The Beaufort Sea is a marginal sea

Marginal sea

The term marginal sea has differing meanings. In one sense the term is equivalent to territorial waters. In another sense the term indicates a partially enclosed sea adjacent to or widely open to the open ocean, but bounded by submarine ridges...

 of the Arctic Ocean

Arctic Ocean

The Arctic Ocean, located in the Northern Hemisphere and mostly in the Arctic north polar region, is the smallest and shallowest of the world's five major oceanic divisions...

, located north of the Northwest Territories

Northwest Territories

The Northwest Territories is a federal territory of Canada.Located in northern Canada, the territory borders Canada's two other territories, Yukon to the west and Nunavut to the east, and three provinces: British Columbia to the southwest, and Alberta and Saskatchewan to the south...

, the Yukon

Yukon

Yukon is the westernmost and smallest of Canada's three federal territories. It was named after the Yukon River. The word Yukon means "Great River" in Gwich’in....

, and Alaska

Alaska

Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...

, west of Canada's Arctic islands

Canadian Arctic Archipelago

The Canadian Arctic Archipelago, also known as the Arctic Archipelago, is a Canadian archipelago north of the Canadian mainland in the Arctic...

. The sea is named after hydrographer

Hydrography

Hydrography is the measurement of the depths, the tides and currents of a body of water and establishment of the sea, river or lake bed topography and morphology. Normally and historically for the purpose of charting a body of water for the safe navigation of shipping...

 Sir Francis Beaufort

Francis Beaufort

Rear-Admiral Sir Francis Beaufort, FRS, FRGS was an Irish hydrographer and officer in Britain's Royal Navy...

. The major Mackenzie River

Mackenzie River

The Mackenzie River is the largest river system in Canada. It flows through a vast, isolated region of forest and tundra entirely within the country's Northwest Territories, although its many tributaries reach into four other Canadian provinces and territories...

 empties into the Canadian part of the sea, west of Tuktoyaktuk, which is one of the few permanent settlements on the sea shores.

The sea, characterized by severe climate, is frozen over most of the year; only a narrow pass up to 100 km (62.1 mi) opens in August–September near its shores.