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3. Natural Conditions in the NSR

 

3.1 Natural Conditions in the Arctic

The natural conditions prevailing in the NSR are utterly different from those anywhere else in the world where commercial shipping is conducted, with the possible exceptions of the Bay of Bothnia, the Gulf of St. Lawrence and the Great Lakes. Accordingly, ship design and construction, observation of ice conditions, navigation support systems and navigation plans must always carefully reflect the natural conditions both at sea and on land. Needless to say, the Arctic is also vitally important in terms of the earth's environment; any human activity in the region, including navigation, must presume a careful understanding of the nature of the Arctic, meticulous environmental impact assessment, and a comprehensive response to that assessment.

 

3.1.1 Physiography of the Arctic Ocean

The Arctic Ocean consists of a deep ocean basin, submarine ridges, continental shelves, and marginal plateaus. Five major epicontinental seas, the Barents, Kara, Laptev, East Siberian, and Chukchi seas, are located on the broad European and Siberian continental shelves. The Arctic Ocean is a sea with an area of 14 million square kilometers surrounded by the continents of Eurasia and North America and the vast island of Greenland. The Scandinavian Peninsula is separated from Greenland by a distance of 1,400km, which contains a deep abyssal plain 3,500m deep. The eastern end of this part of the Arctic Ocean, which abuts the North Atlantic Ocean, is called the Sea of Norway, while its western end is known as the Sea of Greenland. The Arctic Ocean opens to the North Pacific Ocean through the narrow passage of the Bering Strait, an 80km gap between the continents of Eurasia and North America. The Bering Strait is extremely shallow, being no deeper than 60m at its deepest point. The strait between Greenland and Ellesmere Island in Canada's Arctic Archipelago is roughly 20km wide and extends to a depth of 500m. This body of water leads through Baffin Bay and Davis Strait to the North Atlantic Ocean.

In the center of the Arctic Ocean, a deep abyssal plain stretches out 4,000m below the surface of the ocean, with its deepest point extending 5,440m below sea level. The seabed that extends from the northern tip of Greenland across the North Pole to the Novosibirskiye Ostrova (Islands) of Russia features a ridge called the Romonosov Ridge, which divides the Alaska side of the ocean from the European side. Other ridges lie roughly parallel on either side of the Romonosov Ridge. The ridge on the Northern European side of the Romonosov Ridge is called the Arctic Mid-oceanic Ridge (or Nansen-Gakkel Ridge), and the ridge on the Canadian side is named the Alpha Ridge. Approximately 70% of the Arctic Ocean is over 1,000m deep; the remaining 30% consists of a broad continental shelf. The European-Siberian continental shelf extends far into the Arctic, while the North American continental shelf is much narrower. The Beaufort and Lincoln Seas include areas over 1,000m deep.

 

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The Arctic Ocean

 

 

 

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