“BARKALAV 2007–2009” – a complex expedition in the Barents, Kara, Laptev, and East Siberian Seas. The research was done within a framework of the national purpose-oriented research subprogram “Sea research in the Arctic, in the Russian seas, continental shelf and the World Ocean. Models and technologies of marine forecasts and calculations” as well as the scientific program of Russia’s participation in the “International Polar Year 2007–2008” program realization. The expedition was conducted at the expense of the federal budget. The research was aimed at obtaining new complex data on the contemporary state of the seawaters, studying seasonal cyclic characteristics of the environment in order to gain a better understanding of the climatic changes in ice, hydrological and hydrochemical regimes of the Arctic seas, as well as biological conditions and processes of sediment accumulation on the sea bed. The work within the program “BARKALAV-2008” in the White Sea, southeastern part of the Barents, Kara, East Siberian, and Laptev Seas, was conducted by the expedition of the Arctic and Antarctic Research Institute in the period of 3 months. The expedition in the Laptev Sea attracted scientists from Germany (GEOMAR Institute), who used their program of bottom station installation.