An overview of Atlantic forcing of the North Sea with focus on oceanography and biogeochemistry

This paper provides an overview of the current knowledge of Atlantic forcing of the North Sea's hydro- and biogeochemical dynamics. The North Atlantic Oscillation (NAO) causes the largest short-term variations via common large scale atmospheric variations and the wind-driven exchange of water masses. On longer time scales the zonal shifts in the position of the subpolar front (SPF) in the eastern North Atlantic, also triggered by the NAO, determine the oceanic settings in the northern and central North Sea. The hydrodynamics of the southern North Sea are influenced more by local forcings. The influence of Atlantic forcing extends to the biogeochemistry of the northern North Sea, but its influence on primary production is still unclear. Climate change is expected to reinforce some of the forcing mechanisms but may reduce others, and further work is advised to firm up the projections available to date.

Automated summary

This paper provides an overview of the Atlantic forcing on the hydro- and biogeochemical dynamics of the North Sea. The North Atlantic Oscillation (NAO) and zonal shifts in the position of the subpolar front (SPF) have significant impacts on the oceanic settings and biogeochemistry of the northern and central North Sea. Climate change is expected to reinforce some forcing mechanisms while potentially reducing others.