Arctic ocean wildlife. Photo: Norwegian Polar Institute

In the Barents Sea, the general pattern of circulation is strongly influenced by large-scale atmospheric circulation, inflow of waters from adjacent seas, bottom topography, tides, and other factors — all of which make it rather complicated and variable (Figure 2.3.1).

Meteorological observation in Northern Barents Sea. Photo: Norwegian Polar Institute

Climate conditions in the Barents Sea are determined by both Atlantic and Arctic climate systems, and the winter North Atlantic Oscillation (NAO) explains about 15-20% of the inter-annual variability in air and sea temperatures in the southern region. The climate oscillates between warm and cold states. The warm state is characterized by low air pressure over the Sea giving southwesterly winds which cause increased Atlantic inflow, higher seasonal temperatures, and more northward positioning of the Polar Front.