Ebb and flow on Earth.

The Moon, being the closest to the Earth and the largest in mass space body, has the greatest gravitational effect on it, causing tides and low tide in all shells of the Earth: lithosphere, atmosphere, hydrosphere and biosphere.

On Earth, there are simultaneously two tides at the nearest point to the Moon and the most distant one, and two low tides at points located at an angular distance of 90 ° from the Moon-Earth line. During lunar day Earth has two high tides and two low tides. A complete tidal cycle between successive high tides (or low tides) is completed in 12 hours 25 minutes, and between high and low tides 6 hours 12 minutes 30 seconds pass.

Simultaneously with the lunar tides, there are also solar tides with a total period of 24 hours, but they are 2.2 times weaker than the lunar ones due to the great distance of the Sun from the Earth. Lunar and solar tides add up to new moon and full moon (syzygy flushes) and subtracted in the first and last quarter (square tides). The former are about 40% higher than the latter.

The planetary significance of tidal waves lies in the fact that tidal friction arising from the movement of liquid and (to a lesser extent) solid waves leads to deceleration axial rotation Earth and its satellite. For this reason, the Moon has long ceased its rotation around its axis and is constantly facing the planet on one side. They cause daily vertical displacements of the earth's surface up to 50 cm. Since the mass of the Earth is 81 times the mass of the Moon, the magnitude of tidal acceleration on the surface of the satellite will be about 20 times greater than on Earth, and the theoretical height of a solid tide can reach several meters.

The diameter of the Earth is about 12,750 km. The earth has a shape ellipsoid, slightly flattened along the axis of rotation. At the Earth, the polar radius (6357 km) is shorter than the equatorial one (6378 km) by 21.4 km. Later it turned out that the flattening of North Pole 30 m less than that of the South. Weight as a whole decreases from the poles to the equator by 6 g per 1 kg (on spring scales).

spherical shape Earth causes a decrease in the angle of incidence sun rays on the earth's surface from the equator to the poles and, as a result, the formation of several thermal zones. Thermal belts, in turn, along with the size and mass of the Earth, a certain distance from the Sun cause a regular change in many natural processes and the component in the geographical envelope in the direction from the equator to the poles, i.e. latitudinal zonation.

At the same time, one feature is noted: in equatorial and tropical latitudes, a decrease solar energy occurs very slowly, and sharply increases in temperate and subpolar latitudes.

Unequal receipt solar heat at different latitudes affects the features of metabolic processes in the atmosphere and water shell Earth. It is now known that the global whirlpool of the World Ocean, driven by the wind, is additionally superimposed by the circulation "driven by the Sun". Thermohaline currents, the energy of which is directly determined by solar radiation, are less intense compared to wind turbines. Their speed, as a rule, does not exceed 10 cm/s, and drift currents - Brazilian, Somali, East Australian, etc. - move at a speed of 25-50 cm/s, and in some places 2-3 times faster.

Origin of thermohaline transfer ocean waters associated with education sea ​​ice at high latitudes. In the polar latitudes of both hemispheres with surface currents from the tropics, warm and salty water, which is cooled down to freezing temperature. Cold and dense under-ice waters gradually sink to the bottom and give rise to return flow towards the tropics. Approaching the zone of equatorial upwelling, deep Antarctic or Arctic waters rise to the surface in order to repeat their path to high latitudes again.

Other geographic implications are related to the size of the Earth. The mass of the Earth, creating a magnitude of attraction, prevents scattering atmospheric air into space and at the same time affects its gas composition(Earth has a stable and guaranteed oxygen-nitrogen atmosphere), He and H turn out to be candidates for “departure”.

The atmosphere regulates the incoming and outgoing part of thermal energy, its ozone shield protects living organisms from the harmful effects of excess ultraviolet rays. Don't be an atmosphere mean annual temperature would drop on the continents to -23.6 0 C and oceans to -20 0 C instead of +14.4 and +17.4 0C at present.

The size and mass of the Earth predetermine such a force gravity, which holds the atmosphere of a certain composition and the hydrosphere, without which life based on organic polymers would be impossible. The distance of the Earth from the Sun is also important. With a closer position of the Earth to the Sun than now, it could turn into a hot desert, with a more distant position, it could acquire a permanent ice shell. The scale of the processes taking place on the planet, as well as the range of natural zones depend on the size of the Earth: with larger sizes it would be richer and more diverse, with smaller ones it would be much poorer than it is now. Thus, life on Earth, the emergence and existence on it geographical envelope largely depend on the shape and size of our planet, as well as its distance from the Sun.

Geographic Consequences annual movement Earth.

At a speed of almost 30 km / s, our planet moves in an elliptical orbit around the Sun. The passage of the Earth through aphelion and through perihelion falls on the summer and winter time, which means that the orbital speed of the planet is higher in the winter and less in the summer half of the year in the northern hemisphere. The winter half-year in this case will last 179, and the summer half-year - 186 days.

The main movements of the Earth are the annual movement in orbit around the Sun and diurnal rotation around the axis. The first ensures the annual seasonality in all areas of the geographic envelope, the second - the change of day and night and the daily rhythm of the spheres.

1. Which statement about the geographical position of Russia is true?

1) In the southwest it borders on Ukraine
2) The extreme northern point of the country is located on the Yamal Peninsula
3) The area of ​​the country's territory exceeds 20 million square meters. km.
4) Russia is washed by the seas of four oceans
2. Which statement about the geographical position of Russia is true?
1) the length of the territory from north to south exceeds 10 thousand km
2) Russia is not washed by the seas of the Atlantic Ocean.
3) Far North mainland point country is Cape Dezhnev
4) Part of the territory of Russia is located in the Western Hemisphere.

Please write a plan for describing the geographical position of the mainland South America 1.) Determine how the mainland is located relative to the equator,

tropics and prime meridian. 2.) Determine the extreme points of the mainland, determine their coordinates and the length of the mainland in degrees and kilometers from north to south and from west to east. 3.) In what climatic zones is the mainland located? 4.) Determine which oceans and seas wash the mainland. 5.) How is the mainland relative to other continents?

Compare the geographical position of Africa and Australia. Determine the similarities and differences between the main components of the nature of the continents.

Plan:
1 Geographic location
2 Why geographical position continents is different
3 Natural areas
4 Why natural areas differ

The geographical position of mainland Australia 1) Determine how the mainland is located relative to the equator, the tropics (polar circles) and zero

meridian.

2) Find the extreme points of the mainland, determine their coordinates and the length of the mainland in degrees and kilometers from north to south and from west to east.

3) In what climatic zones is the mainland located?

4) Determine which oceans and seas wash the mainland.

5) How is the mainland relative to the two continents?

HELP YOU ANSWER THE QUESTIONS!

Plan for describing the geographical position of the mainland. Australia!!!

1. Position relative to conditional lines on the map: equator, tropics, polar circles, poles, zero meridian, 180th meridian.
2. Position in the hemispheres of the Earth.
3. Title extreme points mainland and their coordinates.
4. The length of the mainland from north to south in degrees and kilometers. The meridian along which the mainland has the greatest extent.
5. The length of the mainland from west to east in degrees and kilometers. The parallel along which the mainland has the greatest extent.
6. The position of the mainland in climatic zones and regions of climate.
7. The position of the mainland relative to the seas and oceans surrounding it.
8. The position of the mainland relative to other continents of the Earth.

I recently went on a one-day weekend excursion - I got a lot of pleasure and an object lesson on how location affects on mood and possible risks. We were standing at an old house, listening to a story about the history of the building, and people were standing by the road behind our backs, waiting for a green signal. One young couple, or rather, the wife, apparently already losing patience, spoke too loudly, because it became the property of everyone: “Yes, move away from the edge, you see a puddle over there. Some moron will drive over it at speed and pour over you! The man did not give up, even took a step closer to the edge. And then, to the pleasure of his wife, to the delight of the surrounding children, the same stupid driver arrived. The stubborn man was doused with dirty water almost to the head.

Geographic location of the continents

What is geographical location mainland? And this is his coordinates on the globe. And not just, but relative to the equator, parallels and meridians, as well as thermal zones, seas and oceans, other continents, and the like. Why is this knowledge needed? Actually, they give almost exhaustive information about the following points:

• about the climate;
• about flora and fauna;
• about possible cultural characteristics population;
• about politics and economics;
• and other.

Consequences of the GP of the continents in different latitudes

To know the consequences, you first need to understand what latitude is. And breadth is not the scope of arms, but coordinate of the continent relative to the equator and conditionally measured in degrees, but shown on parallels. Since latitude indicates position relative to the equator, one of the main consequences of a change in latitude is climatic features . That is, the lower the degrees of latitude to the equator, the warmer the climate on the mainland. Accordingly, the further - the colder. The maximum latitude is + 90° at the North Pole and - 90° at the South Pole.

The second consequence is the position coordinate − in the northern or southern hemisphere the mainland is located. You ask: "Is there a difference between the similar coordinates of the northern and southern hemispheres?". There is. And in what - this is another, voluminous question.

Topic 1 Introduction

Section 2 SOUTHERN CONTAINERS

1. Short story discoveries and research.

2. Geographic location, dimensions and configuration.

3. The history of the formation of nature.

1. The group of southern continents includes South America, Africa, Australia, having many common features of nature due to the similarity of their geographical location and the associated history of formation as part of Gondwana. Special place takes Antarctica. This continent is entirely located in southern hemisphere and is also part of the disintegrated Gondwana, but the special geographical position of the continent determines many of the unique features of its nature.

Earlier than others Southern continents the Europeans knew Africa. Inhabitants European states since ancient times different purposes visited its Mediterranean outskirts, in connection with which gradually accumulated various information about the nature and population of this region. Navigators circumnavigated the African continent as early as the 15th century, Arab trade caravans had crossed the Sahara before that, but the interior of the mainland long time remained unknown to Europeans. Only a few expeditions penetrated into the interior of Africa, mainly along major rivers. In the 19th century, when the countries of Europe needed new lands and Natural resources for the development of the economy, the territory of Africa was colonized, and its intensive study began. English and French travelers played an important role, but researchers from many countries participated in the discovery and exploration of the interior of the mainland: Germans, Belgians, Portuguese, Dutch, Russians, British, etc. The names of J. Speke and R.F. Burton, who discovered the Great African Lakes, D. Livingston and G.M. Stanley, who explored the territories along the major rivers - the Zambezi, the Congo. V.V. Juncker collected a huge amount of material characterizing the nature of the North and Central Africa. Now the nature of the majority African countries well studied, identified and used natural resources. A comprehensive study of the territory of the continent continues by scientists around the world.

About existence South America Europeans learned after the expedition of H. Columbus at the end of the 15th century. During the XV century. Spanish and Portuguese navigators explored the coast and penetrated deep into the mainland in search of treasure. Indian peoples, who inhabited South America at that time, were conquered, partially exterminated or driven out of their lands by the conquerors. The slave-owning state of the Incas, which had a highly developed culture for its time, was defeated. Already in the XVI - XVII centuries. the territory of the mainland turned into colonies of Spain and Portugal.

The study of the nature of the South American continent began in the 17th - 18th centuries. scientists different countries. The largest studies were in the XVIII century. expedition of the Paris Academy, and in the XIX century. five-year expedition led by A. Humboldt and E. Bonpland. Now the entire mainland has been studied to one degree or another, but in the remote areas of the Guiana Highlands, the Amazon, the Andes, there are still places where no man has set foot, except for very few tribes of Indians, whose life is practically unknown to us. At present, aerial and satellite surveys of the entire territory of the mainland have been made, but many details of the structure of the surface are hidden by dense vegetation of tropical rainforests.

The first uncertain information about the existence australia reached Europe through Portuguese navigators, who apparently visited the northern coast of the mainland as early as the 16th century. However, the discovery of Australia is attributed to 1606, when the Dutch-Spaniards documented a visit to the Cape York Peninsula. In the 17th century a number of Dutch expeditions explored the shores of the continent, which they called New Holland. After the voyage of J. Cook, who visited the mainland in 1770, the British founded a penal colony in the area of ​​\u200b\u200bmodern Sydney (1788) and began systematic exploration of both the coasts and subsequently the interior of the mainland. In the 19th century following the English explorers in Australia traveled with scientific purposes and the French, and the Germans, and the Poles. The survey of the interior of the continent ended with British expeditions late XIX- the beginning of the twentieth century. By this time, the territory of Australia was practically mastered by Great Britain, first as a place of exile for criminals, then as a colony inhabited by emigrants who displaced indigenous people in barren and arid regions. The territory of the mainland is well studied in all respects.

The least explored continent on Earth Antarctica. severe weather in the Antarctic regions, ice covering coastal waters for most of the year, and often all year round, for a long time did not allow sailors to approach the shores of the continent. To early XIX in. only a few island archipelagos of Antarctica have been discovered. In 1820, a Russian expedition led by F. Bellingshausen and M. Lazarev discovered the ice shores of the mainland. People first landed on the coastal rocks in the 30s, and ashore - only in the 90s. 19th century The study of the coast began in the early years of the 20th century; travelers penetrated deep into the mainland in 1911, when the expeditions of the Norwegian R. Amundsen and the Englishman R. Scott almost simultaneously reached South Pole. In the 20-30s. 20th century the icy continent was surveyed by scientists from a number of countries from aircraft and sledge trips. In the 40-50s. in the Antarctic, a network of ground stations and bases was created, and in the period of preparation for the International Geophysical Year (since 1955), 11 countries deployed 57 bases and points from which research work. Until now, scientific stations and bases of many states have been operating on the mainland, conducting research according to agreed programs. However, the area has not been fully explored. In 1959, the International Treaty on Antarctica was concluded, according to which its legal regime was determined. According to this agreement, the entire territory of Antarctica is a demilitarized zone. Within its limits it is allowed to conduct free Scientific research with the exchange of information and data on plans and results of work.

2. The geographical position of the southern continents has common features, which significantly affect the similarity of their basic natural properties.

Significant areas within Africa, South America and Australia are located at low latitudes, due to which they receive a large number of heat. These three continents are often referred to as the Southern Tropical Continents. It is also significant that the arrival solar radiation in these latitudes, relatively little changes during the year.

· The southern continents are relatively little connected with each other and with other continents. Only Africa has in the northeast quite close relations with Eurasia. South America has a connection with North only through the narrow mountainous Central American Isthmus, Australia has existed in isolation since the middle of the Mesozoic. Antarctica is surrounded on all sides by ocean. Between the continents, the exchange of elements of flora and fauna is currently difficult, and only the organic world of the Sahara region of Africa has many features in common with the Arabian Peninsula, and the Atlas region with the Eurasian Mediterranean.

Africa, South America and Australia are more or less equally located in relation to their surrounding oceans with similar current systems: western shores all three continents are washed in equatorial latitudes by warm currents, and in tropical and subtropical latitudes by predominantly cold currents; the east coasts are mainly affected warm currents; from the south, all the southern continents are washed by a powerful cold current Western winds, which has a significant impact on the properties of their nature. The existence of this current largely determines the natural features of Antarctica.

There are significant differences that are important for the formation of individual natural features every continent.

· South America is further pushed into high latitudes than other South Tropical continents. Its southern tip is located within the temperate climate zone. On the territory of the continent, the most diverse set geographical areas. The mainland is washed from the west by water Pacific Ocean with a powerful cold Peruvian current, penetrating along the coast far to the north - into equatorial latitudes. The continent has the greatest width in equatorial latitudes.

· Africa is located symmetrically with respect to the equator: its extreme northern and southern points are almost at the same latitude. The mainland is washed from the north mediterranean sea, whose influence affects the northern margin of the continent. Africa neighbors and is closely connected with Eurasia and has common features with the subcontinent Southwest Asia. It is the only one of the southern continents most of which is located in the Northern Hemisphere.

· Australia lies entirely in the Southern Hemisphere, entering subtropical latitudes in the south. The mainland is washed from the north by warm Australo-Asian seas. The influence of the Pacific Ocean is somewhat weakened whole system island arcs bordering the continent from the east. Australia is the most isolated of all the South Tropical continents, which primarily affects the originality organic world within it.

The unique polar position of Antarctica predetermines the low heat input to its territory, the specific features of the nature of this continent are directly or indirectly related to the circumpolar location of a large continental mass and its complete insulation from other land areas.

By size all the southern continents are inferior to Eurasia. Even the largest of them - Africa is almost half the size of Eurasia in area.

Configuration Africa, South America and, to a lesser extent, Australia follow patterns that are to some extent inherent in all the continents of the Earth: they are wide in the northern part, they narrow towards the south, and they are widest in low latitudes. On the Southern Tropical Continents, landscapes of the equatorial-tropical belts occupy 85% of the territory (on northern continents- about 20%).

The southern continents have significantly fewer protrusions in their outlines than the northern ones (area ratio major peninsulas and the core of the continent for Eurasia and North America is 1:3, South America - 1:50, for Africa - 1:99, in Australia this ratio is close to the North - 1:4, but at the expense of large peninsulas).

All of these features are involved in the formation of specific features of the nature of the southern continents.

? – In what parameters are the Southern continents similar to each other, in what ways do they differ the most from each other?

- What features of nature can be associated with the geographical location, size and configuration of each of the southern continents? Which of these factors determine the similarities in the nature of the Southern continents? What are the features of the difference?