The Antarctic Ocean, or the Southern Ocean, is the last ocean to be designated as such. Indeed, not all countries and researchers recognize it even though the U.S. Board on Geographic Names and the International Hydrographic Organization recognizes it already. Its limits were defined by this organization in 2000 but need confirmation from most oceanic agencies and administrations.

It differs from the other oceans as it is the only one that surrounds a continent. It comprises the waters located in the southern hemisphere, whose boundaries are the Antarctic Convergence or latitude 60° south and the Antarctica coast. It covers all the 360° of longitude. It connects the principal southern oceanic basins as well as the sea surface with deeper layers of water.

The Antarctic Ocean, has an area of about 21.96 million square kilometers and includes:

– the Weddell Sea,
– the Lazarev Sea,
– the Riiser-Larsen Sea,
– the Amundsen Sea,
– the Cosmonauts Sea,
– the Cooperation Sea,
– the Davis Sea,
– the Bransfield Strait,
– part of the Drake Passage,
– the D’Urville Sea,
– the Somov Sea,
– part of the Scotia Sea, and
– the Ross Sea.

This ocean has the largest ocean current, called the Antarctic Circumpolar Current.

Properties of the Antarctic Ocean.

This ocean has the largest ocean current, called the Antarctic Circumpolar Current, and since it connects the Pacific, Atlantic, and Indian Ocean basins, it influences the climate of the entire planet. It takes 135-145 million cubic meters of water per second from west to east along 20,000 Antarctic kilometers at a speed of 0.5 meters per second. This current distributes heat and influences rainfall patterns and temperatures.

Properties of the Antarctic Ocean.
Antarctic Ocean.

It has an average depth of 4000-5000 meters and touches around 17,968 kilometers of Antarctic coastline. A continental shelf about 260 kilometers wide and a maximum of 2600 kilometers lies beneath this ocean. 
Its temperature ranges between 10°C and -2 °C, but it has the strongest winds and waves in the world, as the temperature of the ice contrasts the open ocean. During winter, the sea freezes at a latitude 65° south at the Pacific and a latitude 55° south in the Atlantic Ocean sector. During winter most coastal waters are frozen except in some areas.

Salinity is lower in the north, near the Antarctic Convergence where the colder waters flow below, the less cold waters of the Antarctic convergence. This ocean is a huge deposit of carbon and contains about 50 times more than the atmosphere.

Economic Importance of the Southern Ocean.

Due to the low levels of iron and sunlight, productivity is not high. It is rich in nutrients and manganese nodules as well as possible oil and natural gas deposits. It is also home to over 10,000 species, all perfectly adapted to the weather conditions, such as penguins, squids, whales, seals, krill, and a variety of fish.

Fishing is relatively fruitful, being krill and hake the most caught species. Between 2006-2007 for example, 126,976 metric tons of these species were captured.

Illegal fishing affects the sustainability of the sea and reduces the availability of food for other species.

In the Antarctic territory, there are two seaports: McMurdo and Palmer. Offshore, there are a few anchor points. Not all the waters of this ocean are navigable due to the presence of ice blocks. Only a few research boats cross the latitude 60° South since neither private nor commercial navigation is allowed.

Conservation of the Antarctic Ocean.

The increase of ultraviolet radiation, as a result of the ozone hole, is a major concern. The ice whiteness reflects the heat and bounces it back into space, which increases the cold. Some experts think that ultraviolet radiation is responsible for the reduction of phytoplankton, the primary link in the food chain. Besides, illegal fishing affects the sustainability of the sea and reduces the availability of food for other species.

Some organizations implemented guidelines to diminish the abuse of its natural resources. For example, the International Whaling Commission prohibits whaling below latitude 40° South.

Quick facts:

• It covers 20 percent of the surface of all oceans and 4.3 percent of the face of the earth.
• Its narrowest part is the Drake Passage, which has only about 1000 kilometers wide between South 
America and Antarctica.
• It’s the fourth largest ocean.
• The maximum depth corresponds to the South Sandwich Trench, which is 7,235 meters deep.
• The Antarctic Circumpolar Current carries 150 times more water than the flow of all the rivers 
in the world.

Ocean, the source of life.

The Ocean is an immense body of water that covers more than 70 percent of planet Earth, and it is possibly the home of the first living organisms. The ocean is a unique, full of natural resources, resplendent beauty, strange and ordinary life, and valuable resources.

Ocean is the name given to a body of saline water larger in size than a sea. The world’s ocean contains about 1.35 billion cubic kilometers of water and represents about 97 percent of all the water on Earth, although more than 95 percent of what exists underwater is still unexplored and a mystery to us.

Arctic ocean
Pacific ocean
Atlantic ocean
Indian ocean
Antarctic ocean

For research, study, and investigation, the ocean is split into five parts that most people know: the Pacific Ocean, the Atlantic Ocean, the Indian Ocean, the Arctic Ocean, and the Antarctic Ocean. Historically, the first four have been mapped and recognized by most countries, but now the Antarctic is gaining more international recognition. The Indian, Pacific and Atlantic oceans are called “the three great oceans” and their navigation and exploration date back to the early civilizations.

Characteristics of the oceans.

After Earth’s formation, around 4.5-4.6 billion years ago, lighter rocks rose to form Earth’s crust while heavier ones sank and settled to form the mantle and core of the planet. While the molten rock cooled, the water vapor inside was expelled along with other gasses; at some point, the steam condensed and formed an ocean, which over the years became the one that touches the shores today.

Although there are many theories about the beginning of life, most scientists agree that the ocean hosted the initial forms of life, which were the ancestors of all life that now exist, including humans. One of the most considered hypotheses indicates that living organisms originated near a hydrothermal vent in the ocean, given the chemical and energy characteristics that exist there. Many marine species are considered primitive or “living fossils” because they have not evolved much over thousands or millions of years and greatly resemble species that lived in ancient times.

Ocean resources.

Even today there may be species with ancient origins. Marine life is vast, diverse, and surprising. Many biologists believe that between 500 thousand to five million marine species are not discovered yet, and less than five percent of the ocean has been explored.

Each ocean has own temperatures, salinity, and specific natural resources, but all of them have seamounts, ridges, animal and plant species, minerals, and other resources. The ocean is home to the largest animals in the world, like the blue whale, and tiny creatures like plankton and krill. Fish exist in vast quantities, and many of them serve as food for humans and marine and land species.

The ocean is home to the largest animals in the world, like the blue whale, and tiny creatures like plankton.

Although the oceans provide us a set of useful natural resources, they are also prone to suffer damage: overfishing, pollution, endangered marine species, etc. It is important to take care of the aquatic ecosystems because damaging them can impact and have grave consequences for all living beings on the planet.

Interesting? If so, you can learn details about each ocean and everything about them, with concise information that will take you step by step through aquatic life.

The Atlantic Ocean is a huge mass of water covering about 16.7 percent of the Earth and a total area of approximately 85,133,000 square kilometers. To have an idea of its size, it is slightly larger than half of the Pacific Ocean.

This ocean has an average depth of 3,339 meters with adjacent seas, and its volume is 354,700,000 cubic kilometers. Milwaukee Deep is the deepest area, with 8,380 meters.

Its boundaries are the Arctic Ocean in the north, the Pacific Ocean in the southwest, the Indian Ocean in the southeast, and the Southern or Antarctic Ocean in the south. It connects to the Arctic Ocean through the Greenland Sea, the Denmark Strait, the Norwegian Sea and the Barents Sea. Regarding land, it reaches the shores of America in the west and Europe and Africa in the east. The Atlantic Ocean includes the Baltic Sea, the Black Sea, the Caribbean Sea, the Mediterranean Sea, the Gulf of Mexico, and the Norwegian Sea.

The Atlantic is the saltiest ocean in the world.

The northernmost waters sink because they are colder, denser, and saltier than normal due to being cooled by Arctic currents; this creates what is known as “thermohaline circulation” or the “ocean conveyor belt.”

The name Atlantic comes from Atlas, a character from Greek mythology known for holding up the sky on his shoulders.

Properties of the Atlantic Ocean.
Waters of Atlantic Ocean.

Properties of the Atlantic Ocean.

The Atlantic is the saltiest ocean in the world; however, the surface salinity varies with latitude and season. Thus, the saltier waters are at a range of latitude from 25° north to 25° south and in tropical areas of low rainfall and high evaporation. The lowest levels of salinity occur north of the equator.

Temperatures can vary depending on the latitude and the season, but they are about -2 °C. Again, north of the equator, the warmest temperatures are registered while the coldest are in the Polar Regions. Between August and November, hurricanes are common, tending to develop along the coasts of Africa and moving westward into the Caribbean Sea.

The ocean floor is relatively flat but has abyssal plains, ridges, depressions, plateaus, and canyons. In the Labrador Sea, the Denmark Strait, and the coast of the Baltic Sea, the water is usually covered with lots of ice packs between October and June.

Economic Importance of the Atlantic Ocean.

The Atlantic Ocean is the main communication link between Europe and America and has been sailed for many centuries. It has a considerable vessel traffic. At the same time, it has significant oil and natural gas deposits in the sedimentary rocks of the continental shelves, especially in the Caribbean Sea, the Gulf of Mexico, and the North Sea.

The Atlantic is exploited for fisheries, sand, gravel, poly-metallic nodules, and gemstones.

Besides oil and gas, the Atlantic is exploited for fisheries, sand, gravel, poly-metallic nodules, and gemstones. Fishing is plentiful, and the most important fishes are cod, hake, herring, and mackerel.

Conservation of the Atlantic Ocean.

Oil spills pollute the Atlantic Ocean; water drain with toxic substances, and garbage. Some international treaties are concerned about this and have joined forces to reduce the effects. However, many animal species are already endangered such as the manatee, some whales and turtles, sea lions, and seals.


Quick Facts:

• It’s the world’s second largest ocean.
• Among the five oceans, it is probably the last formed on Earth.
• The Ancient Greeks believed that it was an enormous river encircling the world.
• Sometimes, it is called “black Atlantic” for the role it served in the history of dark-skinned 
people, who often traveled from Africa to America by sea.
• In 2013, a crack in the earth’s crust was discovered, it marks the future 
union of the American and European continents and the disappearance of this ocean in about 220 million years.



The Indian Ocean is the third largest, after the Atlantic and the Pacific Oceans. It extends over approximately 9,978 kilometers from southern Africa to Western Australia and is almost six times the size of the United States. Its boundaries include Asia in the north, Africa in the west, Australia in the east, and the Antarctic or the Southern Ocean in the south.

This body of water covers about 19.5 percent of the total water on Earth, or in other words, one-fifth. It covers 13.8 percent of the Earth’s surface. It has an area of 70.56 million square kilometers and includes:

– the Andaman Sea,
– The Arabian Sea,
– the Bay of Bengal,
– the Flores Sea,
– the Great Australian Bight,
– the Gulf of Aden,
– the Gulf of Oman,
– the Java Sea,
– the Mozambique channel,
– the Persian Gulf,
– the Red Sea,
– the Savu Sea,
– the Strait of Malacca, and
– The Timor Sea.

It connects with the Mediterranean Sea through the Suez Canal.

Its volume is 292,131,000 cubic kilometers. Its average depth is around 3,890 meters, and its deepest point is the Java Trench or Sunda Trench, measuring between 7,258 and 7,725 meters. However, sometimes it is mentioned that the Diamantina Trench is the deepest part of this ocean, slightly deeper, about 8,047 meters.

The highest level of salinity is in the Arabian Sea and along a belt of water.

Properties of the Indian Ocean.

Madagascar. Waters of Indian Ocean.

The water salinity in the Indian Ocean is between 3.2 and 3.7 percent. The highest level of salinity is in the Arabian Sea and along a belt of water located between southern Africa and southwestern Australia. It is common to see icebergs at latitude 65° south throughout the year, but their limit is latitude 45° south.

Its surface temperature at latitude 20° south is about 22°C, while in the east can exceed 28°C. From latitude 40° south, water temperatures decrease. Incoming flows from the Atlantic Ocean, the Red Sea, and Antarctic currents control the circulation of water, but the ocean has two basic flow patterns: the northern hemisphere current, which moves to the right, and another stream south of the equator, which moves in the opposite direction.

The weather is variable. North of the equator, it is dominated by a monsoon climate, but in the southern hemisphere, winds are weaker, with occasional summer storms that hit the Mauritius Island. From October to April, there are high winds in the Northeast. The monsoon season causes cyclones that can batter the Bay of Bengal and the Arabian Sea.

This ocean is more recent than the others, so there are crags and ridges in its floor. The South Kerguelen Plateau, a small underwater continent of volcanic origin, is in the south. In the west and near Madagascar, there is an underwater plateau whose length is 2,000 kilometers.

Economic Importance of the Indian Ocean.

The Indian Ocean contains a significant amount of oil and natural gas and is also a source of fish, sand, and metal, relevant to different industries. It has four main waterways: Bab-el-Mandeb, the Strait of Hormuz, the Straits of Malacca, and the Suez Canal.

40 percent of the world’s offshore oil production has its origin in the Indian Ocean.

Marine life is relatively limited in the Indian Ocean due to lower concentrations of phytoplankton. However, the northern part of this ocean is home to a larger number of species, which are essential for human consumption. Fishing fleets from Russia, Japan, Taiwan and South Korea navigate this ocean catching shrimp and tuna.

Moreover, there is a continuous traffic carrying oil from Indonesia and the Persian Gulf, with an average of 17 million barrels of oil per day. In fact, 40 percent of the world’s offshore oil production has its origin in the Indian Ocean.

Conservation of the Indian Ocean.

In the late 90’s, a huge quantity of trash was found, suspended on the surface of the Indian Ocean. Thousands of plastic particles, chemical substances, and other garbage are concentrated there, covering about 10 million square kilometers. Meanwhile, the Arabian and Red Seas and the Persian Gulf are contaminated with hydrocarbons from oil and gas.

The ocean is home to some endangered species: the dugong, whales, seals, and turtles.


Quick facts:

• It is the warmest ocean basin on Earth.
• Annually, more than 7,000 humpback whales travel to the waters of Madagascar to breed and give birth.
• The world’s earliest civilizations developed around the Indian Ocean.
• In Sanskrit literature, it is known as “Ratnakara” which means “gemstone mine.”