CONTINENTSAND

OCEANS

EARTH’S CONTINENTS• A continent is one of several very large landmasses on Earth. • Seven regions are commonly regarded as continents. • Here are our planets’ continents from largest in size to smallest: • Asia• Africa• North America• South America• Antarctica• Europe• Australia

• In geology, areas of continental crust include regions covered with water.

ASIA• Asia is the Earth's largest and most populous continent, located in the

eastern and northern hemispheres. • Asia covers an area of 44,579,000 square kilometres, about 30% of

Earth's total land area and 8.7% of the Earth's total surface area. • The continent, which has long been home to the majority of the human

population, was the site of many of the first civilizations. • Asia is notable for its overall large size and population, and for unusually

dense and large settlements as well as vast barely populated regions within the continent of 4.4 billion people.

AFRICA• Africa is the world's second-largest and second-most-populous continent. At

about 30.3 million km², it covers six percent of Earth's total surface area and 20.4 percent of its total land area.• With 1.1 billion people as of 2013, it accounts for about 15% of the world's

human population.• The continent is surrounded by the Mediterranean Sea to the north, both

the Suez Canal and the Red Sea along the Sinai Peninsula to the northeast, the Indian Ocean to the southeast, and the Atlantic Ocean to the west. • The continent includes Madagascar and various archipelagos. It contains 54

fully recognized sovereign states (countries), nine territories and two de facto independent states with limited or no recognition.• Africa's population is the youngest amongst all the continents; the median

age in 2012 was 19.7, when the worldwide median age was 30.4.

NORTH AMERICA• North America is a continent entirely within the Northern Hemisphere and

almost all within the Western Hemisphere. • It can also be considered a northern subcontinent of the Americas.• It is bordered to the north by the Arctic Ocean, to the east by the Atlantic

Ocean, to the west and south by the Pacific Ocean, and to the southeast by South America and the Caribbean Sea.• North America covers an area of about 24,709,000 square kilometers, about

16.5% of the earth's land area and about 4.8% of its total surface. • North America is the third largest continent by area, following Asia and Africa,

and the fourth by population after Asia, Africa, and Europe.• In 2013, its population was estimated at nearly 565 million people in 23

independent states, or about 7.5% of the world's population, if nearby islands (most notably the Caribbean) are included.

SOUTH AMERICA• South America is a continent located in the Western Hemisphere, mostly in the

Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. It is also considered a subcontinent of the Americas.• It is bordered on the west by the Pacific Ocean and on the north and east by

the Atlantic Ocean; North America and the Caribbean Sea lie to the northwest.• South America has an area of 17,840,000 square kilometres. • Its population as of 2005 has been estimated at more than 371,090,000. • South America ranks fourth in area (after Asia, Africa, and North America) and

fifth in population (after Asia, Africa, Europe, and North America). • Brazil is the most populous South American country, with more than half of the

continent's population, followed by Colombia, Argentina, Venezuela, Peru.

ANTARCTICA• Antarctica is Earth's southernmost continent, containing the geographic

South Pole. It is situated in the Antarctic region of the Southern Hemisphere, almost entirely south of the Antarctic Circle, and is surrounded by the Southern Ocean. At 14,000,000 square kilometres, it is the fifth-largest continent in area after Asia, Africa, North America, and South America. • Antarctica is nearly twice the size of Australia. About 98% of Antarctica is

covered by ice that averages 1.9 km in thickness, which extends to all but the northernmost reaches of the Antarctic Peninsula.• Antarctica, on average, is the coldest, driest, and windiest continent, and has

the highest average elevation of all the continents.• Antarctica is a desert, with annual precipitation of only 200 mm along the

coast and far less inland. The temperature in Antarctica has reached −89.2 °C.

EUROPE• Europe is a continent that comprises the westernmost part of Eurasia.• Europe is bordered by the Arctic Ocean to the north, the Atlantic Ocean

to the west, and the Mediterranean Sea to the south. • Europe is the world's second-smallest continent by surface area, covering

about 10,180,000 sq km (2% of Earth's surface; 6.8% land area). • Of Europe's approximately 50 countries, Russia is the largest and most

populous, spanning 39% of the continent and comprising 15% of its population, while Vatican City is the smallest both in terms area and population. • Europe is the third-most populous continent after Asia and Africa, with a

population of 739–743 million or about 11% of the world's population.

AUSTRALIA• Australia, sometimes known as Sahul, Australinea or Meganesia, is a

continent comprising mainland Australia, Tasmania, New Guinea, Seram, possibly Timor, and neighbouring islands.• It is the smallest of the seven traditional continents in the English

conception. • New Zealand is not part of the continent of Australia, but of the

separate, submerged continent of Zealandia.• New Zealand and Australia are both part of the wider regions known as

Australasia and Oceania. • The term Oceania is often used to denote the region encompassing the

Australian continent and various islands in the Pacific Ocean that are not included in the seven-continent model.

EARTH’S OCEANS• An ocean is a body of saline water that composes much of a planet's

hydrosphere.• On Earth, an ocean is one of the major conventional divisions of the

World Ocean, which covers almost 71% of its surface. • These are, in descending order by area:• Pacific• Atlantic• Indian• Southern (Antarctic)• Arctic

THE PACIFIC OCEAN• The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends

from the Arctic Ocean in the north to the Antarctica in the south and is bounded by Asia and Australia in the west and the Americas in the east.• At 165 million km2 in area, this largest division of the hydrosphere—

covers 46% of the Earth's water surface and about one-third of its total surface area, making it larger than all of the Earth's land area combined.• The equator subdivides it into the North Pacific Ocean and South Pacific

Ocean, with two exceptions: the Galápagos and Gilbert Islands, while straddling the equator, are deemed wholly within the South Pacific.• The Mariana Trench in the western North Pacific is the deepest point in

the world, reaching a depth of 10,911 metres.

THE ATLANTIC OCEAN• The Atlantic Ocean is the second largest of the world's oceanic divisions,

following the Pacific Ocean. With a total area of about 106,400,000 square kilometres, it covers 20 percent of the Earth's surface and about 29 percent of its water surface area. Its name refers to Atlas of Greek mythology, making the Atlantic the "Sea of Atlas". The oldest known mention of "Atlantic" is in The Histories of Herodotus around 450 BC - Atlantis Thalassa (Sea of Atlas). • Before Europeans discovered other oceans, their term "ocean" was

synonymous with the waters beyond the Strait of Gibraltar that are now known as the Atlantic. The early Greeks believed this ocean to be a gigantic river encircling the world. • The greatest depth, Milwaukee Deep with 8,380 metres, is in the Puerto

Rico Trench.

THE INDIAN OCEAN• The Indian Ocean is the third largest of the world's oceanic divisions,

covering 70,560,000 km2 (20% of the water on the Earth's surface).• It is bounded by Asia on the north, on the west by Africa, on the east by

Australia, and on the south by the Southern Ocean.• It is named after the country of India.• The Indian Ocean is known as Ratnākara, "the mine of gems" in ancient

Sanskrit literature, and as Hind Mahāsāgar, "the great Indian sea", in Hindi.• Its maximum depth is 7,906 m.

THE SOUTHERN OCEAN• The Southern Ocean, also known as the Antarctic Ocean or the Austral

Ocean, comprises the southernmost waters of the World Ocean, generally taken to be south of 60° S latitude and encircling Antarctica.• As such, it is regarded as the fourth-largest of the five principal oceanic

divisions: smaller than the Pacific, Atlantic, and Indian Oceans but larger than the Arctic Ocean.• This ocean zone is where cold, northward flowing waters from the

Antarctic mix with warmer subantarctic waters.• By way of his voyages in the 1770s, Captain James Cook proved that

waters encompassed the southern latitudes of the globe. • The Southern Ocean's greatest depth of 7,236 m occurs at the southern

end of the South Sandwich Trench.

THE ARCTIC OCEAN• The Arctic Ocean (also known as the Northern Ocean), located in the

Northern Hemisphere and mostly in the Arctic north polar region, is the smallest and shallowest of the world's five major oceanic divisions.• The Arctic Ocean can be seen as the northernmost part of the oceans of

our planet.• The Arctic Ocean has a total volume of 1.3% of the World Ocean.• The deepest point is Litke Deep in the Eurasian Basin, at 5,450 m.