Using data from 1910 to 1997, we study the mean structure as well as the interannual variability in the autumn hydrography of the part of the West Spitsbergen Current (WSC) confined over the upper continental slope and of its continuation, the Svalbard branch. This is known to provide a major pathway for warm and saline Atlantic water to the Arctic Ocean. We focus our study on the area northwest of Svalbard, around 80 degreesN. The time series of subsurface hydrography (100-300 m layer) show interannual variations which are, in the 1980s and 1990s, quite coherent with hydrographic time series obtained upstream in the WSC around 76 degreesN as well as with variations in the large-scale atmospheric patterns, as indicated by the North Atlantic Oscillation (NAO) index. However, in the 1970s, the coherence is poorer. Our results suggest that it may be important to focus on the narrow domain of the part of the WSC confined over the upper continental slope in order to get consistent estimates of the Arctic Ocean inflow signal in the Fram Strait, The warming in this inflow signal (in 1970-1996) does not seem to have been as strong as previously suggested. [References: 44]
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