1. Bogi Hansen & Hjálmar Hátún Faroe Marine Research Institute Iceland Scot- land Nordic Seas Faroes 0.8 Sv 3.8 Sv Greenland Østerhus et al., GRL 2005 The northern source of the Norwegian Atlantic Current NwAC Faroe Current Its forcingand bifurcation

2. The Faroe Current 4 CTD cruises a year along the standard section

3. Deploying trawl-protected ADCP

4. Recovering trawlprotected ADCP

5. Definition: Atlantic water is water that has recently crossed the Greenland- Scotland Ridge into the Nordic Seas and has not been mixed with ambient waters.

6. 3-point mixing model

7. Monthly and annually averaged Atlantic water transport in the Faroe Current 1997 - 2008 Average: 3.5 Sv

8. What is the force, driving the IF-inflow ? A stable transport requires a stable force Sea-level Wind

9. Correlation between monthly averaged Atlantic inflow and wind stress

10. Iceland Scot- land Faroes Transport Sea-level drop: SLHW - SLHE Monthly correlation: R = 0.63 Annual correlation: R = 0.87 Atlantic inflow and sea-level drop across the Ridge SLHW SLHE

11. Iceland Scot- land Faroes

12. Iceland-Faroe Atlantic inflow Atlantic Ocean Nordic Seas Atlantic inflow Iceland Faroe Ridge IFR-overflow FBC-overflow To Arctic Ocean To Denmark Str. Sea-level drop Remote wind forcing could raise sea-level west of Ridge R > 0 R < 0 West East Outflow from Nordic Seas could lower sea-level east of Ridge 8.5 Sv out implies lowering of Nordic Seas SLH by 30 cm/day

13. Correlation coefficient between monthly sea-level height and Faroe Current inflow + _

14. Why are the exchanges that stable ? It takes decades to empty ”dam” Greenland Scotland Ridge World OceanNordic Seas Cooling Overflow AMOC

15. Monthly averaged overflow transport through the Faroe Bank Channel (Hansen & Østerhus, 2007) Millions of m 3 per second

16. Bifurcation of Faroe Current Helland-Hansen & Nansen, 1909 Salinity at 100 m depth in May 1904

17. PVDs from moored ADCPs (Hátún thesis, 2004) Red sticks: Surface Southern Faroe Current

18. Two ADCP records Explains 70% of variance EB NB

19. Seasonal transport variation from combined altimetry and geostrophy Seasonal amplitude: 0.6 Sv Maximum in March Seasonal amplitude: 0.2 Sv

20. Windstress and bifurcation Nordic Seas wind stress curl Sea-level tilt across the Southern Faroe Current Annual sea-level tilt