The Arctic is tricky to define, but here is a working definition:

Geographically: The Arctic Ocean and sub-Arctic seas; terrestially, the tundra and permafrost; and the atmosphere north of the region of the Polar Front.

Oceans: to be included in the definition, as well as the Arctic Ocean, are: Sea of Okhotsk and Bering Sea on the Pacific side; on the Atlantic side: the Barents Sea, the Nordic Seas (Greenland, Iceland and Norwegian Seas), Labrador Sea, Baffin Bay, Hudson Bay, the Irminger Basin (of the northern North Atlantic, as a direct recipient of surface and deep polar outflows) and the Baltic (a major freshwater input to the Arctic, via the Norwegian Coastal Current); and within the Arctic, the Siberian shelf seas (Kara, Laptev, East Siberian, Chukchi Seas) are assumed part of the Arctic Ocean. These seas all receive polar ice / water directly, and/or experience sea ice formation.

Land: permafrost and tundra means north of the northern tree-line. Permafrost is permanently frozen ground. Tundra is permanently frozen sub-soil. Tundra can have seasonally or continually thawed topsoil.

Atmosphere: north of the polar front covers the Arctic atmosphere, but "region of" allows inclusion of storm tracks and the polar jet as well as the polar cell.

Cryosphere: all Arctic sea ice, including land-fast ice; the terrestrial ice sheets, meaning the largest - Greenland - and all of the smaller ice caps; and their liquid (meltwater) and solid (iceberg) discharges.

The head of the NOCS Arctic Research Theme is Sheldon Bacon.