Variability in the Atlantic layer of the Arctic Ocean

Interannual variability dominates the Arctic ocean and atmosphere. The variability of the Arctic climate has been previously investigated using sea level pressure, the sea ice anomoly, wind patterns, and a combination of these. To see how much of this variability is related to the Arctic Ocean, we performed an empirical orthogonal function analysis of the depth to the zero degree isotherm (the upper limit of Atlantic layer) of the Arctic Ocean. We also composited the 0°C depth data using the AO index and the Arctic vorticity index so that we can see the 0°C depth difference between high indices years and low indices years and compare them with the EOF result. The AO composited pattern agrees well with the combined first two modes of the EOF and the vorticity composite agrees with the third EOF mode. This suggests that the Atlantic inflow to the Arctic and it's distribution are strongly related to the atmospheric variability over the Arctic.