Seasonal and interannual variability of the sea surface temperature structure in the Adriatic Sea

Seasonal and interannual variability of the sea surface temperature field in the Adriatic Sea is analysed using a five years time series of daily AVHRR (Advanced Very High Resolution Radiometer) data. The data used are the 9 km resolution sea surface temperature maps obtained in the framework of the Pathfinder project. This spatial resolution allowed analysis of only basin and sub-basin scale features. Average monthly sea surface temperature maps for the entire studied period (1987-1991) are discussed. The analysis shows the absence of any permanent surface feature in the Adriatic Sea. The cyclonic circulation of the south Adriatic Sea is marked by a surface temperature minimum that recurrently appears in late autumn or early winter, ie, in the preconditioning and deepwater formation phase. During autumn the surface inflow of Ionian water is observed while the Adriatic outflow is more evident in winter. Results of an EOF analysis suggest that the intensity of the western coastal cold water plume and the north Adriatic thermal front vary from year to year. Other subasin features like the south Adriatic gyre also display year-to-year variability.