Ebb and flow times of the day. Sea tides and tides. Why do tides vary in different places on Earth?

Ebb and flow
periodic fluctuations in the water level (ups and downs) in the water areas on the Earth, which are due to the gravitational attraction of the Moon and the Sun, acting on the rotating Earth. All large water areas, including oceans, seas and lakes, are subject to tides to one degree or another, although they are small on lakes. The highest water level observed in a day or half a day at high tide is called high tide, the lowest level at low tide is called low water, and the moment these limit marks are reached is called standing (or stage), respectively, high tide or low tide. The mean sea level is a conditional value, above which the level marks are located during high tides, and below - during low tides. This is the result of averaging large series of urgent observations. The average height of the tide (or low tide) is an average value calculated from a large series of data on the levels of high or low waters. Both of these middle levels are linked to the local stock. Vertical fluctuations in the water level during high and low tides are associated with horizontal movements of water masses in relation to the coast. These processes are complicated by wind surge, river runoff and other factors. Horizontal movements of water masses in the coastal zone are called tidal (or tidal) currents, while vertical fluctuations in the water level are called ebbs and flows. All phenomena associated with ebbs and flows are characterized by periodicity. Tidal currents periodically reverse direction, while ocean currents, moving continuously and unidirectionally, are due to the general circulation of the atmosphere and cover large expanses of the open ocean (see also OCEAN). During the transitional intervals from high tide to low tide and vice versa, it is difficult to establish the trend of the tidal current. At this time (not always coinciding with high or low tide) the water is said to "stagnate". High and low tides alternate cyclically in accordance with the changing astronomical, hydrological and meteorological conditions. The sequence of tidal phases is determined by two maxima and two minima in the daily course.
Explanation of the origin of tidal forces. Although the Sun plays a significant role in tidal processes, the decisive factor in their development is the force of the gravitational attraction of the Moon. The degree of influence of tidal forces on each particle of water, regardless of its location on the earth's surface, is determined by Newton's law of universal gravitation. This law states that two material particles are attracted to each other with a force that is directly proportional to the product of the masses of both particles and inversely proportional to the square of the distance between them. This implies that the greater the mass of bodies, the greater the force of mutual attraction between them (with the same density, a smaller body will create less attraction than a larger one). The law also means that the greater the distance between two bodies, the less the attraction between them. Since this force is inversely proportional to the square of the distance between two bodies, the distance factor plays a much larger role in determining the magnitude of the tidal force than the masses of the bodies. The gravitational attraction of the Earth, acting on the Moon and keeping it in near-Earth orbit, is opposite to the force of attraction of the Earth by the Moon, which tends to move the Earth towards the Moon and "lifts" all objects on the Earth in the direction of the Moon. The point on the earth's surface, located directly under the Moon, is only 6,400 km away from the center of the Earth and, on average, 386,063 km from the center of the Moon. In addition, the mass of the Earth is approximately 89 times the mass of the Moon. Thus, at this point on the earth's surface, the attraction of the Earth, acting on any object, is approximately 300 thousand times greater than the attraction of the Moon. It is a common notion that water on Earth, directly under the Moon, rises in the direction of the Moon, causing water to flow away from other places on the Earth's surface, but since the Moon's pull is so small compared to Earth's, it would not be enough to lift such huge weight. However, the oceans, seas, and large lakes on Earth, being large fluid bodies, are free to move under the force of lateral displacement, and any slight horizontal shear tendency sets them in motion. All waters that are not directly under the Moon are subject to the action of the component of the Moon's gravitational force directed tangentially (tangentially) to the earth's surface, as well as its component directed outward, and are subject to horizontal displacement relative to the solid earth's crust. As a result, there is a flow of water from the adjacent regions of the earth's surface towards a place under the moon. The resulting accumulation of water at a point under the Moon forms a tide there. The actual tidal wave in the open ocean has a height of only 30-60 cm, but it increases significantly when approaching the shores of continents or islands. Due to the movement of water from neighboring regions towards a point under the Moon, corresponding outflows of water occur at two other points remote from it at a distance equal to a quarter of the circumference of the Earth. It is interesting to note that the lowering of the ocean level at these two points is accompanied by a rise in the sea level not only on the side of the Earth facing the Moon, but also on the opposite side. This fact is also explained by Newton's law. Two or more objects located at different distances from the same source of gravity and, therefore, subjected to acceleration of gravity of different magnitudes, move relative to each other, since the object closest to the center of gravity is most strongly attracted to it. Water at a sublunar point experiences a stronger attraction to the Moon than the Earth below it, but the Earth, in turn, is more strongly attracted to the Moon than water on the opposite side of the planet. Thus, a tidal wave arises, which on the side of the Earth facing the Moon is called direct, and on the opposite side it is called reverse. The first of them is only 5% higher than the second. Due to the rotation of the Moon in its orbit around the Earth, approximately 12 hours and 25 minutes pass between two successive high tides or two low tides in a given place. The interval between the climaxes of successive high and low tides is approx. 6 h 12 min. The period of 24 hours and 50 minutes between two successive high tides is called a tidal (or lunar) day.
Tide inequalities. Tidal processes are very complex, so many factors must be taken into account in order to understand them. In any case, the main features will be determined by: 1) the stage of tide development relative to the passage of the Moon; 2) the amplitude of the tide; and 3) the type of tidal fluctuation, or the shape of the water level curve. Numerous variations in the direction and magnitude of tidal forces give rise to differences in the magnitudes of morning and evening tides in a given port, as well as between the same tides in different ports. These differences are called tide inequalities.
semi-permanent effect. Usually during the day, due to the main tidal force - the rotation of the Earth around its axis - two complete tidal cycles are formed. When viewed from the North Pole of the ecliptic, it is obvious that the Moon rotates around the Earth in the same direction in which the Earth rotates around its axis - counterclockwise. With each subsequent revolution, this point on the earth's surface again takes a position directly under the Moon, somewhat later than during the previous revolution. For this reason, both high and low tides are late every day by about 50 minutes. This value is called the lunar delay.
Semi-monthly inequality. This main type of variation is characterized by a periodicity of approximately 143/4 days, which is associated with the rotation of the Moon around the Earth and the passage of successive phases, in particular syzygies (new moons and full moons), i.e. moments when the sun, earth and moon are in a straight line. So far, we have dealt only with the tidal action of the Moon. The Sun's gravitational field also acts on the tides, but although the Sun's mass is much larger than the Moon's, the distance from the Earth to the Sun is so much greater than the distance to the Moon that the Sun's tidal force is less than half that of the Moon. However, when the Sun and the Moon are on the same straight line, both on the same side of the Earth, and on different sides (on a new moon or a full moon), their attractive forces add up, acting along one axis, and the solar tide is superimposed on the lunar tide. Similarly, the attraction of the Sun increases the ebb caused by the influence of the Moon. As a result, the tides are higher and the tides are lower than if they were caused only by the pull of the moon. Such tides are called spring tides. When the gravitational force vectors of the Sun and Moon are mutually perpendicular (during quadratures, i.e. when the Moon is in the first or last quarter), their tidal forces counteract as the tide caused by the attraction of the Sun is superimposed on the ebb caused by the Moon. Under such conditions, the tides are not as high, and the tides are not as low, as if they were due only to the gravitational force of the Moon. Such intermediate tides are called quadrature. The range of high and low water levels in this case is reduced by approximately three times compared to the spring tide. In the Atlantic Ocean, both spring tides and quadrature tides are usually a day late compared to the corresponding phase of the moon. In the Pacific Ocean, such a delay is only 5 hours. In the ports of New York and San Francisco and in the Gulf of Mexico, spring tides are 40% higher than quadrature ones.
Lunar parallax inequality. The period of fluctuations in the heights of the tides, which occurs due to lunar parallax, is 271/2 days. The reason for this inequality is the change in the distance of the Moon from the Earth during the rotation of the latter. Due to the elliptical shape of the lunar orbit, the Moon's tidal force is 40% higher at perigee than at apogee. This calculation is valid for the port of New York, where the effect of the moon being at apogee or perigee is usually delayed by about 11/2 days from the corresponding phase of the moon. For the port of San Francisco, the difference in tide heights due to the moon being at perigee or apogee is only 32%, and they follow the corresponding phases of the moon with a delay of two days.
daily inequality. The period of this inequality is 24 hours 50 minutes. The reasons for its occurrence are the rotation of the Earth around its axis and the change in the declination of the Moon. When the Moon is near the celestial equator, the two high tides on a given day (as well as two low tides) differ little, and the heights of the morning and evening high and low waters are very close. However, as the Moon's north or south declination increases, morning and evening tides of the same type differ in height, and when the Moon reaches its greatest north or south declination, this difference is greatest. Tropical tides are also known, so called because the Moon is almost over the Northern or Southern tropics. The diurnal inequality does not significantly affect the heights of two successive low tides in the Atlantic Ocean, and even its effect on the heights of the tides is small compared to the overall amplitude of the oscillations. However, in the Pacific Ocean, the diurnal irregularity manifests itself in the levels of low tides three times more than in the levels of the tides.
Semi-annual inequality. Its cause is the revolution of the Earth around the Sun and the corresponding change in the declination of the Sun. Twice a year, for several days during the equinoxes, the Sun is near the celestial equator, i.e. its declination is close to 0°. The moon is also located near the celestial equator approximately during the day every fortnight. Thus, during the equinoxes, there are periods when the declinations of both the Sun and the Moon are approximately 0°. The total tide-forming effect of the attraction of these two bodies at such moments is most noticeable in areas located near the earth's equator. If at the same time the Moon is in the phase of a new moon or a full moon, so-called. equinoctial spring tides.
Solar parallax inequality. The period of manifestation of this inequality is one year. Its cause is a change in the distance from the Earth to the Sun in the process of the Earth's orbital motion. Once for each revolution around the Earth, the Moon is at the shortest distance from it at perigee. Once a year, around January 2, the Earth, moving in its orbit, also reaches the point of closest approach to the Sun (perihelion). When these two moments of closest approach coincide, causing the greatest net tidal force, higher tide levels and lower tidal levels can be expected. Similarly, if the passage of aphelion coincides with the apogee, less high tides and shallower low tides occur.
Methods of observation and forecast of tide heights. Tide levels are measured using various types of devices. A footstock is an ordinary rail with a scale in centimeters applied to it, attached vertically to a pier or to a support submerged in water so that the zero mark is below the most low level low tide. Level changes are read directly from this scale.
Float stem. These footstocks are used where constant swell or swell make it difficult to determine the level on a fixed scale. Inside a protective well (hollow chamber or pipe) vertically installed on the seabed, a float is placed, which is connected to a pointer fixed on a fixed scale, or a chart recorder pen. Water enters the well through a small hole located well below the minimum sea level. Its tidal changes are transmitted through the float to the measuring instruments.
Hydrostatic sea level recorder. At a certain depth, a block of rubber bags is placed. As the height of the tide (water layer) changes, the hydrostatic pressure changes, which is fixed measuring instruments. Automatic recording devices (tide gauges) can also be used to obtain a continuous record of tidal fluctuations at any point.
Tide tables. When compiling tide tables, two main methods are used: harmonic and non-harmonic. The non-harmonic method is entirely based on the results of observations. In addition, the characteristics of port water areas and some basic astronomical data (the hourly angle of the Moon, the time of its passage through the celestial meridian, phases, declinations and parallax) are involved. After correcting for these factors, the calculation of the moment of occurrence and the level of the tide for any port is a purely mathematical procedure. The harmonic method is partly analytical and partly based on observations of tide heights over at least one lunar month. To confirm this type of forecast for each port, long series of observations are needed, since due to such physical phenomena, as inertia and friction, as well as the complex configuration of the shores of the water area and the features of the bottom topography, distortions arise. Since tidal processes are inherently periodic, harmonic analysis is applied to them. The observed tide is considered as the result of the addition of a series of simple components of the tidal waves, each of which is caused by one of the tide-forming forces or one of the factors. For a complete solution, 37 such simple components are used, although in some cases the additional components beyond the 20 main ones are negligible. Simultaneous substitution of 37 constants into the equation and its actual solution is carried out on a computer.
Tides on rivers and currents. The interaction of tides and river currents is clearly visible where large rivers flow into the ocean. The height of the tides in bays, estuaries, and estuaries can increase significantly as a result of an increase in runoff in marginal streams, especially during floods. However, ocean tides penetrate far up the rivers in the form of tidal currents. For example, on the Hudson River, a tidal wave comes at a distance of 210 km from the mouth. Tidal currents usually spread upriver to difficult waterfalls or rapids. During high tides, the currents in rivers are faster than during low tides. Maximum speeds tidal currents reach 22 km / h.
Bor. When water, set in motion by a high tide, is limited in its movement by a narrow channel, a rather steep wave is formed, which moves upstream in a single front. This phenomenon is called a tidal wave, or bore. Such waves are observed on rivers much higher than the mouths, where the combination of friction and the flow of the river to the greatest extent hinders the spread of the tide. Boron formation is known in the Bay of Fundy, Canada. Near Moncton (Prov. New Brunswick), the Ptikodiak River flows into the Bay of Fundy, forming a marginal stream. In low water, its width is 150 m, and it crosses the drying strip. At high tide, a wall of water 750 m long and 60-90 cm high rushes up the river in a hissing and seething whirlwind. The largest known pine forest with a height of 4.5 m is formed on the Fuchunjiang River, which flows into the Hangzhou Bay. See also BOR. Reversing waterfall (reversing direction) is another phenomenon associated with tides on rivers. Typical example- a waterfall on the St. John River (Prov. New Brunswick, Canada). Here, along a narrow gorge, water at high tide penetrates into a basin located above the level low water, however, somewhat below the high water level in the same gorge. Thus, a barrier arises, flowing through which water forms a waterfall. At low tide, the flow of water rushes downstream through a narrowed passage and, overcoming an underwater ledge, forms an ordinary waterfall. At high tide, a steep wave that has penetrated the gorge falls like a waterfall into the overlying basin. The reverse current continues until the water levels on both sides of the threshold are equal and the tide begins to ebb. Then the waterfall is restored again, facing downstream. The average water level difference in the gorge is approx. 2.7 m, however, at the highest tides, the height of a direct waterfall can exceed 4.8 m, and a reverse one - 3.7 m.
The greatest amplitudes of the tides. The world's highest tide is formed by strong currents in Minas Bay in the Bay of Fundy. Tidal fluctuations here are characterized by a normal course with a semidiurnal period. The water level at high tide often rises by more than 12 m in six hours, and then drops by the same amount over the next six hours. When the action of the spring tide, the position of the Moon at perigee, and the maximum declination of the Moon occur in one day, the tide level can reach 15 m. the top of the bay.
wind and weather. Wind has a significant effect on tidal phenomena. The wind from the sea drives the water towards the shore, the height of the tide rises above normal, and at low tide the water level also exceeds the average. On the contrary, when the wind blows from the land, the water is driven away from the coast, and the sea level drops. Due to the increase in atmospheric pressure over a vast area of ​​water, the water level decreases, as the superimposed weight of the atmosphere is added. When atmospheric pressure increases by 25 mm Hg. Art., the water level drops by about 33 cm. A decrease in atmospheric pressure causes a corresponding increase in the water level. Therefore, a sharp drop in atmospheric pressure, combined with hurricane-force winds, can cause a noticeable rise in the water level. Such waves, although they are called tidal waves, are in fact not associated with the influence of tidal forces and do not have the periodicity characteristic of tidal phenomena. The formation of the mentioned waves can be associated either with hurricane force winds or with underwater earthquakes (in the latter case they are called seismic sea ​​waves or tsunami).
The use of tidal energy. Four methods have been developed to harness the energy of the tides, but the most practical of these is the creation of a system of tidal pools. At the same time, water level fluctuations associated with tidal phenomena are used in the lock system in such a way that the level difference is constantly maintained, which makes it possible to obtain energy. The power of tidal power plants directly depends on the area of ​​the trap pools and the potential level difference. The latter factor, in turn, is a function of the amplitude of the tidal fluctuations. The achievable level difference is by far the most important for power generation, although the cost of facilities depends on the size of the pools. At present, large tidal power plants operate in Russia on the Kola Peninsula and in Primorye, in France in the estuary of the Rance River, in China near Shanghai, and also in other regions of the globe.
LITERATURE
Shuleikin V.V. Physics of the sea. M., 1968 Harvey J. Atmosphere and Ocean. M., 1982 Drake C., Imbri J., Knaus J., Turekian K. The ocean itself and for us. M., 1982

Collier Encyclopedia. - Open Society. 2000 .

See what "ELBOW AND FLOW" is in other dictionaries:

- (Flood tide and ebb tide, ebb and flood) periodic changes in the water level in the sea caused by the action on water particles of the forces of attraction of the Moon and the Sun and the centrifugal forces arising from the circulation of the Earth-Moon, Earth-Sun systems around their common ... ... Marine Dictionary

ebbs and flows- - Telecommunication topics, basic concepts EN tides and currents ... Technical Translator's Handbook

The content of the article

Ebb and flow, periodic fluctuations in the water level (ups and downs) in the water areas on the Earth, which are due to the gravitational attraction of the Moon and the Sun, acting on the rotating Earth. All large water areas, including oceans, seas and lakes, are subject to tides to one degree or another, although they are small on lakes.

Reversible waterfall

(reversing direction) is another phenomenon associated with tides on rivers. A typical example is a waterfall on the St. John River (New Brunswick, Canada). Here, along a narrow gorge, water at high tide penetrates into a basin located above the low water level, but somewhat below the high water level in the same gorge. Thus, a barrier arises, flowing through which water forms a waterfall. At low tide, the flow of water rushes downstream through a narrowed passage and, overcoming an underwater ledge, forms an ordinary waterfall. At high tide, a steep wave that has penetrated the gorge falls like a waterfall into the overlying basin. The reverse current continues until the water levels on both sides of the threshold are equal and the tide begins to ebb. Then the waterfall is restored again, facing downstream. The average water level difference in the gorge is approx. 2.7 m, however, at the highest tides, the height of a direct waterfall can exceed 4.8 m, and a reverse one - 3.7 m.

The greatest amplitudes of the tides.

The world's highest tide is formed by strong currents in Minas Bay in the Bay of Fundy. Tidal fluctuations here are characterized by a normal course with a semidiurnal period. The water level at high tide often rises by more than 12 m in six hours, and then drops by the same amount over the next six hours. When the action of the spring tide, the position of the Moon at perigee, and the maximum declination of the Moon occur in one day, the tide level can reach 15 m. the top of the bay.

wind and weather.

Wind has a significant effect on tidal phenomena. The wind from the sea drives the water towards the shore, the height of the tide rises above normal, and at low tide the water level also exceeds the average. On the contrary, when the wind blows from the land, the water is driven away from the coast, and the sea level drops.

Due to the increase in atmospheric pressure over a vast area of ​​water, the water level decreases, as the superimposed weight of the atmosphere is added. When atmospheric pressure increases by 25 mm Hg. Art., the water level drops by about 33 cm. A decrease in atmospheric pressure causes a corresponding increase in the water level. Therefore, a sharp drop in atmospheric pressure, combined with hurricane-force winds, can cause a noticeable rise in the water level. Such waves, although they are called tidal waves, are in fact not associated with the influence of tidal forces and do not have the periodicity characteristic of tidal phenomena. The formation of these waves can be associated either with hurricane-force winds or with underwater earthquakes (in the latter case they are called seismic sea waves, or tsunamis).

The use of tidal energy.

Four methods have been developed to harness the energy of the tides, but the most practical of these is the creation of a system of tidal pools. At the same time, water level fluctuations associated with tidal phenomena are used in the lock system in such a way that the level difference is constantly maintained, which makes it possible to obtain energy. The power of tidal power plants directly depends on the area of ​​the trap pools and the potential level difference. The latter factor, in turn, is a function of the amplitude of the tidal fluctuations. The achievable level difference is by far the most important for power generation, although the cost of facilities depends on the size of the pools. At present, large tidal power plants operate in Russia on the Kola Peninsula and in Primorye, in France in the estuary of the Rance River, in China near Shanghai, and also in other regions of the globe.

Table: Information about tides in some ports of the world

TIDE INFORMATION FOR SOME PORTS IN THE WORLD
Port	Interval between tides		Average tide height, m	Spring tide height, m
	h	min
Cape Morris Jesep, Greenland, Denmark	10	49	0,12	0,18
Reykjavik, Iceland	4	50	2,77	3,66
R. Coxoak, Hudson Strait, Canada	8	56	7,65	10,19
St. John's, Newfoundland, Canada	7	12	0,76	1,04
Barntcoe, Bay of Fundy, Canada	0	09	12,02	13,51
Portland Maine, USA	11	10	2,71	3,11
Boston Massachusetts, USA	11	16	2,90	3,35
New York, pc. New York, USA	8	15	1,34	1,62
Baltimore, pc. Maryland, USA	6	29	0,33	0,40
Miami Beach Florida, USA	7	37	0,76	0,91
Galveston, pc. Texas, USA	5	07	0,30	0,43*
O. Maraca, Brazil	6	00	6,98	9,15
Rio de Janeiro, Brazil	2	23	0,76	1,07
Callao, Peru	5	36	0,55	0,73
Balboa, Panama	3	05	3,84	5,00
San Francisco, pc. California, USA	11	40	1,19	1,74*
Seattle, Washington, USA	4	29	2,32	3,45*
Nanaimo, British Columbia, Canada	5	00	...	3,42*
Sitka, Alaska, USA	0	07	2,35	3,02*
Sunrise, Cook Inlet, pc. Alaska, USA	6	15	9,24	10,16
Honolulu Hawaii, USA	3	41	0,37	0,58*
Papeete, oh Tahiti, French Polynesia	...	...	0,24	0,33
Darwin, Australia	5	00	4,39	6,19
Melbourne, Australia	2	10	0,52	0,58
Rangoon, Myanmar	4	26	3,90	4,97
Zanzibar, Tanzania	3	28	2,47	3,63
Cape Town, South Africa	2	55	0,98	1,31
Gibraltar, Vlad. Great Britain	1	27	0,70	0,94
Granville, France	5	45	8,69	12,26
Leith, UK	2	08	3,72	4,91
London, Great Britain	1	18	5,67	6,56
Dover, UK	11	06	4,42	5,67
Avonmouth, UK	6	39	9,48	12,32
Ramsey, oh Maine, UK	10	55	5,25	7,17
Oslo, Norway	5	26	0,30	0,33
Hamburg, Germany	4	40	2,23	2,38
* Daily tide amplitude.

Literature:

Shuleikin V.V. Physics of the sea. M., 1968
Harvey J. atmosphere and ocean. M., 1982
Drake C., Imbri J., Knaus J., Turekian K. The ocean itself and for us. M., 1982



Most of the volume of outer space is emptiness. But here and there, spherical clumps of matter - planets, moons, stars - rush past each other in a gigantic dance.

While doing their cosmic steps, they act on each other by the force of gravity, causing the oceanic waters to swell on the surfaces of the planets. Gravity is the gravitational force acting between all material objects without exception.

What are ebbs and flows?

Ocean tides are regular rises and falls in the water level of the World Ocean in response to gravitational influences, that is, to the forces of attraction. When the waters of the ocean rise to their highest point, which happens every 13 hours, it is called high tide. When the water drops to its lowest point, it is called low tide. If you come to relax on a sea beach at high tide, you observe the effect of worlds rushing past the Earth in the eternal darkness of space.

Related materials:

Why is the moon red?

What causes hot flashes?

The sun, moon and other bodies of the solar system affect the water and land of the Earth by the force of their gravity. But only the Moon and the Sun have practical influence. The sun, although it is very far away (149 million kilometers), is so massive that its gravitational force is strong.

The Moon is very small (its mass is 1/81 of the mass of the Earth), but it has a pronounced gravitational effect on the Earth due to its close distance from it (380,000 kilometers).

Interesting fact: when the sun, moon, and earth are in a line, that is, on a new moon, the tides are especially strong.

Despite the strong gravity of the huge Sun, the small Moon, due to its proximity to the Earth, has a much greater influence on the tides. In addition, the force of gravity of the moon varies markedly from area to area of ​​the earth's surface. These changes are due to different distances of different parts of the earth's surface from the moon at any given time.

Ebb and flow, as it is believed today, are caused by the attraction of the moon. So, the Earth turns to the satellite one way or another, the Moon attracts this water to itself - that's the tides. In the area where the water leaves - low tides. The earth rotates, ebbs and flows follow each other. Here is such a lunar theory, in which everything is fine except for a number of unexplained facts.

For example, did you know that the Mediterranean Sea is considered tidal, but near Venice and on the Evrikos Strait in eastern Greece, the tides are up to one meter or more. It is considered one of the mysteries of nature. However, Italian physicists have discovered in the east of the Mediterranean Sea, at a depth of more than three kilometers, a chain of underwater whirlpools, ten kilometers in diameter each. An interesting coincidence of anomalous tides and whirlpools, isn't it?

A regularity has been noticed, where there are whirlpools, in the oceans, seas and lakes, there are ebbs and flows, and where there are no whirlpools, there are no tides ... space, regardless of the rotation of the earth.

If you look at the earth from the side of the Sun, whirlpools, rotating together with the Earth, overturn twice a day, as a result of which the axis of the whirlpools precesses (1-2 degrees) and creates a tidal wave, which is the cause of the tides, and the vertical movement of ocean waters .

Top precession

Giant ocean whirlpool

The Mediterranean Sea is considered tidal, but near Venice and on the Evrykos Strait in eastern Greece, the tides are up to one meter or more. And this is considered one of the mysteries of nature, but at the same time, Italian physicists discovered in the east of the Mediterranean Sea, at a depth of more than three kilometers, a chain of underwater whirlpools, ten kilometers in diameter each. From this we can conclude that along the coast of Venice, at a depth of several kilometers, there is a chain of underwater whirlpools.

If in the Black Sea, the water rotated as in the White Sea, then the ebbs and flows would be more significant. If the bay is flooded by a tidal wave and the wave twists there, then the tides in this case are higher ... The place of whirlpools, and atmospheric cyclones and anticyclones in science, at the junction of oceanology, meteorology, and celestial mechanics studying gyroscopes. The behavior of atmospheric cyclones and anticyclones, I believe, is similar to the behavior of whirlpools in the oceans.

To test this idea, on the globe, where the whirlpool is located, I fixed the fan, instead of the blades, I inserted metal balls on springs. I turned on the fan (whirlpool) simultaneously rotating the globe both around the axis and around the Sun, and got an imitation of the ebb and flow.

The attractiveness of this hypothesis is that it is quite convincingly tested by a whirlpool fan attached to the globe. The sensitivity of the whirlpool gyroscope is so high that the globe has to be rotated extremely slowly (one revolution in 5 minutes). And if a whirlpool gyroscope is installed on a globe, at the mouth of the Amazon River, then without a doubt, it will show the exact mechanics of the ebb and flow of the Amazon River. When only the globe rotates around its axis, the gyroscope-whirlpool tilts in one direction and stands still, and if the globe is moved in orbit, the whirlpool-horoscope begins to oscillate (precess) and gives two high and low tides per day.

Doubts about the presence of precession in whirlpools, as a result of slow rotation, are removed by the high speed of overturning whirlpools, in 12 hours .. And do not forget that the orbital speed of the earth is thirty times greater than the orbital speed of the moon.

The experience with the globe is more convincing than the theoretical description of the hypothesis. The drift of whirlpools is also associated with the effect of the gyroscope-whirlpool, and depending on which hemisphere the whirlpool is located in, and in which direction the whirlpool rotates around its axis, the direction of whirlpool drift depends.

floppy disk

Tipping gyroscope

Experience with a gyroscope

Oceanologists in the middle of the ocean are not actually measuring the height of the tidal wave, but the wave created by the gyroscopic effect of the whirlpool created by precession, the whirlpool's axis of rotation. And only whirlpools can explain the presence of a tidal hump on the opposite side of the earth. There is no fuss in nature, and if whirlpools exist, then they have a purpose in nature, and this purpose, I believe, is the vertical and horizontal mixing of ocean waters, to equalize the temperature and oxygen content in the world's oceans.

And lunar tides, if they existed, would not mix the ocean waters. Whirlpools, to some extent, keep the oceans from silting up. If a couple of billion years ago, the earth really rotated faster, then the whirlpools were more active. The Mariana Trench and the Mariana Islands, I believe the result of the whirlpool.

The tide calendar existed long before the discovery of the tidal wave. As existed, and the usual calendar, before Ptolemy, and after Ptolemy, and before Copernicus, and after Copernicus. Today there are incomprehensible questions about the characteristics of the tides. So, in some places (the South China Sea, the Persian Gulf, the Gulf of Mexico and the Gulf of Thailand) there is only one high tide per day. In a number of regions of the Earth (for example, in the Indian Ocean), there is either one or two high tides a day.

500 years ago, when the idea of ​​ebbs and flows was being formed, thinkers did not have enough technical means to test this idea, and little was known about the whirlpools in the oceans. And today, this idea, with its attractiveness and plausibility, is so ingrained in the minds of the public and thinkers that it will not be easy to abandon it.

Why, every year and every decade, on the same calendar day (for example, the first of May) in the mouths of rivers and bays, there is no identical tidal wave? I believe the whirlpools that are in the mouths of rivers and bays drift and change their size.

And if the cause of the tidal wave was the gravity of the moon, the height of the tides would not change for thousands of years. There is an opinion that a tidal wave moving from east to west is created by the attraction of the moon, and the wave floods the bays and estuaries. But why, the mouth of the Amazon floods well, and the Gulf of La Plata, which is located south of the Amazon, does not flood very well, although the Gulf of La Plata in all respects should flood more than the Amazon.

I suppose a tidal wave at the mouth of the Amazon is created by one whirlpool, and for the neck of La Plata a tidal wave is created by another whirlpool, less powerful (diameter, height, revolutions).

Maelstrom of the Amazon

A tidal wave crashes into the Amazon at a speed of about 20 kilometers per hour, the wave height is about five meters, the wave width is ten kilometers. These settings are more suitable for the tidal wave created by the precession of a whirlpool. And if it were a lunar tidal wave, then it would crash at a speed of several hundred kilometers per hour, and the width of the wave would be about a thousand kilometers.

It is believed that if the depth of the ocean was 20 kilometers, then the lunar wave would move as it should be 1600 km / h, they say that the shallow ocean interferes with it. And now it crashes into the Amazon at a speed of 20 km/h, and into the Fuchunjiang River at a speed of 40 km/h. I guess the math is questionable.

And if the Moon wave moves so slowly, then why in the pictures and animations the tidal hump is always directed towards the Moon, the Moon rotates much faster. And it is not clear why, the water pressure does not change, under the tidal hump, at the bottom of the ocean ... There are zones in the oceans where there are no ebbs and flows at all (amphidromic points).

amphidromic point

M2 tide, tide height shown in color. White lines are cotidal lines with a phase interval of 30°. Amphidromic points are dark blue areas where white lines converge. Arrows around these points show the direction of "running around".An amphidromic point is a point in the ocean where the amplitude of the tidal wave is zero. The height of the tide increases with distance from the amphidromic point. Sometimes these points are called tidal nodes: the tidal wave "runs" around this point clockwise or counterclockwise. The cotidal lines converge at these points. Amphidromic points arise due to the interference of the primary tidal wave and its reflections from the coastline and underwater obstacles. The Coriolis force also contributes.

Although for a tidal wave, they are in a convenient zone, I believe in these zones the whirlpools rotate extremely slowly. It is believed that the maximum tides occur in the new moon, for the reason that the Moon and the Sun exert gravity on the Earth in the same direction.

For reference: a gyroscope is a device that, due to rotation, reacts differently to external forces than a stationary object. The simplest gyroscope is the top. By spinning the top on a horizontal surface and tilting the surface, you will notice that the top retains horizontal torsion.

But on the other hand, in the new moon, the orbital speed of the earth is maximum, and in the full moon, it is minimum, and the question arises which of the reasons is the key. The distance from the earth to the moon is 30 diameters of the earth, the approach and removal of the moon from the earth is 10 percent, this can be compared by taking a cobblestone and a pebble with outstretched arms, and bringing them closer and further away by 10 percent, are tides possible with such mathematics. It is believed that in the new moon, the continents run into a tidal hump, at a speed of about 1600 kilometers an hour, is this possible.

There is an opinion that tidal forces have stopped the rotation of the moon, and now it rotates synchronously. But there are more than three hundred known satellites, and why they all stopped at the same time, and where did the force that rotated the satellites go ... The gravitational force between the Sun and the Earth does not depend on the orbital speed of the Earth, and the centrifugal force depends on the orbital speed of the Earth, and this fact cannot be the cause of the Lunar ebb and flow.

Calling the tides, the phenomenon of horizontal and vertical movement of ocean waters, is not entirely true, for the reason that most whirlpools do not contact the ocean coastline ... If you look at the Earth from the side of the Sun, whirlpools that are located in the midnight and noon side of the earth more active, as they are in the zone of relative motion.

And when the whirlpool enters the zone of sunset and dawn and becomes an edge to the Sun, then the whirlpool falls into the power of the Coriolis forces and subsides. In the new moon, the tides increase and ebb for the reason that the orbital speed of the earth is maximum ...

Material sent by the author: Yusup Khizirov

In order to exhaust the main questions connected with the existence of its satellite near the Earth - the Moon, we need to say a few words about the phenomenon of tides. It is also necessary to answer the 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 tide (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. Not long ago, steamboats sailed in these places, and now the inhabitants 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. In the side facing the Moon at the moment, 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 turns in different directions to all heavenly bodies, including the Moon (daily 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. Therefore 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 of universal gravitation. 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 the surface of the Earth are attracted by the Moon to a lesser extent than the interior 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 the solid inner parts of the globe, and here, too, there is a rise of water, a water hump, a tidal height, approximately the same as on the 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, there must be two high tides and two low tides on the Earth during the period of a complete rotation of the Earth around its 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 the Moon is at a given time. 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 so small, is, as we know, very noticeable for the inhabitants of the Earth located near the coast of the oceans.