Interannual Variability in the Mediterranean Sea: a Long-Term Monitoring Strategy

Recent studies have shown that the Mediterranean Sea is far from being in a steady state. Important and abrupt changes in the stratification and in the thermohaline circulation have occurred both in the eastern basin (during the 90s) in the western basin (since 2005). A continuous monitoring of the Mediterranean circulation is necessary to detect possible changes when they happen and to understand their time scales. Straits and channels form an important network inside the basin. Long-term monitoring of Mediterranean straits together with repeated observations in deep-basin sites of special interest demonstrated the capability to determine the evolution of the water mass characteristics and the transport variability at a basin scale. The on field activity developed during the last twenty years permitted to follow the interannual variability of Mediterranean water mass properties and circulation, while provided significant insight on the main involved processes.