To celebrate World Oceans Day on June 8, the National Geographic Society decided to add a fifth ocean to its list of officially recognized oceans.
Oceans cover 71 percent of the Earth’s mass and are technically one large body of water, but oceanographers have previously divided it into four: the Atlantic, the Pacific, the Indian, and the Arctic oceans. Now, National Geographic recognizes the water that surrounds the continent of Antarctica (beyond the 60° South latitude) as the Southern Ocean.
“Anyone who has been there will struggle to explain what’s so mesmerizing about it, but they’ll all agree that the glaciers are bluer, the air colder, the mountains more intimidating, and the landscapes more captivating than anywhere else you can go,” said Seth Sykora-Bodie, a marine scientist at the National Oceanic and Atmospheric Administration (NOAA) and a National Geographic Explorer to National Geographic.
While this is new for the National Geographic Society, a non-profit scientific and educational organization that has been designing maps and atlases since 1915, it’s not unheard of. The US Board of Geographic Names already recognized the Southern Ocean. Still, there has been international debate about whether or not the waters around Antarctica were distinct enough to be considered an ocean. National Geographic Society Geographer Alex Tait describes the debate as “geographic nerdiness.”
The Southern Ocean is distinguished by the Antarctic Circumpolar Current (ACC) from when Antarctica separated from South America 34 million years ago, making Antarctica’s water “colder and slightly less salty.” The ACC has also caused thousands of distinctive species to live in those waters and nowhere else in the world, according to National Geographic.
“We think it’s really important from an educational standpoint, as well as from a map-labeling standpoint, to bring attention to the Southern Ocean as a fifth ocean,” Tait told The Washington Post. “So when students learn about parts of the ocean world, they learn it’s an interconnected ocean, and they learn there are these regions called oceans that are really important, and there’s a distinct one in the icy waters around Antarctica.”