Climate and oceanography of the Northern Hemisphere are controlled by thermohaline circulation of the World Ocean (Aagaard & Carmarck 1994; Broecker 1997). Important part of this circulation system is Gulfstrom, which transports warm and saline Atlantic waters to Norwegian Sea and further to the north where – as West Spitsbergen Current, reaches the Arctic Basin. The recent studies revealed that the atmospheric circulation pattern (exemplified by NAO Index) is closely related to the ocean currents (Morison et al. 1998; Planque & Taylor 1998; Dickson 1999).

In the European part of the Arctic the delivered water masses are cooled and after falling down into deeper parts of the ocean are transported southward again (Aagaard et al. 1985). Between the warmer Atlantic waters and cold, less saline Arctic waters develops a polar front, which is characterised by strong gradients in water temperature and salinity (Kostianoy et al. 2004). Changes in its position may reflect intensity of warm Atlantic waters northward flow – one of the most important climate controlling factor. Significant differences in water properties on both sides of the polar front cause that the bioproductivity and sedimentation conditions differ and changes in the front position may be recorded in marine sediments.

The next important effects of air temperature and precipitation fluctuations are variations in glacial processes. Increased influence of Atlantic air masses results in increase of temperature and precipitation and to a certain degree may intensify glacial processes (larger accumulation, bigger ice mass flux). The dry and cold Arctic air masses through enlarging of water retention period in glaciers, and the slower flow velocities of the glaciers tongues, restricts the glacial processes dynamics. So, the effects of changes in dominating circulation pattern may be recorded in the fluctuations of glaciers front positions as well as in amount of freshwater delivered due to ice ablation (Dowdeswell 1995; Dowdeswell et al. 1997). The changes associated with polar front fluctuations and glacial dynamics have important impact on biological processes in marine environment. The permanently ice covered Arctic Ocean belongs to the least productive regions in the world (Gosselin et al. 1997) so the decrease in sea ice cover (e.g. due to enlarged warm Atlantic waters transport) would cause increase in bioproductivity of this part of the ocean. On the other hand, glaciers retreat and associated increase in delivery of turbid meltwater to the sea (Svendsen et al. 2002; Zajaczkowski et al. 2004) will cause decrease in euphotic zone thickness and may limits the organic productivity.