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 aqueous 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 extension of both bodies. The seas are smaller and are located close to land surfaces, that is, they are the aqueous bodies adjacent to dry land. 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.
In contrast, oceans are much larger bodies with millions of square kilometers of surface area. Furthermore, the seas are closed so their depth tends to be shallower, 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 the clear example of this, as it is responsible for transporting warm water to the south and bringing frozen water to the south. Unfortunately, as a result of global warming, these types of ocean currents are undergoing modifications, affecting mariners who 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 house important ecosystems. The so-called large oceans are classified according to their size, which are the Pacific, Atlantic, and Indian Oceans. And those classified as minor, which are the Arctic and Antarctic oceans.
The Pacific Ocean is the largest of all, occupying one third of the global ocean. It opens from the Arctic to Antarctica 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 is curiously the youngest of all since it was formed about 200 million years ago with the division of the supercontinent known as Pangea. It is responsible for separating the American continent from the European and African continents. In third place is the Indian Ocean, which gets its name because it covers the coasts of India. They are followed by the Arctic and 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 Southern 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.