Southern Ocean

American  

[suhth-ern oh-shuhn] / ˈsʌð ərn ˈoʊ ʃən /

noun

1. the waters surrounding Antarctica, comprising the southernmost waters of the World Ocean, with its deepest section in the South Sandwich Trench. 8,478,800 square miles (21,960,000 square kilometers).

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Southern Ocean British  

noun

1. another name for the Antarctic Ocean

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Etymology

Origin of Southern Ocean

First recorded in 1660–70, referring to any southern sea; current sense dates from 1700–10

Example Sentences

"Normally, an increased supply of iron in the Southern Ocean would stimulate algae growth, which increases the oceanic uptake of carbon dioxide," says lead author Torben Struve of the University of Oldenburg.

From Science Daily • Feb. 4, 2026

"These results show that iron delivered by icebergs can be far less bioavailable than previously assumed, fundamentally altering how we think about carbon uptake in the Southern Ocean."

From Science Daily • Feb. 4, 2026

She traveled aboard a British research vessel across the South Atlantic Ocean and the Southern Ocean, moving from the South African coast to the edge of the Weddell Gyre's ice zone and back.

From Science Daily • Jan. 12, 2026

One was a former merchant marine whose wooden 32-foot ketch was barely adequate for a journey through the punishing Southern Ocean.

From The Wall Street Journal • Dec. 5, 2025

The cold air masses created by this icecap clash with the warm winds from the ocean to churn up a storm belt that surrounds the continent, making the Southern Ocean the most treacherous sea anywhere.

From "Shipwreck at the Bottom of the World" by Jennifer Armstrong