At high latitudes the sea ice cover affects the interaction processes between atmosphere and ocean, mainly due to its isolating effect on the vertical heat transfer and the horizontal transport of latent heat and freshwater.
The temporal behavior of the Arctic sea ice cover is investigated with a dynamic-thermodynamic sea ice model. The model is integrated for 40 years with a daily time step.
Daily fields of wind and air temperature for the period 1958-1997 derived from the NCEP/NCAR reanalysis project are used as atmospheric surface forcing. The simulation results of the model (e.g. sea ice transport, sea ice extent) at a horizontal resolution of 1 by 1 degree show high variability at all time scales. Spectral analysis of the time series of sea ice export into the Greenland/Iceland/Norwegian (GIN) Seas reveals that most of the variance is apparent at periods of 6-7 years and that there is also enhanced variance at the decadal time scale (12-14 years). The highest sea ice export into the GIN Seas occured in 1968 and was, as a consequence of the anomalous direction of the Transpolar Drift Stream, associated with the maximum sea ice extent in the GIN Seas within the entire simulation period.
On the western side of Greenland, the sea ice export through Davis Strait shows large variability on the decadal time scale. An expansion of the model domain further southward in order to fully include the Labrador Sea and an enhancement of the horizontal resolution (to 0.5 by 0.5 degree) will enable the investigation of sea ice extent variations as response to atmospheric forcing in the western North Atlantic region