MAJOR OCEANS AND SEAS
WHY IS WATER IMPORTANT?
- Water is an important constituent of all life forms.
- Hydrosphere is one among four spheres lithosphere, atmosphere and biosphere.
- The hydrosphere includes oceans, rivers, lakes and glaciers, groundwater and water on earth’s surface.
WHAT IS AN OCEAN?
- The term ocean derived from the Greek word “Oceanus” means enormous river encircling the earth.
- Five major oceans in the world -Pacific Ocean, Atlantic Ocean, Indian Ocean, Arctic Ocean and Southern Ocean.
Pacific Ocean
- It is the world’s largest ocean.
- It is bigger than all the continents put together.
- It covers one-third of the earth’s surface area.
- The Pacific Ocean separates American continents from Asia and Australia.
- The International Date Line passes through the Pacific Ocean.
- The Pacific Ocean joins the Indian Ocean through the Indonesian Seaway.
- The average depth of this ocean is about 4280 m.
- The deepest Mariana trench located in the western Pacific Ocean.
Atlantic Ocean
- It is the second largest ocean after Pacific.
- It covers about 20% of the earth’s surface.
- Its name is derived from the Greek mythology- Atlantis Thalassa.
- It is an elongated S- shaped water body between Africa, Europe and other continents
- Average depth of this ocean is about 3,646 m.
- Deepest trench in the Atlantic Ocean is Puerto Rico Trench.
Indian Ocean
- It is the only ocean in the world named after a country.
- It is named after India which makes up much of its northern border.
- It lies in the eastern hemisphere.
- It covers about 19.8 % of water on the earth’s surface.
- It lies between Africa, Southern Ocean, Australia and Asia.
- It is landlocked a closed and warmest ocean.
- The largest island in the Indian ocean is Madagascar.
- Sunda trench/ is the deepest trench in the Indian ocean.
Southern Ocean
- Also known as the Antarctic Ocean.
- It comprises the southernmost waters of the world ocean.
- It is the fourth largest ocean in the world.
- It shares its northern boundary with the Atlantic, Indian and Pacific Ocean.
- It is known for its violent storms.
Arctic Ocean
- The Arctic Ocean is shallower and smaller ocean.
- It lies entirely within the Arctic Circle.
- It covers about 1.3% of the earth’s water surface area.
- It is surrounded by Eurasia and North America.
- It is completely covered by ice in winter.
- The Molloy Deep is the deepest point in the Arctic Ocean.