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Abstract: This work proposes a new method to reconstruct and forecast surface Chlorophyll (Chl) from remotely sensed (SeaWiFS) data in the Alboran Sea, based on the correlation between zonal wind velocities and satellite Chl concentrations. First, the spatial and temporal variability of Chl and zonal wind have been characterized using standard statistics. Second, the annual cycle and trends are removed from the original time series and the residuals submitted to an EOF computation scheme. Then, the correlations between the amplitudes of the first temporal modes of Chl-wind couple have been quantified. Using the most highly correlated pair (Chl-zonal wind, with r=0.63), a simple linear relationship is proposed to reconstruct and forecast the Chl field. This forecasting method is more efficient than persistence for forecast horizons longer than 100days, with a mean correlation between original and predicted field of 0.73 as compared to 0.5 for persistence for all the year round. In partic\ular, this new method gives a 0.95 mean correlation for periods from 100 to 290days (while persistence gives 0.5). However, for a constant 8-days prediction horizon the persistence performs marginally better than the proposed method (0.79 vs. 0.68), giving some insight into the temporal scales of the features studied. These results may have significant implications for both short-term operational applications and seasonal forecasts. [Copyright &y& Elsevier]

Abstract: The sea level rise in the 1990s at the Mediterranean Sea as evidenced by satellite altimetry is studied with the aid of ocean models. Two barotropic two dimensional (2d) models and one three dimensional (3d) model are used. Both 2d models indicate that the contribution of direct atmospheric forcing causes localised trends of up to 2 mm/yr. The 3d model successfully describes the evolution in temperature of the upper and intermediate waters. However the salinity changes are not well described. The steric contribution of sea level rise during this period is in places in excess of 10 mm/yr. Notably oceanic circulation is also found to contribute to sea level trends by up to −3 mm/yr. Thus the observed sea level changes in the 1990s are better understood. The exceptional nature of the sea level behaviour in 1990s, especially in the eastern basin, when compared with previous decades is confirmed on the basis of both the 2d and the 3d models. [Copyright &y& Elsevier]