Temporal linkages between the Faroe-Shetland time series and the Kola section time series

The Faroe-Shetland time series and the Kola time series cover a time period of more than hundred years and represent two of the longest oceanographic time series in the world. The relationship between these important time series is examined in this paper, which presents for the first time comparisons between the annual mean sea level and the temperature and salinity of Atlantic Water in the Faroe-Shetland Channel and the Kola section in the Barents Sea. The investigation is based on a wavelet spectrum analysis used to identify the dominant cycle periods and cycle phases in all time series. The identified cycles are compared to dominant cycles in sea level time series from Aberdeen and Hammerfest. The investigation has identified a correlation better than R=0.8 between dominant temperature cycles and the 18.6 year lunar nodal tide in most time series. The paper presents the correlations to the lunar nodal tide, the phase relationships between the dominant cycles and the signal to noise ratio between the dominant cycles and other unknown sources. The identified 18 year cycles seem to have a temporary stationary cycle time and a time variant phase. The dominant 18 year temperature and salinity time series in the Faroe-Shetland Channel and the Kola section had a phase-reversal that started in about 1920-25. A cycle phase-reversal may be explained by an amplitude modulation between the 18 year cycle and a more low frequent cycle.