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 NordicSeas and the Arctic Ocean is investigated using numerical hindcast and sensitivity experiments. Theocean-sea ice model reproduces observed propagation pathways and speeds of SST anomalies.Part of the signal reaching the entrance to the Nordic Seas between Iceland and Scotland originatesin the lower latitude North Atlantic. Response experiments with different prescribed conditionsat 50N show that changes in the barotropic flow across 50N have no impact on theseas north of the Greenland-Scotland Ridge because of the strong deformation of the f/H field.A temperature anomaly inserted in the upper 500m at 50N, on the other hand, has a widespread effect on the temperature distribution and the circulation in the high-latitude NorthAtlantic. NAC induced variability in the Nordic Seas and locally induced variabilityhave similar magnitude. The local atmospheric influence andthe complexity of North Atlantic - Nordic Seas advection pathways make it unlikely that detectionof signal propagation in the NAC could lead to a prediction of oceanic conditions inthe Nordic Seas and the Arctic Ocean with several years lead time.