This, the smallest of the four oceans, lies almost entirely above the Arctic Circle (66.5° N). Nearly surrounded by land, its only outlets are the Bering Strait between Alaska and Russia, Davis Strait between Greenland and Canada, and Denmark Strait and the Norwegian Sea between Greenland and Europe. The Arctic Ocean has an area of 14,090,000 sq km and an average depth of 3,658 m off of the continental shelf. The lowest point is Fram Basin which is 4,665 m deep. The Artic Ocean has the widest continental shelf of all the oceans.

The Arctic Ocean is divided into two basins, the Eurasian Basin, and the North American Basin, by the Lomonosov Ridge. There are also submarine ridges between the Arctic and Atlantic Oceans. This results in a large stagnant pool of cold water at the bottom of the Arctic Ocean, since land and submarine ridges block water from flowing out. The main current in the Arctic Ocean is the East Greenland current. This current is strong due to the number of rivers that flow into the Arctic Sea, the low rate of evaporation, and the land and submarine ridges surrounding the ocean. Two other weak currents flow out of the Arctic Ocean, the Labrador Current which runs through Smith Sound and Baffin Bay, and one that runs out of the Bering Straight. There is also a circular current in the Arctic Basin which is created by water deflecting off of Northern Greenland.

The central part of the ocean is permanently covered in about ten feet of ice. Pressure ridges in the ice can sometimes reach three times that height. In the summer months, the icepack is surrounded by water and free-floating. During the winter, the icepack expands to nearly twice its summer area, reaching the land on all sides. Due to the extreme temperatures people thought that non-oceanic life didn't exist in the Arctic. However, marine life abounds in the open seas, and hares, polar bears, seals, gulls, and guillemots have been found as far north as 88°.