The effect of wind-stress over the Eastern Mediterranean on deep-water formation in the Adriatic Sea

We investigate the effect of interannual variability of the wind-stress over the Eastern Mediterranean on Adriatic Deep Water (ADW) formation using an oceanic general circulation model of the Mediterranean Sea driven by monthly ERA-Interim wind-stress of the years 1979-2014. This is done by using climatological annual cycle of the surface temperature and freshwater flux but interannually varying wind-stress. A connection between the wind-stress magnitude over the Rhodes Gyre region and ADW outflow is found in association with the formation of Levantine Intermediate Water (LIW). 720 years artificially generated wind stress fields were constructed based on the first 50 Empirical Orthogonal Functions (EOFs) of the wind-stress monthly anomalies. This simulation strengthen the connection that was found and also reveal a centennial internal variability of both the LIW and the ADW outflow. It is also found that the intensity of the Rhodes Gyre is almost linearly related to the wind-stress amplitude. However, the ADW outflow is non-monotonically related to the wind-stress amplitude. There is an optimal wind stress amplitude for which the ADW formation is maximal. When the wind-stress amplitude is more than 50% the climatological mean wind-stress amplitude, the ADW outflow is weakened. This implies a different balance between the saline LIW and the fresh Atlantic Water, entering the Eastern Mediterranean from Sicily Strait, under stronger than present wind-stress amplitude.