Oceans and Seas
The oceans are large portions of salt water, which
separate the continents and occupy approximately 71% of the
earth's surface. Yuri Gagary's mention that “the earth is
blue” is due to the immense amount of water on the planet.
The most used division for this water area is in five
oceans: Pacific, Atlantic, Indian, Arctic Glacier and
Not every portion of water is called an ocean: there are
seas, canals, gulfs, etc. The differences between each of
them are linked to their shape, location and, in the case of
the ocean, their salinity. Much of this area is more than
3000 meters deep; therefore, they are not yet well explored.
The ocean is still an area that man has not fully explored.
Oceans are important for the maintenance of life, as they
affect the climate. The water absorbs the heat of the sun
and with the hot and cold currents of the ocean, the
temperatures of the coastal regions change and rains and fog
What is the difference between Oceans and Seas?
The difference between seas and oceans is in their
territorial extension. The former are smaller, located in
coastal areas and linked directly or indirectly with the
oceans. Among the types of seas there are the open
seas, which have a greater connection with the
oceans; the continental seas, which have a
limited connection; and closed seas, which
are related to the oceans only indirectly, through rivers
and channels. The oceans are bigger.
The Pacific Ocean has this name because
it is a calmer ocean to navigate than the Atlantic. This
“baptism” was performed by Fernão Magalhães, Portuguese
navigator, approximately in 1520. The Pacific Ocean is the
largest ocean on earth in extension with approximately 180
million km² of aquatic mass and represents one third of the
planet. Of all the oceans, it is one of the deepest and,
therefore, one of the least explored, with more than 80% of
its waters below 3000 meters.
It is located between the American continent, Australia,
Asia and Antarctica. A "peculiar" feature of the Pacific
Ocean is the large number of volcanoes that exist due to the
Pacific Tectonic Plate, which is linked to the tectonic
plates of the Philippines, Eurasian, Indian, Nazca and the
North American plate.
Because of all these plates together, and their friction,
many volcanoes and earthquakes happen in the Pacific Ocean.
Another major incidence in the Pacific is that of the seas:
large seas are connected to the Pacific such as the Sea of
Japan, the Sea of Corals, the Sea of Java, among
The Atlantic Ocean is the second largest
ocean on the globe and is located between the American,
African and European continents, having a letter "S" format.
Its name comes from the mythological deity "Atlas", a Titan
that would have been the first king of the city, also
mythological of Atlantis. Atlas was later ordered, by Zeus,
to carry the heavens forever.
The Atlantic Ocean occupies around 17% of the earth's
surface and 26% of the area occupied by water on the planet.
Its length is around 106,400,000 km². In its interior there
is the meso-oceanic mountain range, resulting from the
friction between the South American tectonic plates and the
African plate. Check
Countryaah for detailed information about South America.
Despite not being the largest ocean, it is the one that
is linked to more countries, including Brazil. Because it
was linked to the great powers of maritime expansion, which
occurred in the commercial revolution in the 15th to 18th
centuries, the ocean was navigated to the first existing
trade routes, such as Portugal to the Indies and Brazil.
Of all the oceans it is the most salty, the second in
extension and the one that bathes the most countries. The
highest temperatures in this ocean are close to the Equator
and reach 30 ºC, while the lowest are around -2 ºC, in
winter, close to the Antarctic Ocean. Its greatest depth is
located in the Puerto Rico Pit, reaching 8,605 meters.
The third largest ocean in the world is the
Indian Ocean. It is located between the African,
Asian, Antarctic continent and also with Australia and
Indonesia. It has an area of approximately 73,556,000 km²,
less than half the area of the largest Ocean, the Pacific.
Its greatest depth is about 7,455 meters, located in the
Java pit. Its highest temperature is
registered in the area of the Persian Gulf and Red Sea,
reaching 32 º C. On the other hand, the low temperatures are
on the border with the Antarctic Ocean, of -1 ºC.
This ocean has a high economic importance: it supplies
the consumption of fish and shrimp from Asia and for export,
it serves as a route for oil coming from the Persian Gulf
and Indonesia, the great amount of oil that it shelters
besides the many ores that are obtained in that ocean. As it
is a much calmer ocean than the Atlantic and the Pacific, it
is preferred for making commercial routes, as they are
easier to navigate.
Being composed of the waters that bathe the Antarctic
continent, the Antarctic Ocean is only
ahead of the Arctic Ocean in extension. There are about
20,327,000 km². It is the only one that can circle the
entire planet, forming a complete circle. It is also the
"newest", since it was officially recognized in 2000 by the
International Hydrographic Organization, which determined
its limits, which are even the same as those of the Arctic
Both the ocean and the Antarctic continent are used for
peaceful and research purposes by countries like France, New
Zealand, South Africa, the United States and Brazil. It
houses more than 80% of the world's fresh water. Its highest
depth is around 5,000 meters. Its average temperature varies
between 10 degrees positive and -2 degrees. Due to its
climatic conditions, the ocean is hit by storms and strong
winds. Its waters have not yet been fully explored, nor has
A curious detail is that this ocean has the largest
current in the world: the Antarctic Circumpolar Current,
which always moves eastward.
The smallest is the Arctic Ocean. It is
located in the northern hemisphere between the countries:
Canada, Norway, Sweden, Finland, Iceland and Russia. Its
greatest depth is 4 km, being the shallowest among the
oceans. Its area is approximately 14,056,000 km².
It is not so salty due to the low evaporation that occurs
in the areas around it and the large amount of fresh water
that circulates in its environment. Its temperature does not
vary much, being always close to 0 ºC. Despite being
classified as an ocean, it is limited for fishing and sea
transport, due to the low temperatures.
Defrost and Global Warming
The melting is a phenomenon caused by global warming,
triggered by the intensification of the greenhouse effect,
where ice melts in the Arctic and other parts of the world.
Global warming is a phenomenon that brings about an increase
in the average temperatures of the Earth, in addition to
Since 1996 there has been a decrease in ice on Earth.
Among the main areas affected by the phenomenon are the
Arctic, Greenland, Antarctica and several mountain ranges.
In addition, if this melting continues, it will cause an
environmental imbalance and harm many marine species, such
as walruses, whales, polar bears, among other animals;
Populations living in coastal areas will also suffer from
the melt, as there will be a considerable increase in water
in the oceans. According to scientists and some NASA
research, the melting process in Greenland intensified in
2004. If there is a considerable increase in the temperature
of the Earth, it will be more common to see the formation of
lakes in the interior of that territory.