Three quarters of the Earth are made up of water, only a small portion is made up of land surface. Therefore, the amount of water on the planet is abysmally large and there are two concepts that we use to refer to salty water bodies. However, they are often used indiscriminately, although it should be noted that there is a difference between ‘sea’ and ‘ocean’.
Difference Between Sea and Ocean
The most marked difference lies in the extent of water in both bodies. The seas are smaller and are located close to the land surfaces, that is, they are the water bodies adjacent to the mainland. Although it should be noted that they are part of the oceans, the Caribbean Sea, for example, cannot be separated from the Atlantic Ocean, since one is part of the other.
By contrast, the oceans are much larger bodies with millions of square kilometers in area. In addition, the seas are closed so their depth tends to be less, while the oceans are open and reach maximum depths. It could be said that the oceans are more complex because they behave as functional units, they present deep sea currents necessary to maintain planetary balance.
The Atlantic current is a clear example of this, since it is responsible for transporting warm water to the south and bringing ice water to the Arctic. Unfortunately, as a result of global warming, these types of ocean currents are undergoing modifications, affecting marine ecosystems that completely depend on them.
How many oceans are there?
In total there are five oceans around the globe that are of great importance for the subsistence of marine life, as they host important ecosystems in them. They are classified according to their size, the so-called large oceans that are the Pacific Ocean, the Atlantic, and the Indian Ocean. And those classified as minor are the Arctic and Antarctic oceans.
The Pacific Ocean is the largest of all, occupying a third of the global ocean. It opens from the Arctic to the Antarctic and extends from Indonesia to the coast of Colombia. It almost crosses from pole to pole and covers a total area of 155 million 557 square kilometers. They are followed by the Atlantic, which, curiously, is the youngest of all, since it was formed about 200 million years ago with the division of the supercontinent known as Pangea. It is in charge of separating the American continent from Europe and Africa. In third place is the Indian Ocean, which gets its name from the fact that it covers the coasts of India. They are followed by the Arctic and the Antarctic, which play a fundamental role in regulating the planet’s temperature.
How many seas are there?
According to the International Hydrographic Organization, there are about 60 seas on planet Earth. The most important being the Arabian Sea, the South China Sea, the Caribbean Sea, the Mediterranean Sea and the Bering Sea, because they are the largest in the world.
It should be noted that not all seas belong to the oceans. Well, there are some like the Dead Sea, the Caspian Sea and the Aral Sea that are actually large salt lakes.
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