Impact of North Atlantic Current changes on the Nordic Seas and the Arctic Ocean

The impact of North Atlantic Current (NAC) volume, heat, and salt transport variability onto the Nordic Seas and the Arctic Ocean is investigated using numerical hindcast and sensitivity experiments. The ocean‐sea ice model reproduces observed propagation pathways and speeds of SST anomalies. Signals reaching the entrance to the Nordic Seas between Iceland and Scotland originate partly in the lower‐latitude North Atlantic. Response experiments with different prescribed conditions at 50°N show that changes in the barotropic flow across 50°N have no impact on the seas north of the Greenland‐Scotland Ridge because of the strong deformation of the f/H field. A temperature anomaly inserted in the upper 500 m at 50°N, on the other hand, has a widespread effect on the temperature distribution and the circulation in the high‐latitude North Atlantic. NAC induced variability in the Nordic Seas and locally induced variability have similar magnitude. The local atmospheric influence and the complexity of North Atlantic‐Nordic Seas advection pathways make it unlikely that detection of signal propagation in the NAC could lead to a prediction of oceanic conditions in the Nordic Seas and the Arctic Ocean with several years lead time.