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Where is the boundary of the Southern Ocean usually placed?

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Map graphic showing the boundaries of the five oceans-Pacific, Atlantic, Indian, Arctic, and Southern-using color-coded regions. Four different map projections are included: North Pole view, South Pole view, International Date Line view, and Greenwich Meridian view, each displaying the oceans' extents around the continents. — ocean Earth's oceans and their marginal seas cover nearly 71 percent of the planet's surface.

The boundary of the Southern Ocean is most commonly defined as the waters surrounding Antarctica that lie south of 60° S latitude.123

While this latitudinal coordinate serves as a widely accepted limit, the region is also characterized by the Antarctic Convergence. This is a major boundary zone where cold, dense Antarctic surface waters meet and sink beneath warmer sub-Antarctic waters, creating a significant biological and hydrological transition.43