Salinity variability in the German Bight in relation to climate variability

Abstract

A relationship between observed variability in large-scale climate and salinity in the German Bight is sought using a multivariate statistical approach. It is found that on an annual timescale, 90% of the observed salinity variability is in-phase and correlated with a lag of several months to large-scale air pressure. The statistical model is used to estimate annual salinity anomalies from large-scale air pressure back to 1900. The correlations between estimated and observed salinities range from r=0.4 to r=0.7, depending on the position. It is shown that advective precipitation is the mechanism that links air pressure and salinity anomalies. Advection of Atlantic Water has only a minor impact on the annula mean in the examined coastal zone. If air pressure data from a climate change experiment is used as predictor, a slight drop of the mean salinity level in the range of 0.2 to 0.3 psu is predicted for the near future.