Estuaries and Lagoons of the Russian Arctic Seas

Abstract

The seas of the Arctic (Barents Sea, White Sea, Kara Sea, Laptev Sea, East-Siberian Sea, Chukchi Sea) wash over Russian territory from the North. Almost 70 % of Russian territory falls within the Arctic Ocean basin. Despite the necessity of monitoring instances of natural and technogenic changes in the Arctic, many segments of the Arctic coast are still “blank spots” for researchers. The main reason for the poor knowledge in regard to this region is its inaccessibility. Its lagoons and estuaries are among the most difficult for the study of natural geosystems, each of them distinguished by both natural features and their response to changes in external conditions.

The variations of accumulative shores (lagoon, delta) are widely spread within the Barents and Laptev Seas. They form a great many lagoons. The biggest estuaries are the Kola Gulf, situated near the city of Murmansk, and the Khatanga and Anabar estuaries. There are not that many full scale lagoons along the coasts of the Kara Sea, a fact which is related to the geological structure of the shores, the peculiarities of which do not facilitate the development of accumulative bodies. But the largest estuaries of the Russia Arctic coast are the estuaries of the Kara Sea: Obskaya Guba, Taz Guba, Yenisey Gulf, Baidaratskaya Guba and Gydanska Guba. A characteristic peculiarity of the East Siberian Sea is a long extension of the accumulative coasts (about 40 %), especially on the islands. The accumulative-lagoon systems are distinguished for their peculiar internal partition into a number of round basins. Accumulative bay-bars separating the shallow lagoons from the Chukchi Sea extend parallel to the continental coast over hundreds of kilometers. The bay-bar of the Tenkergynpilgyn Lagoon is approximately 100 km long, and the length of the Kuvetpilchin Lagoon exceeds 50 km. The abundance of coastal accumulative structures and the lagoons that they form is a consequence of the geological structure of the adjacent coast and the topography of the submarine slope.

The major portion of the lagoons of the Russian Arctic coast is formed by accumulative bodies: bars, bay-bars, and spits. The influence of the changes in external conditions on the accumulative coastal bodies is different depending on their type of feeding and formation. Over recent decades, changes in all climatic parameters have been observed throughout the planet, especially in the Arctic regions. This natural global process inevitably influences the state of geosystems along the entire Arctic coast, including lagoons and estuaries. At present, it is impossible to say with certainty how large the positive or negative consequences of the Arctic’s climate changes will be. Human activities in the Arctic almost always have a negative impact upon the environment. Environmental protection measures may decrease this impact but are not capable of preventing it in full measure. Fortunately, the severe natural conditions do not allow for a large scale development of the coast, as has happened in more favorable regions.