ICSE Class 9 Answered

Oceans are extremely important to human life. The following are the importance of oceans:

• Fish is an important source of food and nutrition to human life. Fishes have been consumed by man since prehistoric times.

   

• Fishing has become a well developed industry today and significantly contributes to the economy of many nations.

   

• Oceans provide food and other marine products to humans. Several kinds of edible oil are manufactured by humans from marine animals.

   

• Besides food and oil, marine animals and plants provide leather, glue, cattle feed etc.

   

• Much research is being done to extract essential oil and products of marine life that can cure different diseases. Marine pharmacologists are researching on the physical and chemical properties of marine organisms like crabs, sea cucumbers, sharks, cods etc.

   

• Oceans provide us with a variety of mineral resources. Some of these are common salt, magnesium and bromide.

   

• The most important minerals obtained from the sea are petroleum and natural gas. Petroleum known as ‘Black Gold’ is mainly found in the continental shelves and slopes. Bombay High in India is an important source of oil in India.

   

• Oceans also provide us with non conventional sources of energy like tidal energy and the energy generated through waves. The rise and fall of sea water is known as the tides. Powerful tidal waves generate huge amounts of force when they strike the shore. This energy is used by generators to produce electricity.

   

• Many countries are researching the prospects of harassing energy from the surface of the ocean waters. The water at the surface of the sea in the tropical regions may reach upto 30⁰C. Belgium and Cuba have designed floating generators that can be used for the production of electricity.

   

• Oceans have been used as a means of transport since ancient times. Water transport is one of the cheapest means of transport in the world.

   

• Oceans also regulate the temperature of the Earth. They cover about 71% of the Earth’s surface. They store the heat of the Sun and keep the Earth warm. This is because they absorb the heat of the Sun and release it after a long time. On the other hand, land gets heated and releases heat quickly. Had the land been greater than water, the former would have remained frozen for most time of the year.

   

• Oceans play an important role in the water cycle. About 97% of the total water available on the Earth is stored in oceans. Water evaporates from the oceans into the atmosphere. It then condenses and precipitates on the Earth in the form of rainfall, dew, snow etc.