Oceanic Movement waves, tides and currents

How the Oceanic Movement Occurs?

The Ocean Water Never remains Static, it is always dynamic and keeps on moving... Oceanic movement can be caused by various forces, including Gravity of the Moon and Sun, Blowing Wind, Rotation of The Earth (Carolus Force), Concentration of (minerals) Salts and temperature of the water, etc.

The movement of the ocean can be divided into three types 

• Waves 
• Tides 
• Currents

Waves 

A Wave is an Oscillary (swinging) movement in the Sea-water, It is manifested (Demonstrated) by an alternate rise and fall of the water surface

A wave is divided into two main parts, the top part which is its Crest and the lower part is known as its Trough.

Every wave has its own Wavelength, Wave Period, Wave Velocity which are described here briefly.

Wave Length:

The Distance in which a wave completes its Cycle is termed as Wavelength...It is the distance between either adjacent crest (Upper-end) or trough (Lover-end) of a wave is known as wavelength, it is influenced by the depth of water, Velocity of wind, duration of the wind, and bottom topography.

The formation full and unrestricted wave occurs where the deep water, Strong and continuously moving winds, and not interfering bottom is present.

Wave Height

It is the vertical distance between Crest and Trough of a wave, the hight of a wave is directly related to wind velocity and duration (Period).
the wind having high and constant velocity results in a higher wave, which is most common in the Moths of June and July in the Nothern Hemisphere, and December, January in Southern Hemisphere.

Wave Period (P)
The wave period is the time that takes a wave to complete its Cycle.

Wave Frequency:
the Wave frequency is the Number of Cycles produced in a Second.

Formation of a Wave 

When blows over the surface of the ocean water, it causes a movement called the wave. in this kind of movement, the water does not change its position (Horizontal). eg one can easily understand the Process having a simple experiment: just Putting a Piece of Cork in a Pond, it would be noticed that waves are moving but pice of Cork does not change its Position; it means that during wave water does not changes its position, the only vertical movement takes place in the water.

The Blowing-wind having low velocity Produces lower-grade waves, however, higher wind velocity results in High and Strong waves. 

Tides

It is the Movement of the Ocean water caused by the Gravitational force of the Earth, the Moon and the Sun called tides, because of that Seawater Regularly Rise and Fall twice a day. the seawater rises up and it runs towards the Coasts or enters a Gulf. 

The Tides which move towards the Coast or enters a gulf called Flood or incoming tide, and when the water moves away from the Gulf or Coast is known as Ebb or Out Going tide.


 At the seaside, it is noticed that the level of sand or rock at the foot of the Cliffs is now covered by the sea and now left bare.

Every month there is a great tide which occurs on the night of Full Moon, it is mainly due to the attraction exerted by the Moon on the water of the ocean that tides are caused. As the attraction of the Moon on water (A Fluid) is greater than its attraction on the earth  (a Solid) water is heaped up at the point directly under the Moon, The water level on the other side of the globe falls down at the same time.

The Sun has also an attraction on both Water and Land, But being away it has no appreciable effect it is the tides that reduce great rocks to fragments and keep the ocean water moving. They are also of enormous economic importance to the main kind.

Water can be stored in upraised tanks and allowed to run down in hydro-electric plants and turn the wheels of huge generators.   

People living on the coastline are well known for tides.

The tides can also be defined as the up and down movement of water due to the Gravitational Force  (Attraction) of the Sun and Moon.

How gravitational force forms the tides?

The distance between Moon and Earth is 0.385 Million Kilometers, However, the distance between the Sun and the Earth is 149.6 million kilometers.

As compared to the Sun, the Moon is closer towards Earth, therefore, the Gravity of the Moon towards Earth is greater than the Sun.

Due to closeness towards the Earth, The Moon takes a chance to Show its force hence due to that force relatively higher tides are formed.

 

Classification

The tides are classified into two types.

01. Neap Tides

02. Spring Tides

Neap Tides:- This kind of tides is formed due to the Gravity of  Either The Sun or The Moon.

Spring Tides:- This tide is formed due to the attraction of sun and Moon at once

Oceanic Currents:

Current means flow, like Electric Current (Flow of Charge). similarly, an Oceanic Current is the flow of Ocean water in a particular direction like a river called oceanic current, therefore an Oceanic current can be defined as, the flow of water in the ocean like a river called oceanic current.

The Oceanic Currents are called the Rivers of warm and cold water flowing in an ocean. Just as a Motion of the air is due to the difference in atmospheric pressure at different places. similarly, the Movement of oceanic water is the difference in temperature of the water. when anybody of water heated in one place and cooled in another and the differences of density are produced, which set up convection currents, as for example: if you heat water in a pot from below; the water will begin to move in upward and downward currents.

In the ocean, there are slow general circulations due to the settling of cold, dense water to the bottom in the polar seas.

The cold water flowing bottom moves from north to the South, along the bottom in the polar areas cold water flows getting warm at the surface and flowing again towards the poles thus even the deepest part of the ocean is the animal life that is found even at the greatest depth. 

Deep-sea organisms depend on their life on oxygen dissolved in the water. In case the water was not circulation this would soon be exhausted.

Currents also owe their origin directly or indirectly to the prevailing winds. 

If winds blow in the direction for a considerable period of time they cause part of ocean water to flow in the same direction and thus produce currents.

Formation of Oceanic Currents:

The oceanic currents are formed, due to various factors some of them are discussed here.

1. Difference in Temperature

 The regions which are present at the Equator receive direct Sunlight, because of that the water remains warm, its density is reduced and its surface is raised; In other hands, the Polar areas or areas (high latitude) which receives less sunlight, has high water density, the water surface does not rise, in this way water moves to those areas (from Low latitudes to high latitudes).

Warm water remains less dancer because of that the surface of water remains high, however  as mentioned above the Oceanic regions which are present at the Polar areas  do not receive direct sunlight.because of that density of water in that region is higher than the Polar areas, because of that a slope is developed between both areas,  in this way currents move from equator to polar areas 

Difference in Salinity

In the area between both the Tropics (Torrid Zone), receives vertical sunlight, therefore there is a high evaporation rate. because of high evaporation, the amount of salinity is increased in that region because salinity water becomes heavy as comported to polar areas, therefore, this heavy water moves towards the polar areas.

Trade Winds

Trade winds also cause the formation of oceanic currents these winds decide the Direction of oceanic water, as the wind changes its direction with that the Ocean water is also taken its way to that side. E.g. Currents of Indian and Atlantic Ocean

Earth Rotation

Earth rotation does not cause the formation of oceanic currents, but it changes the direction of currents.

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