Laptev sea

The Laptev Sea is a marginal sea of ​​the Arctic Ocean. It is located between the Taimyr Peninsula and the Northern Earth Islands in the west and the Novosibirsk islands in the east. The sea is named in honor of the Russian polar explorers of the cousins ​​Dmitri and Khariton Laptev (originally the sea bore the name of Nordenskiöld).

The banks are very rugged. Large bays: Khatangsky, Olenek, Faddeia, Yansk, Anabar, Maria Pronchishcheva Bay, Buor-Khaya. In the western part of the sea there are many islands, mostly off the coast. In the south-western part of the sea there are islands of Komsomolskaya Pravda. The rivers flow into the sea: Khatanga, Anabar, Olenyok, Lena, Yana. Some rivers form large deltas. The main port is Tiksi.

The bottom of the Laptev Sea - a shallow continental shelf, abruptly breaks to the bed of the ocean. The southern part of the sea is shallow, with depths of 20-50 meters. In the shallow-water areas, the bottom is covered with sand and mud with impurities of pebbles and boulders. Near river banks, river sediments accumulate at high speed, up to 20-25 centimeters per year. The continental slope is cut by the Sadko trough, which passes in the north to the basin of Nansen with depths over 2 kilometers, here the maximum depth of the Laptev Sea is marked - 3385 meters. At great depths the bottom is covered with silt.

The water temperature in the sea is low. In winter, under the ice, the water temperature is -0,8 ... -1,8 ° C. Above a depth of 100 meters, the entire water layer has negative temperatures (up to -1,8 ° C). In summer, in the ice-free areas of the sea, the uppermost layer of water can be heated to 4-6 ° C, in the bays to 10 ° C. In the deep sea zone at a depth of 250-300 meters are coming from the Arctic waters of the Atlantic relatively warm waters (up to 1,5 ° C). Below this layer, the water temperature again becomes negative to the very bottom, where the temperature is about -0,8 ° C.

Salinity of sea water at the surface in the northwestern part of the sea is 28 per mil, in the southern part - up to 15 per millet, near the mouths of rivers - less than 10 per mil. A strong influence on the salinity of surface waters is exerted by the flow of Siberian rivers and the melting of ice. With increasing depth, the salinity rapidly increases, reaching 33 per mille.

The surface currents of the sea form a cyclonic (i.e., counterclockwise) circulation. The tides are semidiurnal, with an average height of up to 50 centimeters. The magnitude of the tides greatly reduces the ice cover. The sea level surges are significant - up to 2 meters, and in the bays reach 2,5 meters. The Laptev Sea is one of the harshest arctic seas, the frosty winters cause a significant development of sea ice, which covers the water area of ​​the sea almost all year. The development of ice is also facilitated by the shallow water of the sea and the low salinity of its surface waters. For hundreds of kilometers from the coast deep into the sea, landfast ice with thickness up to 2 and more meters is widespread. Floating ice is observed in areas not occupied by fast ice, and icebergs are found on the northwestern edge of the sea.