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Panthalassa, also known as the Panthalassic or Panthalassan Ocean, (from Greek Ïá¾¶Î½ all and Î¸Î¬Î»Î±ÏÏÎ± sea), was the superocean that surrounded the supercontinent Pangaea. During the PaleozoicâMesozoic transition c. 250 Ma it occupied almost 70% of Earth's surface.
Farther north, the Atlantic opens into the Arctic Ocean, which is connected to the Pacific by the Bering Strait: The Southern Ocean is the ocean surrounding Antarctica, generally the ocean south of sixty degrees south latitude. Parts of the Southern Ocean are covered in sea ice, the extent of which varies according to the season. The Southern Ocean is the second smallest of the five named oceans.