The earth now has five oceans instead of four

The Atlantic, Pacific, Indian and Arctic oceans - and what name do you think the new addition will go by? For more than 100 years, geographers disagreed about the existence of a fifth ocean.

Every child learns in school that our planet has four large oceans: the Atlantic, Pacific, Indian and Arctic Oceans cover 71 percent of the Earth with water. Now a fifth world ocean has joined them: the Antarctic or Southern Ocean.

Back in February, the U.S. National Oceanic and Atmospheric Administration (NOAA) categorized the approximately 20,327 million square kilometer sea surrounding the Antarctic continent as an ocean. This makes it the second smallest ocean in the world after the Arctic Ocean. At its deepest point, the sea area measures 5805 meters to the ocean floor.

Until now, however, it has only appeared on a few maps under its designation. This is now set to change. The U.S. publisher National Geographic has been publishing maps and atlases since 1915 - but until now, they have only ever included four oceans. Now the map maker also wants to mention the Antarctic Sea by name.

The fact that this is only happening now, although NOAA has already been officially listing the Antarctic Ocean as a world ocean since February, has a symbolic reason: The publisher announced the innovation just in time for World Oceans Day on June 8. This would change the world view of many generations of schoolchildren in the future, as geographer Alex Tait explained to National Geographic:

"Until the Southern Ocean is included, students won't learn about its features and why it's so important."

Alex Tait, Geographer

For more than a century, cartographers around the world have debated the existence of a fifth ocean. For a long time, geographers disagreed on whether the waters surrounding Antarctica had enough peculiarities to pass for a true world ocean. Although several researchers have already come to the conclusion that the Southern Ocean is definitely one of the great seas of this planet, it has not been officially recognized by any international treaty or institution as of the beginning of this year.

The last time such an attempt was made by the International Hydrographic Organization (IHO) was in 2000. The organization establishes international ocean boundaries. When its 68 member states were asked whether the Southern Ocean should be recognized as a world sea, only 28 responded. Twenty-seven were in favor of defining it as a world ocean, with only Argentina opposed. Another point of contention was where the boundary should be: While half of the members who spoke out voted for the 60th parallel, others, such as Australia, argued that the ocean should begin at the 50th parallel. For this reason, the Southern Ocean has so far only been considered a maritime area by the IHO.

The four previous oceans are defined by the boundaries of their respective continents: The Atlantic Ocean is located between the Americas, Europe, and Africa; the Indian Ocean is located between Africa as well as Australia, and is bounded to the north by Asia. The Pacific Ocean is located between America and Asia, the Arctic Ocean north of the adjacent continents of Asia, Europe and North America.

The Antarctic Ocean is cooler and less saline than other oceans.