Subdivisions of topical geography
Приложение
Примерный список текстов по дисциплине
Ocean Tides
If you are a sailor or a fan of high-seas adventure films, you have probably heard someone say, “We sail with the tide.” As the earth turns on its axis, the gravity of the moon pulls up a crest of ocean water, forming tides. Tides occur because the gravitational pull of the moon is strong on the side of the earth facing the moon, and weaker elsewhere on the earth. The height of the tide varies with the position of the moon. Tides are very long period waves, usually 24 hours long.
As the earth-moon system rotates about its center of mass, the force of this moving system produces two tidal crests, one on the side of the earth facing the moon and one on the opposite side. These tidal crests circle the earth in 24 hours and 50 minutes. Why does it take the tide more than a day to circle the earth? The extra 50 minutes are needed because the moon is traveling around the earth in the same direction in which the earth rotates. This means that the earth has to turn for 24 hours and 50 minutes in order for the same place to be directly under the moon. We speak about an ideal case – the earth would have two tides every 24 hours and 50 minutes if there were no continents. The continents, however, slow down the progress of the tides. Special charts show the times of the day when high tides or low tides occur at different locations on Earth.
The average tide is 0.55 m high in the open ocean. However, the height may reach 2 m to 3 m as the tide runs into a coast. The world-record tide occurs at the head of the Bay of Fundy, in Nova Scotia, Canada. There the tide may reach a height of 14 m.
The sun also produces tides. The sun, of course, is much larger than the moon, but it is also much farther away. The gravitational attraction of the sun is much stronger than the moon’s, but it does not change much from place to place. As a result, solar tides are only about half as high as lunar tides.
When the moon and sun are in a straight line with the earth, the height of the lunar and solar tides add up. The tides that result from this alignment are called spring tides. The name “spring tide” does not refer to the spring season, but to the “springing up” of the water. Spring tides occur twice during a lunar month: at full moon and at new moon. When the moon and sun are at right angles to each other, as seen from the earth, very low tides, called neap tides, occur. Neap tides also occur twice a month – midway between the spring tides.
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Under special circumstances, strong, dangers tidal currents can develop. These strong currents develop most often in narrow passages connecting bodies of water that have tides at different times of the day. The most famous of these is Charybdis, a tidal vortex that develops in the Strait of Messina, between Sicily and mainland Italy.
I. Look at the text and find a word which means the same as:
a. An imaginary line around which the Earth moves
b. To turn round a fixed point or axis
c. A map or a diagram, especially of a sea area
II. Multiple choice. Choose the best answer
1. The sides of the earth away from the moon will be in:
a. Low tide b. High tide c. Spring tide d. Neap tide
2. How long does it take for tidal crests to circle the earth?
a. 24 hours b. 50 minutes c. 24 hours and 50 minutes
3. In what way do the continents influence the progress of tides?
a. Don’t influence at all b. Slow down c. Speed up
4. Solar tides are:
a. Much higher than lunar tides b. Not so high as lunar tides
b. c. As high as lunar tides
5. High tides that occur monthly are called:
a. Spring tides b. Seasonal tides c. Tidal crests d. Neap tides
Geography - A Study of the Earth and What It Holds
1. Read and translate the text
The distribution of things on the face of the earth can be investigated and analysed in either of two ways. One approach is called topical geography, or sometimes systematic geography. This approach involves the investigation and analysis of such phenomenon as the earth's land forms, its climate, its political divisions, or its agricultural characteristics.
The other approach is called regional geography. It focuses attention upon a particular area or region. Within the region it investigates the distribution and association of elements which give the region its distinctive character.
Subdivisions of topical geography
Topical geography may by focused on physical or human phenomena. Analysis of the distribution of landforms, climates, water, soils, minerals, and similar factors is called physical geography. The principal branches of physical geography are geomorphology, climatology, biogeography, oceanology and soil geography. Certain aspects of physical geography, in turn, are sometimes studied separately. These include the plant geography, animal geography, geography of minerals and other aspects. The speciality which treat the form, size, and movements of the earth is called mathematical geography. Human geography analyses the distribution of human phenomenon. Economic geography includes such specialities as the geography of manufacturing, transportation geography, commercial geography. Political geography emphasizes the pattern of the earth's political sovereignties. A specialized field of topical geography known as urban geography, is devoted to analysing of the distribution of cities and things within them. Cartography takes a special place among geographic studies.
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