KERALA PSC / PHYSICAL GEOGRAPHY / OCEAN MOVEMENTS / NOTES / OBJECTIVE QUESTIONS / STUDY MATERIALS / GENERAL KNOWLEDGE

 

KERALA PSC / PHYSICAL GEOGRAPHY / OCEAN MOVEMENTS / NOTES / OBJECTIVE QUESTIONS / STUDY MATERIALS / GENERAL KNOWLEDGE

KERALA PSC / PHYSICAL GEOGRAPHY / OCEAN MOVEMENTS / NOTES / OBJECTIVE QUESTIONS / STUDY MATERIALS / GENERAL KNOWLEDGE

·      There are three types of motions in the oceans viz, the tides, the waves and the currents

 

Ocean Currents

·      General movement of a mass of surface water in a fairly defined direction is known as an ocean current

·      Ocean currents are of two kinds

Ø Warm currents which flows from a warmer region to a colder region (equatorial to the polar regions)

Ø Cold currents which flow from a colder to a warmer region (polar region to the equatorial region)

·      Ocean currents are caused by several interacting forces. One of the prime causes, particularly of surface currents is wind

·      Differences in water density can also set currents in motion and these are described as thermodine currents

·      Besides the horizontal movement, vertical circulation by ocean water is also an important phenomenon for ocean currents

·      Florida current and Brazil current are warm currents of the Atlantic Ocean

·      Kuroshio current is in the Pacific Ocean

·      The North equatorial Current that flows along Taiwan and Japan are called Kuroshio current

·      Gulf Stream is in the Atlantic Ocean

·      Agulhas current is a major warm current of Indian Ocean

·      Ocean currents change their direction annually in the Indian Ocean

·      Labrodor, Canaries, Beneguela and Falkland are cold currents of Atlantic Ocean

·      Alaska, Peruvian or Humboldt and California are cold currents of the Pacific Ocean

·      Ocean currents influence the climate of the regions they pass through

 

Tides

·      Tide is the periodic rise and fall of sea water. The tides are caused by gravitational pull of the moon and sun on earth’s sea water

·      The time period between a high tide and a low tide is approximately six hours. Each of them happens twice a day

·      Highest tidal amplitude and range was found in Bay of Fundy

·      Highest tides recorded in India is at Okha, Gujarat

·      Generally, tides occur twice a day. But in Southampton, along the southern coast of England, experiences tides 4 times a day

·      A rise in the water level is called high tide and a fall is called low or ebb tide. Tides are of two types, Spring Tides and Neap Tides

·      Spring Tides are caused as a result of the moon and sun pulling the earth gravitationally in the same direction. They occur twice a month around the full moon and new moon. It is the tide of maximum rise.

·      Neap Tides are caused when the moon and the sun pull the earth gravitationally in opposite directions. These tides are produced when the moon and the sun are at right angles to the earth. It is the tide of minimum rise, occurring twice a month. They occur on half - moon days.

KERALA PSC / PHYSICAL GEOGRAPHY / OCEAN MOVEMENTS / NOTES / OBJECTIVE QUESTIONS / STUDY MATERIALS / GENERAL KNOWLEDGE