The Chukchi Sea
The Chukchi Sea is a marginal sea of the Arctic Ocean, located between Chukotka and Alaska. In the West, the Long Strait connects with The East Siberian Sea, In the east near Cape Barrow connects with the Beaufort Sea, in the south Bering Strait connects it with Bering Sea Pacific Ocean. Through the water area of the sea passes the line of change dates.
A characteristic feature of the Black Sea is the complete (with the exception of a number of anaerobic bacteria) lack of life at depths greater than 150-200 m because of the saturation of deep layers of water with hydrogen sulfide.
The coastline is indented slightly. Gulfs: Kolyuchin Bay, Kotzebue, Shishmaryov Bay. The rivers flow into the Chukchi Sea a little, the largest - Amguema (river) and Noatak. On the mainland coast of the Russian part of the Chukchi Sea there are many lagoons. The largest of them are Kanygtokynmanky, Erkokynmanky, Tankergykynmanky and Nutevia.
In the Bering Strait area, the water temperature in summer rises to 12 ° C. As you move north, the temperature drops to negative values. In winter, the water temperature almost reaches the freezing point (-1,7 ° C). The water temperature decreases with depth, but in the eastern part of the sea in summer it remains positive to the very bottom. The water temperature on the surface in winter is 1,8 °, in the summer from 4 to 12 °.
Winter is characterized by high salinity (about 31-33 ‰) under the ice layer of water. In the summer, salinity is less, increases from west to east from 28 to 32. At melting edges of ice salinity is less, it is minimal at the mouths of rivers (3-5 ‰). Usually, the salinity increases with depth.
The Chukchi Sea is located on the shelf with depths of 40-60 meters. There are shoals with depths of up to 13 meters. The bottom is cut by two canyons: the Herald Canyon with a depth of up to 90 meters and the Barrow Canyon with a maximum depth of 160 meters (73 ° 50 'north 175 ° 25' W (G) (O)). The bottom of the sea is covered with loose mud with sand and gravel.Fauna
The animal world of Ch.M. is characterized by a mixture of the forms of the Arctic and Pacific oceans: whales, seals, seals, Walruses, White bears. From fish there are grayling, navaga, char, polar cod, etc. In summer, ducks, geese, seagulls and other sea birds abound on the shores and islands.
The hydrological regime of the Chukchi Sea is determined by the interaction of cold Arctic waters and the straits of the warmer waters of the Pacific Ocean entering the Bering Strait, severe climatic conditions, the arrival of floating ice from the north and west. The Alaskan current flows into the Chukchi Sea through the Bering Strait at a water speed of up to 2 meters per second, turning into the sea northward to the shores of Alaska. In the vicinity of the island of Lisborn from the Alaska Current, the western stream branches to Wrangel Island. In addition to Alaskan, there is a current that, through the Long Strait, comes from the East Siberian Sea and carries its cold waters along the shore of the Chukchi Peninsula. In summer anticyclonic circulation to the west is manifested, especially in the north of the sea, but storm winds strongly influence its character and strength. Strong wind in the autumn period contributes to the emergence of waves up to an altitude of 7 meters, in winter with the formation of the ice cover, the excitement weakens. In the summer, the excitement is less because of the decrease in storm activity. In the Chukchi Sea there are strong overtaking phenomena when, under the influence of storm winds, the sea level rises by 3 meters or more.
The tides in the sea are insignificant: the average magnitude of the tides is about 15 centimeters. Almost the whole year the sea is covered with ice. A warm Alaskan current leads to the cleansing of the southern part of the sea from the ice at 2-3 month in the warm period of the year. The cold current from the East Siberian Sea brings with it a lot of ice to the coast of Chukotka. The north of the sea is covered with perennial ice thicker than 2 meters.