The Barents Sea Opening (BSO) is an oceanographic term for the Western Barents Sea, the sea area between Bear Island in the south of Svalbard and the northern extremity of Norway through which a water mass of Atlantic origin flows into the Arctic Ocean. The inflow of relative warm water into the Arctic Ocean occurs not only through the Barents Sea Opening, but also through Fram Strait which is much deeper. The internal energy entering the colder waters has an influence on the atmosphere and the sea ice above and therefore possibly on the global climate.