all the rays converge towards the northern polar space, forming the so-called "continental star", which is especially clearly visible on maps built in stellar projection.
In each pair, the northern mainland is separated from the southern mainland by a fault area earth's crust, characterized by the presence of deep seas, an abundance of islands (fragments of this fragmented crust), frequent and strong earthquakes and intense volcanic activity.
The characteristic shape of the continents is also striking, resembling triangles, with their bases facing north. The northern parts of the continents are wide, and to the south the continents seem to wedge out. With regard to Europe and Asia, this is also true if we consider them as something united (Eurasia). The shape of Antarctica is pear-shaped, that is, also generally triangular; the narrow part is turned towards South America.
Other features are also noted, which, however, are not characteristic of all continents. So, each of the southern continents in the west has a concavity (South America has the Arik Gulf, Africa has the Gulf of Guinea, Australia and Tasmania have the Great Australian Gulf), and a convexity in the east. Some continents along their eastern outskirts are framed by garlands of islands, while there are no such garlands on the western side. At the same time, island garlands form arcs, sometimes strongly curved, but always bulging to the east: the Antilles arc, a garland of islands connecting South America with Antarctica (South Georgia, South Sandwich, South Orkney, South Shetland), a huge scalloped arc of the East Asian islands (Kuril , Japanese, Philippine), to which the Aleutian Islands can also be attributed, although they are attached to the American mainland.
The current level of our knowledge does not allow us to go further than a simple statement of the features outlined above. Attempts to explain all or some of them have been made repeatedly. But none of the proposed explanations is indisputable. Therefore, we limited ourselves to presenting the actual data. Even in this form, knowledge of them makes the idea of earth's surface more slender and organized.
If you find an error, please highlight a piece of text and click Ctrl+Enter.
Dimensions. In terms of size, among all the continents, they stand out: Eurasia is the largest in area (52.2 million km 2), which is 37% of the land surface; - the smallest (7.68 million km 2), it is sometimes called the mainland-island, it is only 3.4 times larger than the largest island of our planet Greenland (2.2 million km 2), its territory will fit twice within the borders of Russia (17.07 million km 2). The second largest continent of the planet is Africa (29.2 million km 2), it can accommodate three Europe (9.3 million km 2) or Russia together with Canada (9.97 million km 2) and Greenland. The third largest continent is North America (20.36 million km 2), which is 2.6 times less than the area of Eurasia. Next come South America (18.13 million km 2), which is slightly more area Russia, and Antarctica (12.4 million km 2).
In size, all the southern tropical continents (Africa, Australia, South America) are inferior to Eurasia. Even the largest of them - Africa is almost half the size of Eurasia in area.
In Eurasia, there are 2 parts of the world - Europe and Asia. This division has a traditional cultural and historical basis. The idea of Europe and Asia as different parts of the world developed in ancient times, much earlier than geographical ideas about the true size and contours of the entire continent as a whole were formed. Therefore, for a long time there was a concept of Europe and Asia not only as different parts of the world, but also as different continents. In physical and geographical terms, it is purely conditional, just as the border between Europe and Asia is conditional.
Configuration. S.V. Kalesnik, noting the main features of the earth's surface, points out the following points:
- All continents, except Antarctica, are grouped in pairs: North America with South, Europe with Africa, Asia with Australia. Each pair forms a "continental ray", and all the rays converge towards the northern polar space, forming together a "continental star". E. Reclus (1868) called this feature the law of three mutually parallel double continents.
- All continents are shaped like wedges or triangles, with their base facing north. The pear-shaped (triangular) shape is also characteristic of Antarctica.
- Each of the southern continents in the west has a concavity (Gulfs of Arik, Guinea, Great Australian), and in the east - a convexity.
- In every continental ray southern mainland shifted to the east relative to the north, and is not a direct meridional continuation of it.
When interpreting the features noted above, one proceeds from the nature of the ascending and descending movements in the lithosphere and the processes of compression of the Earth. So in the northern hemisphere, the continents wedge out to the south because secular zonal subsidence of the equatorial belt is superimposed on the meridional continental uplifts (due to the general secular decrease in the polar compression of the Earth). The wedging out of the continents in the southern hemisphere is caused by a higher rate of its volumetric compression compared to the northern hemisphere.
With the lowering of the masses of the lithosphere of the equatorial belt and, therefore, with their approach to earth's axis, as a result of which they acquire an additional rotation speed, the crescent shape of South America and Africa is associated (the presence of concavity in the west and convexity in the east in their outlines), as well as the rotation of Australia clockwise.
The predominance of uplifts of the lithosphere in the northern hemisphere and subsidence in the southern hemisphere also causes the displacement of the northern continents to the west, and the southern ones to the east. This is a consequence of the effect of torsion under the action of an additional tangential force that arises according to the law of conservation of angular momentum.
The general pattern, which is to some extent inherent in all the continents of the Earth: wide in the northern part, they narrow towards the south. Only for the configuration of Eurasia and Australia, this is less typical, in their form - they are isometric. Both of these continents are more elongated from west to east (Eurasia by 16 thousand km, and Australia by 4100 km) than from north to south (the largest length of Eurasia in this direction is 8 thousand km, and Australia is 3200 km).
Both American continents and Africa are elongated along the meridian: the length of Africa is 20 0 east. – about 68 0 North America at 100 0 W - about 52 0 , South America at 70 0 west longitude - about 66 0 . They differ in the expansion in the northern part and the narrowing of the mainland in the south: South America reaches its maximum width (5150 km) at 5-8 0 S.l. in the south, the width of the mainland does not exceed 400 km. Africa is characterized by an unequal area north and south of the equator. The northern half of the mainland is more than twice as wide as the southern one: from Cape Verde (Cape Almadi) in the west to Cape Ras Hafun in the east, the distance is 7500 km; the width of the southern half does not exceed 3100 km. North America reaches its largest size in temperate and polar latitudes, stretching from west to east at 112 0, which corresponds to seven time zones, or 4560 km, along the line of the northern tropic, within Mexico, the distance from Pacific Ocean to the Atlantic does not exceed 10 0 or 1000 km.
Coastline outline. The northern continents (Eurasia and) are distinguished by a significant indentation of the coastline. Peninsulas occupy about a quarter of the area of each of them.
The coasts of Eurasia are the most indented. Oceans and seas, penetrating deeply into the mainland, strongly dismember its outskirts. The most narrow and deeply dissected by the seas Western part Eurasia outside Russia, i.e. overseas Europe: 1/3 of its surface falls on islands and peninsulas and the greatest distance to the sea is only 600 km. Compared to Europe, Asia is very compact and solid. However, islands and peninsulas occupy 24% of its territory.
- The displacement is called the vector connecting the start and end points of the trajectory The vector connecting the beginning and end of the path is called
- Trajectory, path length, displacement vector Vector connecting the initial position
- Calculating the area of a polygon from the coordinates of its vertices The area of a triangle from the coordinates of the vertices formula
- Acceptable Value Range (ODZ), theory, examples, solutions