“The Fifth Ocean” on Earth 地球“第五大洋”

The Arctic Ocean， Atlantic Ocean， Indian Ocean and Pacific Ocean are the four oceans we learned about in the geography class. But now we have a new ocean.

On the 13th World Oceans Day， whichfell on June 8，2021，the US NationalGeographic Society announced it wouldrecognize the southern ocean inAntarctica， bringing the global total to five.

Unlike the Arctic， Atlantic， Indian and Pacific Oceans—which are defined by the continents that bound them—the Southern Ocean is instead characterized by the Antarctic Circumpolar Current （ACC）. According to National Geographic， the Southern Ocean includes most of the waters surrounding Antarctica out to 60 degrees south latitude.

“Rimmed by the formidably swift ACC， it is the only ocean to touch three others and to completely embrace a continent rather than being embraced by them，” Sylvia Earle， US marine biologist and oceanographer， told Daily Mail.

Those familiar with the Southern Ocean know its unlike any other. “Anyone who has been there will struggle to explain whats so mesmerizing about it， but theyll 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，” Seth Sykora-Bodie， a marine scientist at the US National Oceanic and Atmospheric Administration， told National Geographic.

Due to the ecologically distinct environment of the Southern Ocean， its home to thousands of unique species. The ocean also has wider ecological effects. For example， humpback whales are known to feed on small shrimp off Antarctica during the summer before migrating north to the warmer climates of Central and South America for the colder winter months， according to Daily Mail.

National Geographic hopes their revised maps will bring public awareness to the region， thereby encouraging Southern Ocean conservation—but its significance is beyond that.

“We think its really important from an educational standpoint， as well as from a maplabeling standpoint， to bring attention to the Southern Ocean as a fifth ocean，” Alex Tait， a US National Geographic Society geographer， told The Post. “So when students learn about parts of the ocean world， they learn its an interconnected ocean， and they learn there are these regions called oceans that are really important， and that theres a distinct one in the icy waters around Antarctica.”

北冰洋、大西洋、印度洋和太平洋是我們在地理课上学过的“四大洋”。而如今，我们又有了一个全新的大洋。

在 2021 年 6月8日举行的第十三届“世界海洋日”上，美国国家地理学会宣布承认南极洲的南大洋为地球第五大洋。

不同于北冰洋、大西洋、印度洋和太平洋，南大洋并不由周围的大陆划分，而是依据南极绕极流划分。据美国《国家地理》报道，南大洋包括了南纬 60 度以南的南极洲周围大部分水域。

“南大洋由强劲湍急的南极绕极流环绕，是唯一的与其他三大洋相接、完全包围一块大陆而非被大陆所包围的海洋。”美国海洋生物学家及海洋学家席薇亚·厄尔在接受《每日邮报》采访时表示。

熟悉南大洋的人都知道它与众不同。“任何去过南大洋的人都很难解释其迷人之处，但他们都会同意，与你能去的任何其他地方相比，那里的冰川更蓝，空气更冷，山川更令人生畏，风景更迷人。”美国国家海洋和大气管理局的海洋科学家赛斯·西克拉 - 博迪在接受美国《国家地理》采访时说道。

南大洋拥有独特的生态环境，因此成为数千种独特物种的栖息地。南大洋还拥有更广泛的生态影响。例如，据《每日邮报》报道，众所周知，座头鲸在夏季以南极附近的小虾为食，后向北迁移，到气候更温暖的中美洲和南美洲度过更寒冷的冬季。

美国《国家地理》希望修订地图能够增强公众对该地区的认知，从而鼓励对南大洋的保护——但其意义还不止于此。

“从教育以及地图注记的角度而言，我们认为让公众关注南大洋成为‘第五大洋这点非常重要。”美国国家地理学会的地理学家亚历克斯·泰特在接受《华盛顿邮报》采访时表示，“这样学生们学习海洋世界的部分时，会了解到这是一片相互连通的海洋，了解到这些被称为海洋的区域意义重大，了解到在南极洲周围的冰水中，还有一片独特的海洋。”