Sea level in the Mediterranean Sea: The contribution of temperature and salinity changes

Abstract

The steric sea level variability in the Mediterranean Sea is estimated from the Medar climatology. Temperature variations cause most of the overall steric sea level change in the upper 400 m. Between 1960 and the 1990s cooling of the upper waters of the Eastern Mediterranean caused reduction in the steric heights while after 1993 warming caused sea level to rise. The steric sea level changes in the upper waters of the Adriatic and the Aegean Sea are correlated with the North Atlantic Oscillation. The comparison between the steric sea levels and coastal tide-gauges is unsatisfactory. This discrepancy questions both the practice of estimating basin-wide sea level changes on point measurements and the use of steric height variations as measures of sea level variability in areas less sampled than the Mediterranean. Moreover the diverse behaviour of the Eastern Mediterranean at sub-basin scales questions the meaningfulness of climatic basin averages.