Қара теңізі: Сибірдің солтүстігіндегі Арктикалық мұхитының шеткі теңізі

Marginal sea of the Arctic Ocean north of Siberia between Novaya Zemlya and Severnaya Zemlya

The Kara Sea is a marginal sea, separated from the Barents Sea to the west by the Kara Strait and Novaya Zemlya, and from the Laptev Sea to the east by the Severnaya Zemlya archipelago. Ultimately the Kara, Barents and Laptev Seas are all extensions of the Arctic Ocean north of Siberia. The Kara Sea's northern limit is marked geographically by a line running from Cape Kohlsaat in Graham Bell Island, Franz Josef Land, to Cape Molotov (Arctic Cape), the northernmost point of Komsomolets Island in Severnaya Zemlya. The Kara Sea is roughly long and wide with an area of around and a mean depth of
Its main ports are Novy Port and Dikson and it is important as a fishing ground although the sea is ice bound for all but two months of the year. The Kara Sea contains the East Prinovozemelsky field (an extension of the West Siberian Oil Basin), containing significant undeveloped petroleum and natural gas. In 2014, US government sanctions resulted in Exxon having until September 26 to discontinue its operations in the Kara Sea.

It is named after the Kara river (flowing into Baydaratskaya Bay), which is now relatively insignificant but which played an important role in the Russian conquest of northern Siberia. The Kara river name is derived from a Nenets word meaning 'hummocked ice'.

There are many islands and island groups in the Kara Sea. Unlike the other marginal seas of the Arctic, where most islands lie along the coasts, in the Kara Sea many islands, like the Arkticheskiy Institut Islands, the Izvesti Tsik Islands, the Kirov Islands, Uedineniya or Lonely Island, Wiese Island, and Voronina Island are located in the open sea of its central regions. The largest group in the Kara Sea is by far the Nordenskiöld Archipelago, with five large subgroups and over ninety islands. Other important islands in the Kara Sea are Bely Island, Dikson Island, Taymyr Island, the Kamennyye Islands and Oleni Island. Despite the high latitude, all islands are unglaciated except for Ushakov Island at the extreme northern limit of the Kara Sea.

Water circulation patterns in the Kara Sea are complex. The Kara Sea tends to be sea ice covered between September and May, and between May and August heavily influenced by freshwater run off (roughly 1200 km3 yr−1) from the Russian rivers (e. g., Ob, Yenisei, Pyasina, Pur, and Taz). The Kara Sea is also affected by the water inflow from the Barents Sea, which brings 0.6 Sv in August and 2.6 Sv in December. The advected water originates from the Atlantic, but it was cooled and mixed with freshwater in the Barents Sea before it reaches the Kara Sea.

There is concern about radioactive contamination from nuclear waste the former Soviet Union dumped in the sea and the effect this will have on the marine environment. According to an official "White Paper" report compiled and released by the Russian government in March 1993, the Soviet Union dumped six nuclear submarine reactors and ten nuclear reactors into the Kara Sea between 1965 and 1988. Solid high and low level wastes unloaded from Northern Fleet nuclear submarines during reactor refuelings were dumped in the Kara Sea, mainly in the shallow fjords of Novaya Zemlya, where the depths of the dumping sites range from 12 to 135 meters, and in the Novaya Zemlya Trough at depths of up to 380 meters. Liquid low level wastes were released in the open Barents and Kara Seas. A subsequent appraisal by the International Atomic Energy Agency showed that releases are low and localized from the 16 naval reactors (reported by the IAEA as having come from seven submarines and the icebreaker Lenin) which were dumped at five sites in the Kara Sea. Most of the dumped reactors had suffered an accident. The Soviet submarine K 27 was scuttled in Stepovogo Bay with its two reactors filled with spent nuclear fuel. At a seminar in February 2012 it was revealed that the reactors on board the submarine could re achieve criticality and explode (a buildup of heat leading to a steam explosion vs. nuclear). The catalogue of waste dumped at sea by the Soviets, according to documents seen by Bellona, includes some 17,000 containers of radioactive waste, 19 ships containing radioactive waste, 14 nuclear reactors, including five that still contain spent nuclear fuel; 735 other pieces of radioactively contaminated heavy machinery, and the K 27 nuclear submarine with its two reactors loaded with nuclear fuel.

The Great Arctic State Nature Reserve—the largest nature reserve of Russia—was founded on May 11, 1993, by Resolution No. 431 of the Government of the Russian Federation (RF). The Kara Sea Islands section (4,000 km2) of the Great Arctic Nature Reserve includes: the Sergei Kirov Archipelago, the Voronina Island, the Izvestiy TSIK Islands, the Arctic Institute Islands, the Svordrup Island, Uedineniya (Ensomheden) and a number of smaller islands. This section represents rather fully the natural and biological diversity of Arctic sea islands of the eastern part of the Kara Sea. Nearby, the Franz Josef Land and Severny Island in northern Novaya Zemlya are also registered as a sanctuary, the Russian Arctic National Park.