PELAGIC-BENTHIC COUPLING IN THE NORDIC SEAS - THE ROLE OF EPISODIC EVENTS

The consequences of the following episodic phenomena for the pelagic-b enthic coupling in the Nordic Seas are illustrated: (I) Advection of w ater masses between fjords and shelf environments, (2) freshwater run- off and vertical stability, (3) dynamics of the marginal ice zone in t he central and northern Barents Sea and the Polar Ocean, (4) drift pat terns of sinking particles along the North Norwegian coast, (5) advect ion of zooplankton into subarctic fjords and the southern Barents Sea, zooplankton overwintering and composition, and (6) transport of organ ic particulate matter from the Barents Sea shelf. It is shown that phy sical processes in the north-eastern North Atlantic and Polar Ocean ca n be strongly variable on time scales of days to decades. They have a significant influence on the dynamics of pelagic-benthic coupling. The physical oceanography influences the vertical and horizontal particle flux not only directly (mixing, advection, up- and down-welling), but also indirectly through its impact on the biota (for example radiatio n, wind, ice cover, freshwater run-off and overwintering, advection an d retention of zooplankton). Understanding pelagic-benthic coupling at high latitudes depends even more on a best possible understanding of the physical oceanography and the time scales involved than elsewhere.