Our planet is constantly in the gravitational field created by the Moon and the Sun. This is the reason unique phenomenon, expressed in tides on the Earth. Let's try to figure out whether these processes affect environment and human life.
The mechanism of the phenomenon of "ebb and flow"
The nature of the formation of ebbs and flows has already been sufficiently studied. Over the years, scientists have investigated the causes and results of this phenomenon.
Similar fluctuations in the level of terrestrial waters can be shown in the following system:
- The water level gradually rises, reaching its highest point. This phenomenon is called full water.
- After a certain period of time, the water begins to subside. This process scientists gave definition of "ebb".
- For about six hours, the water continues to go to its minimum point. Such a change was called in the form of the term "low water".
You can notice some regularity if you observe the process of the tide in the same place for a month. The results of the analysis are interesting: daily low and high water changes its location. With such natural factor like education new moon and the full moon, the levels of the studied objects move away from each other.
Consequently, this makes twice a month the amplitude of the tide to the maximum. The appearance of the smallest amplitude also periodically occurs, when, after the characteristic influence of the Moon, the levels of low and high waters gradually approach each other.
Causes of high and low tides on Earth
There are two factors that influence the formation of tides. Both objects that affect the change in the Earth's water space should be carefully considered.
The effect of lunar energy on the ebb and flow
Although the influence of the Sun on the cause of the tides is undeniable, but still highest value in this matter belongs to the influence of lunar activity. In order to feel the significant impact of the satellite's gravity on our planet, it is necessary to follow the difference in the attraction of the Moon in different areas Earth.
The results of the experiment will show that the difference in their parameters is rather small. The thing is that the point closest to the moon earth's surface exposed external influence literally 6% more than the most remote. It can be said with certainty that this separation of forces pushes the Earth apart in the direction of the Moon-Earth trajectory.
Taking into account the fact that our planet constantly turns around its axis during the day, a double tidal wave passes twice along the perimeter of the created stretch. This is accompanied by the creation of the so-called double "valleys", the height of which, in principle, does not exceed 2 meters in the oceans.
On the territory of the earth's land, such fluctuations reach a maximum of 40-43 centimeters, which in most cases goes unnoticed by the inhabitants of our planet.
All this leads to the fact that we do not feel the power of the ebb and flow, either on land or in water element. A similar phenomenon can be observed on a narrow strip coastline, because the waters of the ocean or the sea, by inertia, sometimes gain an impressive height.
From all that has been said, we can conclude that the ebbs and flows are most associated with the Moon. This makes research in this area the most interesting and relevant.
The influence of the activity of the Sun on the ebbs and flows
The significant remoteness of the main star of the solar system from our planet affects the fact that its gravitational effect is less noticeable. As a source of energy, the Sun is certainly much more massive than the Moon, but still makes itself felt by the impressive distance between the two celestial objects. The amplitude of solar tides is almost half that of the tidal processes of the Earth's satellite.
A well-known fact is that during the full moon and the growth of the moon, all three celestial bodies a - the Earth, the Moon and the Sun - are located on one straight line. This leads to the folding of the lunar and solar tides.
During the period of direction from our planet to its satellite and main star The solar system, which differs from each other by 90 degrees, there is some influence of the Sun on the process under study. There is an increase in the level of low tide and a decrease in the level of the tide of terrestrial waters.
Everything indicates that solar Activity also affects the energy of the tides on the surface of our planet.
The main types of ebbs and flows
It is possible to classify such a concept by the duration of the tide cycle. The demarcation will be fixed with the following points:
- Semidiurnal changes in the surface of the water. Such transformations consist in two full and the same number of incomplete waters. The parameters of alternating amplitudes are almost equal to each other and look like a sinusoidal curve. Most of all they are localized in the waters Barents Sea, on a broad line coastal strip White Sea and throughout almost all Atlantic Ocean.
- Daily fluctuations in water level. Their process consists in one full and incomplete water for a period calculated within a day. A similar phenomenon is observed in the region Pacific Ocean, and its formation is extremely rare. During the passage of the Earth's satellite through equatorial zone the effect of standing water is possible. If the Moon is declining with the least indicator, small equatorial tides occur. At the highest numbers, the process of formation of tropical tides occurs, accompanied by the greatest power of water inflow.
- tides mixed type . This concept includes the presence of irregular semidiurnal and diurnal tides. Semidiurnal changes in the level of the earth's water shell, which have an irregular configuration, are similar in many ways to semidiurnal tides. In altered diurnal tides, one can observe a tendency to diurnal fluctuations, depending on the degree of declination of the moon. The most affected by mixed tides are the waters of the Pacific Ocean.
- anomalous tides. These rises and falls of water do not fit the description of some of the signs listed above. This anomaly is associated with the concept of "shallow water", which changes the cycle of rise and fall of the water level. The influence of this process is especially pronounced in the mouths of the rivers, where the tides are shorter in time than the tides. You can observe a similar cataclysm in some parts of the English Channel and in the currents of the White Sea.
Ebb and flow chart on Earth
There is a so-called tide table. It is necessary for people who, by the nature of their activities, depend on changes in the earth's water level. To have accurate information on this phenomenon, you need to pay attention to:
- Designation of an area where it is important to know the tide data. It is worth remembering that even closely spaced objects will have different characteristics phenomenon of interest.
- Finding necessary information using Internet resources. For more accurate information you can visit the port of the region under study.
- Specifying the timing of the need for accurate data. This aspect depends on whether the information is needed for a certain day or the study schedule is more flexible.
- Work with the table in the mode of emerging needs. It will display all the tide and tide information.
- The columns at the top of the table indicate the days and dates of the alleged occurrence. This item will allow you to find out the point of determining the time frame of the study.
- Under the line of temporary accounting are figures placed in two rows. In the format of the day, the decoding of the phases of the rising of the Moon and the Sun is placed here.
- Below is a waveform chart. These indicators fix the peaks (tides) and depressions (low tides) of the waters of the study area.
- After calculating the amplitude of the waves, the data of the entry of celestial bodies are located, which affect changes in the water shell of the Earth. This aspect will allow you to observe the activity of the Moon and the Sun.
- On both sides of the table you can see numbers with plus and minus indicators. This analysis is important for determining the level of rise or fall of water, calculated in meters.
All these indicators cannot guarantee one hundred percent information, because nature itself dictates to us the parameters by which its structural changes occur.
The effect of tides on the environment and humans
There are many factors influencing the ebb and flow of tides on human life and the environment. Among them are discoveries of a phenomenal nature that require careful study.
Killer waves: hypotheses and consequences of the phenomenon
This phenomenon causes a lot of controversy among people who trust only unconditional facts. The fact is that stray waves do not fit into any system of occurrence of this phenomenon.
Study of this object made possible with the help of radar format satellites. These designs made it possible to record a dozen waves of ultra-large amplitude over a period of a couple of weeks. The size of such a rise of a water block is about 25 meters, which indicates the grandeur of the phenomenon under study.
Killer waves directly affect human life, because for recent decades such anomalies carried huge ships such as supertankers and container ships into the ocean depths. The nature of the formation of this stunning paradox is unknown: giant waves formed instantly and also quickly disappear.
There are many hypotheses regarding the cause of the formation of such a whim of nature, but the occurrence of whirlpools (single waves due to the collision of two solitons) is possible with the intervention of the activity of the Sun and the Moon. This question still becomes a reason for discussion among scientists specializing in this topic.
The influence of ebbs and flows on the organisms that inhabit the Earth
The tides in the ocean and sea especially affect marine life. This phenomenon exerts the greatest pressure on the inhabitants of coastal waters. Thanks to this change level earth water organisms leading a sedentary lifestyle develop.
These include mollusks, which have perfectly adapted to fluctuations in the liquid shell of the Earth. Oysters at the highest tides begin to actively multiply, which indicates that they respond favorably to such changes in the structure of the water element.
But not all organisms react so favorably to external changes. Many species of living beings suffer from periodic fluctuations in water levels.
Although nature takes its toll and coordinates changes in general balance sheet planets, but biological substances adapt to the conditions that the activity of the Moon and the Sun presents them with.
The impact of ebbs and flows on human life
On the general state human this phenomenon affects more than the phases of the moon, to which the human body may be immune. However, the most ebbs and flows affect the production activities of the inhabitants of our planet. It is unrealistic to influence the structure and energy of the tides of the sea, as well as the oceanic sphere, because their nature depends on the gravity of the Sun and the Moon.
Basically, this cyclical phenomenon brings only destruction and trouble. Modern technologies allow this negative factor steer in a positive direction.
An example of such innovative solutions pools can serve as traps for such fluctuations water balance. They must be built to be cost-effective and practical.
To do this, it is necessary to create such pools of a fairly significant size and volume. Tidal force containment power plants water resources Earth is a new business, but quite promising.
Watch the video about the ebb and flow:
The study of the concept of tides on Earth, their influence on life cycle planets, the mystery of the origin of killer waves - all this remains the main questions for scientists specializing in this field. The solution of these aspects is also interesting for ordinary people who are interested in the problems of the influence of foreign factors on the planet Earth.
There is a rise and fall of water. This phenomenon sea tides and ebbs. Already in antiquity, observers noticed that the tide comes some time after the culmination of the Moon at the place of observation. Moreover, the tides are strongest on the days of new and full moons, when the centers of the Moon and the Sun are approximately on the same straight line.
Given this, I. Newton explained the tides by the action of gravity from the Moon and the Sun, namely, that different parts of the Earth are attracted by the Moon in different ways.
The Earth rotates on its axis much faster than the Moon revolves around the Earth. As a result, the tidal hump (the relative position of the Earth and the Moon is shown in Figure 38) moves, a tidal wave runs along the Earth, and tidal currents arise. When approaching the shore, the height of the wave increases as the bottom rises. In inland seas the height of the tidal wave is only a few centimeters, in open ocean reaches about one meter. In favorably located narrow bays the height of the tide increases several times more.
Friction of water on the bottom, as well as deformation hard shell Earths are accompanied by the release of heat, which leads to the dissipation of the energy of the Earth-Moon system. Since the tidal hump is due east, the maximum tide occurs after the Moon's culmination, the pull of the hump causes the Moon to accelerate and the Earth's rotation to slow. The moon is gradually moving away from the earth. Indeed, geological data show that jurassic(190-130 million years ago), the tides would be much higher, and the day would be shorter. It should be noted that when the distance to the Moon decreases by a factor of 2, the height of the tide increases by a factor of 8. Currently, the day is increasing by 0.00017 s per year. So in about 1.5 billion years their length will increase to 40 modern days. The month will be the same length. As a result, the Earth and the Moon will always face each other with the same side. After that, the Moon will gradually begin to approach the Earth and in another 2-3 billion years it will be torn apart by tidal forces (if, of course, by that time the Solar system will still exist).
The influence of the moon on the tide
Consider, following Newton, in more detail the tides caused by the attraction of the Moon, since the influence of the Sun is significantly (2.2 times) less.
Let us write down the expressions for the accelerations caused by the attraction of the Moon for different points Earth, given that for all bodies at a given point in space, these accelerations are the same. AT inertial system reference connected to the center of mass of the system, the acceleration values will be:
A A \u003d -GM / (R - r) 2, a B \u003d GM / (R + r) 2, a O \u003d -GM / R 2,
where a A, aO, a B are the accelerations caused by the attraction of the Moon at the points A, O, B(Fig. 37); M is the mass of the moon; r is the radius of the Earth; R- the distance between the centers of the Earth and the Moon (for calculations, it can be taken equal to 60 r); G is the gravitational constant.
But we live on the Earth and all observations are carried out in a reference system associated with the center of the Earth, and not with the Earth-Moon center of mass. To pass to this system, it is necessary to subtract the acceleration of the center of the Earth from all accelerations. Then
A’ A = -GM ☾ / (R - r) 2 + GM ☾ / R 2 , a’ B = -GM ☾ / (R + r) 2 + GM / R 2 .
Let's do the parentheses and take into account that r little compared to R and can be neglected in sums and differences. Then
A’ A \u003d -GM / (R - r) 2 + GM ☾ / R 2 \u003d GM ☾ (-2Rr + r 2) / R 2 (R - r) 2 \u003d -2GM ☾ r / R 3.
Accelerations a’A and a’B identical in modulus, opposite in direction, each directed from the center of the Earth. They're called tidal accelerations. At points C and D tidal accelerations, smaller in magnitude and directed towards the center of the Earth.
Tidal accelerations are called accelerations arising in the frame of reference associated with the body due to the fact that, due to the finite dimensions of this body, its different parts are attracted differently by the perturbing body. At points A and B the acceleration of gravity is less than at the points C and D(Fig. 37). Therefore, in order for the pressure at the same depth to be the same (as in communicating vessels) at these points, the water must rise, forming the so-called tidal hump. The calculation shows that the rise of water or the tide in the open ocean is about 40 cm. In coastal waters it is much larger, and the record is about 18 m. The Newtonian theory cannot explain this.
On the coast of many outer seas one can see a curious picture: fishing nets are stretched along the coast not far from the water. Moreover, these nets were set up not for drying, but for catching fish. If you stay on the shore and watch the sea, then everything will become clear. Now the water begins to rise, and where only a few hours ago there was a sandbank, waves splashed. When the water receded, nets appeared in which the entangled fish sparkled with scales. The fishermen, bypassing the nets, took off the catch. material from the site
Here is how an eyewitness describes the onset of the tide: “We got to the sea,” a fellow traveler told me. I looked around in bewilderment. There really was a shore in front of me: a trail of ripples, a half-buried skeleton of a seal, rare pieces of a fin, fragments of shells. And beyond that stretched a flat expanse... and no sea. But three hours later, the motionless line of the horizon began to breathe, became agitated. And now the sea swell sparkled behind her. A wave of tide rolled uncontrollably forward across the gray surface. Overtaking each other, the waves ran ashore. One after another, distant rocks sank - and all around you can see only water. She throws salt spray in my face. Instead of a dead plain, the water surface lives and breathes in front of me.
When a tidal wave enters a funnel-shaped bay, the shores of the bay seem to compress it, which is why the height of the tide increases several times. So, in the Bay of Fundy east coast North America the tide reaches 18 m. In Europe, the most high tides(up to 13.5 meters) are in Brittany near the city of Saint-Malo.
Very often, a tidal wave enters the mouths of rivers, raising the water level in them by several meters. For example, near London, at the mouth of the River Thames, the tide is 5 m high.
In order to exhaust the main questions related to the existence of its satellite near the Earth - the Moon, we need to say a few words about the phenomenon of tides. This is also necessary in order to receive a response to last question raised in this book: where did the moon come from and what is its future? What is a tide?
During high tides on the shores of the open seas and oceans, water advances onto the shores. The low banks are literally overwhelmed by huge masses of water. Huge spaces are covered with water. The sea, as it were, protrudes from the shores and presses onto the land. The sea water is clearly rising.
At high tides (64) ocean-going deep-water vessels are free to enter relatively shallow harbors and estuaries flowing into the oceans.
The tidal wave is very high in some places, reaching a dozen or more meters.
Approximately six hours pass from the beginning of the rise of the water, and the tide is replaced by an ebb (65), the water begins to gradually
subside, the sea near the coast becomes shallow, and significant areas of the coastal strip are freed from water. Recently, steamboats sailed in these places, and now residents roam the wet sand and gravel and collect shells, algae and other "gifts" of the sea.
What explains these constant ebb and flow? They occur due to the attraction that the Moon exerts on the Earth.
Not only does the Earth pull the Moon towards itself, but the Moon also pulls the Earth. The gravity of the Earth affects the motion of the Moon, causing the Moon to move along a curved path. But at the same time, the attraction of the Earth somewhat changes the shape of the Moon. The parts facing the Earth are attracted by the Earth more strongly than other parts. Thus, the Moon should have a somewhat elongated shape towards the Earth.
The attraction of the moon also affects the shape of the earth. On the side facing this moment to the Moon, there is some swelling, stretching of the earth's surface (66).
The particles of water, being more mobile and having little cohesion, are more amenable to this attraction of the Moon than particles of solid land. In this regard, a very noticeable rise in water in the oceans is created.
If the Earth, like the Moon, were always facing the Moon with the same side, its shape would be somewhat elongated towards the Moon, and there would be no alternating tides. But the earth is turning different sides to all heavenly bodies, including to the Moon ( diurnal rotation). In this regard, a tidal wave, as it were, runs along the Earth, runs after the Moon, which raises the water of the oceans higher in the parts of the earth's surface facing it at the moment. High tides should alternate with low tides.
In a day, the Earth will make one rotation around its axis. Consequently, exactly one day later, the same parts of the earth's surface should face the Moon. But we know that the Moon manages to cover some part of its path around the Earth in a day, moving in the same direction as the Earth rotates. Therefore, the period is lengthened, after which the same parts of the Earth will be turned to the Moon. Thereby The cycle of ebb and flow does not occur in a day, but in 24 hours and 51 minutes. During this period of time, two high tides and two low tides alternate on Earth.
But why two and not one? We find an explanation for this by recalling once again the law gravity. According to this law, the force of attraction decreases with increasing distance, and, moreover, inversely proportional to its square: the distance doubles - the attraction decreases four times.
On the side of the Earth, directly opposite that which faces the Moon, the following occurs. Particles close to Earth's surface, are attracted by the Moon weaker than the inner parts of the Earth. They tend less towards the Moon than particles closer to it. Therefore, the surface of the seas here, as it were, lags somewhat behind solid internal parts of the globe and here it also turns out the rise of water, a water hump, a tidal prominence, approximately the same as on opposite side. Here, too, the tidal wave runs into the low shores. Consequently, there will be a tide along the coasts of the oceans both when these coasts are turned towards the Moon, and when the Moon is in the opposite direction. Thus, on Earth there must be two high tides and two low tides per period full turn Earth around the axis.
Of course, the magnitude of the tide is also influenced by the attraction of the Sun. But although the Sun is colossal in size, it is, however, much further from the Earth than the Moon. Its tidal influence is less than the influence of the Moon by half (only 5/11 or 0.45 of the tidal influence of the Moon).
The magnitude of each tide also depends on the height at which it is in given time Moon. At the same time, it is completely indifferent what phase the Moon has at this time and whether it is visible in the sky. The moon may not be visible at this moment, that is, it may be in the same direction as the sun, and vice versa. Only in the first case, the tide will generally be stronger than usual, since the attraction of the Sun is added to the attraction of the Moon.
The calculation shows that the tidal force of the Moon is only one nine-millionth of the force of gravity on Earth, that is, the force with which the Earth itself attracts. Of course, this attractive action of the Moon is negligible. The rise of water by several meters is also negligible in comparison with the equatorial diameter of the globe, equal to 12,756,776 m. But a tidal wave, even such a small one, is, as we know, very noticeable for the inhabitants of the Earth located near the coast of the oceans.
Who wouldn't want to take a walk to the bottom of the sea? "It's impossible! - you will exclaim. “For this you need at least a caisson!” But don't you know that twice a day they open for viewing large spaces seabed? True, woe to anyone who decides to stay at this "exhibition" beyond the set time! The seabed opens up at low tide. is a change of high and low water.
This is one of the mysteries of nature. Many naturalists tried to solve it: Kepler who discovered the law of planetary motion, newton who established the basic laws of motion, French scientist Laplace who studied the formation of celestial bodies. They all wanted to penetrate the secrets of the life of the oceans..
The wind creates waves on the sea. But to control the ebb and flow, the wind is too weak. Even a storm can only be a helper at high tide. What gigantic forces do such hard work?
The influence of the moon on the ebb and flow
Three giants are fighting for the oceans: Sun, Moon and Earth itself. The sun is the strongest, but it is too far away from us to be the winner. The movement of masses of water on Earth is controlled mainly by the Moon. Being at a distance of 384,000 kilometers from the Earth, it regulates the "pulse" of the oceans. Like a huge magnet, the Moon pulls masses of water up several meters, while the Earth rotates around its axis.
Although the difference between the height of the tide and the low tide is on average no more than 4 meters, the work that the Moon does is enormous. It is equal to 11 trillion horsepower. If this number is written in one number, then it will have 18 zeros and look like this: 11,000,000,000,000,000,000. You cannot collect such a number of horses, even if you drive herds from all the "ends" of the globe.
Ebb and flow - sources of energy
After the Sun ebbs and flows- The biggest energy sources. They could give electricity around the world. Since time immemorial, man has tried to make the moon serve him. In China and other countries, tidal waters have long turned millstones.
In 1913, the first "lunar" energy station was put into operation in the North Sea near Husum. In England, France, the USA, and especially in Argentina, which feels a shortage of fuel, many bold projects for the construction of tide stations have been created. However, they went further Soviet engineers who created a project for the construction of a dam 100 kilometers long and 15 meters high in the Mezen Bay of the White Sea.
At high tide, a reservoir with a capacity of 2,000 square kilometers forms behind the dam. Two thousand turbogenerators will give 36 billion kilowatt-hours. This amount of energy was produced in 1929 by France, Italy and Switzerland combined. A kilowatt-hour of this energy will cost about one penny. Unfortunately, the "pulse" ebbs and flows of the sea beats with unequal force, like a human pulse. The tides do not provide a constant, uniform flow of water, and this makes the project difficult to carry out.
The tide is at its strongest when the sun and moon pull masses of water in the same direction. Tides where the water level rises up to 20 meters, occur at full and young moon. They are called "syzygy". In the first and last quarter months when the moon is at right angles to the sun, tides are at their lowest and are called quadrature.
The ebb and flow of the sea are very great importance for navigation, and therefore their offensive calculate in advance. This calculation is so difficult that it takes many weeks to compile an annual tide calendar. But the inventive mind of man created computer, whose “electronic brain” makes tide forecasts for two days. The tidal calendar shows that tidal waves move throughout the globe through certain intervals time. From sea shores they go up into the rivers.
Ebb and flow is the periodic rise and fall of the water level in the oceans and seas.
Twice during the day with an interval of about 12 hours 25 minutes the water near the ocean or high seas rises and, if there are no barriers, sometimes floods large spaces - this is a tide. Then the water goes down and recedes, exposing the bottom - this is the ebb. Why is this happening? Even ancient people thought about this, they noticed that these phenomena are associated with the moon. The main reason for the ebb and flow was first pointed out by I. Newton - this is the attraction of the Earth by the Moon, or rather, the difference between the attraction of the Moon of the entire Earth as a whole and its water shell.
Ebb and flow explained by Newton's theory
The attraction of the Earth by the Moon is made up of the attraction of the individual particles of the Earth by the Moon. Particles that are currently closer to the Moon are attracted by it more strongly, and more distant ones are weaker. If the Earth were absolutely solid, then this difference in the force of attraction would not play any role. But the earth is not absolutely solid, therefore, the difference in the attractive forces of particles located near the surface of the Earth and near its center (this difference is called the tide-forming force) displaces the particles relative to each other, and the Earth, primarily its water shell, is deformed.
As a result, on the side that faces the Moon, and on its opposite side, the water rises, forming tidal protrusions, and excess water accumulates there. Due to this, the water level in other opposite points The earth at this time is reduced - there is a low tide.
If the Earth did not rotate, and the Moon remained motionless, then the Earth, together with its water shell, would always retain the same elongated shape. But the Earth rotates, and the Moon moves around the Earth in about 24 hours and 50 minutes. With the same period, tidal protrusions follow the Moon and move along the surface of the oceans and seas from east to west. Since there are two such protrusions, a tidal wave passes over each point in the ocean twice a day with an interval of about 12 hours and 25 minutes.
Why is the height of the tidal wave different
In the open ocean, the water rises slightly during the passage of a tidal wave: about 1 m or less, which remains almost imperceptible to sailors. But off the coast, even such a rise in the water level is noticeable. In bays and narrow bays, the water level rises much higher during high tides, since the coast prevents the movement of the tidal wave and water accumulates here during the entire time between low tide and high tide.
The largest tide (about 18 m) is observed in one of the bays on the coast in Canada. In Russia, the highest tides (13 m) occur in the Gizhiginskaya and Penzhinskaya bays. Sea of Okhotsk. In inland seas (for example, in the Baltic or Black), the tides are almost imperceptible, because masses of water moving along with the ocean tidal wave do not have time to penetrate into such seas. But all the same, in every sea or even lake, independent tidal waves arise with a small mass of water. For example, the height of the tides in the Black Sea reaches only 10 cm.
In the same area, the height of the tide is different, since the distance from the Moon to the Earth and highest altitude The moons above the horizon change over time, and this leads to a change in the magnitude of tidal forces.
Tides and Sun
The sun also influences the tides. But the tidal forces of the Sun are 2.2 times less than the tidal forces of the Moon.
During the new moon and full moon, the tidal forces of the sun and moon act in the same direction - then the highest tides are obtained. But during the first and third quarters of the Moon, the tidal forces of the Sun and Moon counteract, so the tides are smaller.
Tides in the air shell of the Earth and in its solid body
Tidal phenomena occur not only in water, but also in air shell Earth. They are called atmospheric tides. Tides also occur in the solid body of the Earth, since the Earth is not absolutely solid. Vertical oscillations of the Earth's surface due to tides reach several tens of centimeters.
The practical use of ebb and flow
The tidal power plant is special kind hydroelectric power plants that use tidal energy, but in fact kinetic energy rotation of the earth. Tidal power plants are built on the shores of the seas, where gravitational forces The moon and the sun change the water level twice a day. Water level fluctuations near the coast can reach 18 meters.
In 1967, a tidal power station was built in France at the mouth of the Rance River.
In Russia, since 1968, an experimental TPP has been operating in Kislaya Bay on the coast of the Barents Sea.
There are PES and abroad - in France, Great Britain, Canada, China, India, the USA and other countries.
