The Earth looks blue when we see it from space. This is because, two-thirds of it is covered by water. The water is found in oceans and seas. Oceans are vast expanse of water. Seas are water bodies partially or fully enclosed by land. As you have studied previously, there are five main oceans in the world.
1. The Pacific Ocean
The Pacific Ocean is the largest and deepest ocean on the Earth. It covers about one-third of the Earth’s total area and spreads for about 168.72 million sq.km.
It is bounded by Asia and Australia in its west and North America and South America in its east. It stretches from the Arctic Ocean in the north to the Southern Ocean in the south.
If Mount Everest, which is the highest point (8,848 metres)was plugged into the Mariana Trench, still there would be 2,146 metres of water left. The depth in meters from mean sea level is denoted as m-
This ocean’s shape is roughly triangular with its apex in the north at the Bering Strait which connects the Pacific Ocean with the Arctic Ocean. The Bering Sea, the China Sea, the Sea of Japan, Tasman Sea and the Philippine Sea are some of the marginal seas of the Pacific Ocean. Indonesia, Philippines, Japan, Hawaii, New Zealand are some of the islands located in this Ocean. The deepest point Mariana Trench is 10,994 m- and is located in the Pacific Ocean. A chain of volcanoes is located around the Pacific Ocean called the Pacific Ring of Fire.
The Spanish navigator Ferdinand Magellan named the ocean Pacific, meaning calm or tranquil.
2. The Atlantic Ocean
The Atlantic Ocean is the second largest ocean on the Earth. It covers one sixth of the Earth’s total area and spreads for about 85.13 million sq.km . It is bounded by North America and South America in the west and Europe and Africa in the east. Like the Pacific, it stretches from the Arctic Ocean in the north to the Southern Ocean in the south. The shape of the Atlantic Ocean resembles the letter ‘S’. The Strait of Gibraltar connects the
Atlantic Ocean with the Mediterranean Sea. The Atlantic Ocean is the busiest shipping route between the Eastern and Western hemispheres. The deepest point is the Milwaukee Deep in the Puerto Rica Trench. It has a depth of about 8600 m-. The Caribbean Sea, the Gulf of Mexico, the North Sea, the Gulf of Guinea and the
HOTS: Why are the Red Sea, Dead Sea and Black Sea named so?
Mediterranean Sea are important marginal seas of the Atlantic Ocean. St. Helena, Newfoundland, Iceland and Falkland are some of the islands found in this ocean.
3. The Indian Ocean
The Indian Ocean is the third largest ocean on the Earth’s surface. It covers an area of about 70.56 million sq.km. It is named after India. It is triangular in shape and bounded by Africa in the west, Asia in the north and Australia in the east. The Andaman and Nicobar Islands, Lakshadweep, Maldives, Sri Lanka, Mauritius and the Reunion Islands are some of the islands located in the Indian Ocean. Malacca strait connects the Indian Ocean and the Pacific Ocean.
Palk Strait connects the Bay of Bengal and Palk Bay.
The Bay of Bengal, the Arabian Sea, the Persian Gulf and the Red Sea are some of the important marginal seas of the Indian Ocean. The Java trench (7,725 m-) is the deepest point in the Indian Ocean.
• 6° Channel separates Indira Point and Indonesia
• 8° Channel separates Maldives and Minicoy islands
• 9° Channel separates Lakshadweep Islands and Minicoy islands
• 10° Channel separates Andaman and Nicobar Islands
4. The Southern Ocean
The Southern Ocean surrounds the continent of Antarctica and is enclosed by the 60°S latitude. It covers an area of 21.96 million sq.km. It is bordered by the southern parts of the Pacific, the Atlantic and the Indian Oceans. The Ross Sea, the Weddell Sea and the Davis Sea are the marginal seas of this Ocean.
Farewell Island, Bowman Island and Hearst Island are some of the islands located in this ocean. The water in this ocean is very cold. Much of it is covered by sea ice. The deepest point in this ocean is South Sandwich Trench with a depth of 7,235 m-.
HOTS: When you travel from Japan to California, which ocean would you travel across?
5. The Arctic Ocean
The Arctic Ocean is the smallest ocean. It covers an area of 15.56 million sq.km. It lies within the Arctic Circle. It remains frozen for most of the year. The Norwegian Sea, the Greenland Sea, the East Siberian Sea and the Barents Sea are some of the marginal seas of this ocean. Greenland, New Siberian Island and Novaya Zemlya Island are some of the islands located in the Arctic Ocean.
The North Pole is situated in the middle of the Arctic Ocean. The Eurasian Basin is the deepest point in the Arctic Ocean, which is about 5,449 m- in depth.
HOTS: When you arrange the continents in ascending order according to their size, which ranks third?