Understanding the tides and ebbs of sea water – When Grameds goes to the beach, Grameds will certainly encounter sea water that rises and falls. The event of rising and falling sea water is one of the appearances of the Earth which is influenced by the gravitational force of the Sun and Moon.

The tides and ebbs of sea water is an event of changes in the height or low of the sea level due to the gravitational force of astronomical bodies, especially the Sun and Moon. High tide is a rise in sea level, while low tide is a decrease in sea level. Because the Earth rotates, in one day, a place will experience two highs and lows of sea water.

In order to better understand the meaning of tides and ebb and related theories, here is a further explanation of the tides and ebb of sea water.

Understanding the Tides and Ebb of Seawater

This natural event that describes the tides is very useful, especially when it is used by people with the fishing profession to become a benchmark in sailing and fishing.

When the sea water is at low tide, then this time is the right time to go sailing. And vice versa, if the sea is in high tide, then this time is the right time for fishermen to return home.

Sea tide is a condition where the water in the sea structure rises. While receding is a condition where sea water is falling. Literally, the two definitions of high tide and low tide can be concluded that high tide is a condition when sea water is experiencing a rise and fall in its surface.

According to the Ministry of Marine Affairs and Fisheries (2018), tides are a depiction of fluctuations in sea level as a function of time caused by the gravitational pull of objects in the sky, especially influenced by the presence of the Sun and Moon on the mass of sea water on Earth. .

The Theory of Tides and Ebbs and Flows of the Sea

The ebb and flow of sea water is a natural phenomenon in the form of periodic movement of sea water, where the phenomenon of sea tides is caused by the presence of gravitational forces and the pulling and dancing forces of objects in the sky, especially the sun and moon.

High tide occurs when the water rises and moves until it reaches the farthest limit from the shoreline. In general, high tide will occur at noon. Therefore, in the middle it is not recommended to play sea water first.

Conversely, low tide occurs when the water drops and then moves away from the shoreline. The rising and falling of sea water without mass transfer is called a wave.

As previously explained, the phenomenon of tides is the result of gravitational attraction and centrifugal effects originating from the outward thrust of the center of rotation. Gravity varies directly with mass but inversely with distance.

The gravitational force that is presented is greater than that of the Sun. Even though in terms of size, the Moon is much smaller than the Sun, the Moon has a much greater gravitational force, even up to two times that of the Sun, in causing other water ebb and flow phenomena. This is because the Moon is closer to Earth than the Sun.

This gravitational force pulls seawater towards the Moon and also the Sun, thus producing two bulges or bulges of gravitational tides in the sea. There are several theories that examine the ebb and flow of sea water, including the Theory of Balance or Equilibrium Theory and Dynamical Theory.

To be more clear, here is an explanation of the two theories of tides and tides.

1. Theory of Balance (Equilibrium Theory)

The theory of tides and ebbs of sea water this one put forward by Sir Isaac Newton. Theory of Balance or Equilibrium Theory explains the nature of the tides and ebbs of seawater qualitatively.

This theory occurs on an ideal Earth where the entire surface of the earth is covered by water and the influence of moisture is ignored. The theory of balance also states that the rise and fall of sea level is proportional to the presence of tidal and ebb generating forces.

So, to understand the generating force of the tides and ebbs, it is done by separating the movements of the Earth, Moon and Sun systems into two types, namely Earth Moon and Earth Sun.

The theory of balance assumes that the Earth is covered by water, where the depth and density are the same and the rise and fall of the sea level is proportional to the tidal generating force or the resultant gravitational force of the Moon and centrifugal force.

The theory of balance has to do with the relationship between the sea, rising water masses, the Moon and the sun, where the generating force will cause the water to be high in two locations and the water to be low in two locations.

2. Dynamic Tidal Theory (Dynamical Theory)

The dynamic tide theory was put forward by Laplace. This Dynamical Theory theory complements the balance theory put forward by Isaac Newton, so that the nature of the tides and ebbs of sea water can be known quantitatively.

The dynamic tidal theory states that homogeneous oceans are still assumed to cover the entire surface of the Earth with a fairly constant depth.

However, the existence of periodic attraction forces can generate waves with periods that match their constituents. This dynamic theory also states that tidal waves are formed due to the influence of the resultant gravitational force of the Moon and centrifugal force, the depth and breadth of the waters, the influence of the Earth’s rotation and the influence of bottom friction. Apart from these factors, according to the dynamic theory of tides, sea water is also influenced by the following three other factors:

• Water depth and water area
• The influence of the Earth’s rotation
• The basic friction of the Earth’s rotation

Those are the two theories that study the ebb and flow of sea water and that is also the concept of sea water which in essence occurs ups and downs of sea water due to gravity and the attractive force of objects in the sky, especially the Sun and Moon.

The Causes and Processes of the Occurrence of the Tides and Ebb of Seawater

In the concepts and theories about the tides and ebbs of the sea that have been put forward previously, Grameds now knows that the occurrence of the tides and lows of the seas is due to the influence of the gravitational force and the attractive force of objects in the sky.

However, to find out more about the causes, it would be nice if Grameds went deeper because in reality, there are several factors that contribute to the occurrence of tides and ebbs in sea water. Several factors that cause the occurrence of tides and ebbs are divided into two based on the theory of balance and dynamic theory.

Causes of Tides and Ebbs of Sea Water

1. According to the Theory of Balance

According to the balance theory initiated by Isaac Newton, the ebb and flow of sea water is influenced by the following factors:

a. Earth’s rotation on its axis

Earth’s rotation is one of the factors that influence the occurrence of tides and ebbs in sea water. Earth’s rotation is an event in which the Earth rotates on its axis or on its axis.

When the Earth rotates, there are times when the position of a sea area is facing the Moon and there are times when the position is facing the Sun.

Seawater will meet the Moon at night. Because previously it was said that the gravitational force of the moon is greater than that of the sun, it is not surprising that sea water experiences high tide at night.

b. Earth’s revolution around the Sun

According to the balance theory, the Earth’s revolution on the Moon is one of the factors that influence the ebb and flow of sea water. Revolution is an event in which the celestial bodies rotate around other celestial bodies which are the center.

One of the objects that make revolutions is the planet, and Earth is no exception. planets make revolutions around the Sun which is the center of the solar system.

With this revolution, now we can have years. The Earth’s revolution around the sun is one of the factors that causes the ebb and flow of sea water because there are times when the Earth approaches the Sun and there are times when the Earth moves away from the Sun. This is partly due to the oval-shaped trajectory or orbit of the Earth.

c. Revolution of the Moon on the Sun

If the previous factor causing the tides and ebbs of the sea was the revolution of the Earth on the Sun, then the next factor was the revolution of the Moon on the Sun.

As it is known that the Moon is a natural satellite of the Earth, but in fact the Moon has a double revolution, namely with the Earth and also the Sun.

When the Moon undergoes a revolution together with the Earth, then there is one possibility that the Sun and the Moon are at a point that is quite close.

That way, the strength of the attraction of the two will combine and then be able to pull the sea surface stronger than in normal conditions.

2. According to the Dynamic Theory

In addition to the causes of tides and ebbs, Grameds also needs to know how the processes of tides and ebbs occur? To make it clearer, here is the explanation. The cause of the tides and ebbs of sea water, is also explained according to the dynamic theory. According to this theory, there are three factors that cause the ebb and flow of sea water.

a. Depth and area of ​​water

The depth and breadth of the waters of a sea are different. Not only that, sometimes these seas have different seabed topography.

The depth and breadth of these waters seems to have had an impact on the tides and ebbs of sea water, where seas with deeper depths will be different from seas which tend to have shallower depths. Likewise with the area of ​​sea waters, tides and ebb will be different in seas with a wide area and seas that tend to be narrower.

b. Effect of Earth’s rotation

As explained in the theory of balance, the Earth’s rotation is one of the factors that cause the tides and ebb of sea water. Earth’s rotation is an event when the earth rotates on its axis.

When the Earth rotates, then the time from the position of a sea area facing towards the Moon and there are also areas facing towards the Sun.

The sea water will then meet the Moon at night, so that the sea water also experiences tides at night.

c. Basic friction

According to the dynamic theory, the tides and ebb of sea water are influenced by the presence of friction on the seabed. This friction occurs on the plates in the ocean.

When the Earth’s plates rub against one another, sometimes these plates will create a kind of cavity that will absorb seawater.

When sea water is absorbed, even on the surface the water will appear to recede. Conversely, if the water comes back out, then the sea level will appear high.

3. Topography of the seabed

Another factor beyond the sweetened theory and equilibrium theory is the topography of the ocean floor. Seabed topography is the state of the landscape on the seabed or ocean floor.

The condition of the landscape seems to be one of the factors that influence the ebb and flow of sea water. The topography is flat, the intensity and magnitude of the tides and ebbs will not be the same as the sea which has a diverse topography.

4. The width of the strait

The strait is the water that separates the two islands. In general, the strait is narrower than the sea because it is flanked by two islands. The width of the strait is one of the factors that causes the ebb and flow of sea water.

5. The shape of the bay

Apart from the width of the strait and the topography of the seabed, other factors that cause tides and ebbs are the shape of the bay. The bay is the part of the land where the sea water protrudes more into the land.

The bay can be likened to a cake that has been bitten and causes there are some parts that are more inland. The shape of the bay is also a factor that influences the tides and ebbs.

A bay which is a sloping beach will have different ups and downs from a bay which is a steep cliff. Especially when the tide occurs. A more sloping beach will look high when compared to the steep cliff wall, because it is held by the cliff wall.

The Occurrence of The Occurrence of Sea Water Ebb and Tide

After knowing the several factors that cause the tides and ebbs of sea water, how does the process of the tides occur? As has been explained that the main factors of tides are the Earth’s gravitational force on the Moon and the Earth’s rotation.

When the side of the Earth is closest to the Moon, that side will experience the Moon’s gravitational pull which is strong enough, so that sea water rises or tides occur. This is the process of the tide.

Meanwhile, on the side of the Earth that is far from the Moon, the Earth’s rotational force will be stronger than the Moon’s gravitational pull. The Earth’s rotational force causes water to accumulate when trying to hold it back. When water accumulates, there is a high tide.

Low tide will occur when the other hemisphere feels the moon’s small gravitational force. Low tide will also occur in other areas that do not experience high tide, because other parts of the sea will take rations from other hemisphere and cause low tide.

That is the explanation of the meaning of the tides and ebb of sea water. If Grameds wants to learn more about geography, then Grameds can read books. Hopefully all the discussion above can be useful as well as add to your insight.

As #Friends Without Limits , gramedia.com provides a variety of original and useful books for Grameds.

Author: Khansa

Also read regarding the definition of tides and ebbs of seawater and its theories:

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