Water occupies more than 71% of the earth’s surface and is present in the oceans, rivers and lakes ice in glaciers, underground water and water vapour in the air. All the water present on the earth’s surface together forms the hydrosphere.
More than 97% of water is in the oceans and seas. Ocean water contains large quantities of dissolved salts and is not fit for drinking. A little less than 3% of water is in the form of glaciers. Only 0.03 per cent of water is available as fresh water.
Oceans form a major portion of the earth’s hydrosphere. The major oceans found on the earth’s surface are Pacific ocean, Atlantic ocean, Indian Ocean and the Arctic ocean. The three main movements of water are waves, tides and ocean currents.
An important fact to note is that all the oceans are interconnected. The Pacific Ocean is the largest of all the oceans and covers one-third of the earth’s surface. It is surrounded by the continents Asia, Australia, North America, and South America.
The Atlantic Ocean is the second largest. It has the continents of North and South America on the western side and Europe and Africa on the eastern side. The Indian Ocean, it is named after our country India and is triangular in shape. It has the continents of Asia on the north, Africa on the west and Australia on the east.
The Arctic Ocean is the smallest ocean and surrounds the North Pole. It is connected to the Pacific Ocean by a narrow stretch of shallow water known as the Bering Strait.