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Tides and Ocean Currents


In this lesson you can learn a lot of facts about tides and ocean currents.

 

tides and ocean currents

 

Tides and Ocean Currents Facts

 

Tides

 

What are tides?

 
The rise and fall of the level of the oceans and seas twice a day are tides. Tides can move the seawater from place to place.

 

What causes tides?

 
The gravitational attraction of the moon and the sun upon the water and upon the earth itself causes tides.

 

What are the two main types of tides?

 
1) Ordinary tide
2) Spring tide

 

What are the two main types of ordinary tides?

 
a) High tide
b) Low tide
 

high tides low tides

 

Ordinary Tide

 

High tide and low tide are ordinary tides.

 

High Tide

 

What is high tide?

 
Twice each day, the level of the ocean or sea rises and water covers the shore. Then we say that the tide is ‘in’. This is called ‘high tide’.

 

What is the advantage of high tide?

 
High tide brings deep water to harbours and ports so that the ships can sail in and out.

 

What is the disadvantage of high tide?

 
High tide may cause flooding.

 

Low Tide
 

What is low tide?

 
Twice each day, the level of seawater falls. The seashore is uncovered. Then we say the tide has ‘gone out’. This is called ‘low tide’.

 

How are ordinary tides (High tide and Low tide) occurred?

 
Ordinary tides are caused by the combined pull of gravity of the Sun, and of the Moon as it circles the Earth.

 

Spring Tide

 

How often spring tides occur?

 
These tides occur twice a month.

 

How are spring tides occurred?

 
When the Sun and Moon are both on the same side of the Earth these tides are occurred. The pull of both the Sun and Moon makes the water pile up higher than usual.

 

Waves

 

What are waves?

 
Waves are big ripples of water caused by the wind. Waves make the water move up, down and around. Waves do not move the seawater from place to place. Huge waves can batter down rocks, wear away cliffs and lift big pieces of rock.
 

 

Ocean Currents

 

What are ocean currents?

 
This is a powerful movement of water that has a steady flow in one direction. Ocean currents can move the seawater from place to place.

 

What are the two main types of ocean currents?

 
1) Warm Currents
2) Cold Currents

 

Warm Currents

 

What are warm currents?

 
Currents coming from colder regions in the ocean to warmer regions in the ocean are called warm currents.

 

Examples of warm currents
 

  • The Gulf Stream
  • Caribbean current
  • North Equatorial current
  • Equatorial Counter current
  • Brazil current
  • North Atlantic Drift
  • East Australian current
  • South Equatorial current
  • North Pacific current
  • Agulhas current 

 

Cold Currents

 

What are cold currents?

 
Currents coming from warmer regions in the ocean to colder regions in the ocean are called cold currents.

 

Examples of cold currents
 

  • West Wind Drift
  • California current
  • Peru current
  • Falkland current
  • Bengue current
  • Canaries current
  • Greenland current
  • West Australian current
  • Kuril current
  • Labrador current

 

What is the importance of ocean currents?

 

Ocean currents help to distribute heat around the Earth and have a great influence on climate.
 
We hope you learned important facts about tides and ocean currents.
 
Also, read the lessons Coasts and coastal Landforms.