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3.3.7 Ocean Currents and Tides

Ocean currents in the shallow continental shelf of the NSR, though governed by local geographical features, in general flow from west to east. In the narrow straits between islands the action of the tides becomes ferocious, as seafarers in the age of explorers frequently discovered.

Some of the fastest tidal flows are observed at Yugorskiy Shar Strait on the south coast of Vaygach Island, which lies between the Eurasian continent and Novaya Zemlya. When the northeast wind is strong, boosting the tidal force with wind power, the tides can reach a top speed of 6.9 knots. Close to the Vilkitskiy Strait south of Severnaya Zemlya, tides are clocked at about 5 knots; speeds of 3-4 knots are seen in the Dmitri Laptev Sea to the south of the Novosibirskiye Islands. Records of early voyages reveal that small ships were unable to pass through these treacherous straits, and had to wait until the tide turned.

Each tidal cycle is completed in half a day (12 hours). At ports constructed near the mouths of major rivers or in areas unaffected by current, the coastal geography factors strongly in the variation between high and low tide. In seasons when the river flow is high, large tidal effects can be expected. The design, construction and utilization of port and its facilities in the NSR should take these effects into account.

A detailed analysis of the tidal effects revealed that tidal effects were stronger along the NSR coast than in the center of the Arctic Ocean, by about 2 knots. With ocean currents, tides and winds amplifying each other and canceling each other out, fluctuations in direction and speed of flow are drastic, particularly in narrow straits.

 

GUIDE TO NAVIGATING THROUGH THE NORTHERN SEA ROUTE (No. 4151B)

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Distribution of maximum current speeds in the NSR (Administration of the NSR, 1996)

 

3.3.8 Marine Life

Moving northward to the Arctic coast, the flora and fauna of the taiga give way to forms of life that are better adapted to the harsher natural environment of the taiga. Unforgiving as the conditions in this realm may be, the vast continental shelf of the NSR is teeming with a stupendous variety of marine life. When the sun appears on the horizon to end the long Arctic night, phytoplankton, the base of the Arctic food chain, begin to bloom.

 

 

 

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