Sector Zero

The Arctic is a future Biome. It will be added in a separate game mode in the upcoming Expansion Pack. In which it may make up the entire playable area.

The Arctic landmass can be seen in the ending scene of Subnautica, as the Neptune Escape Rocket orbits Planet 4546B.

No Concept Art of the Arctic Biome has been revealed, but it can be assumed that it would consist of several large ice caps which can be explored both above and below.