NORTH ATLANTIC OSCILLATION AND RAINFALL VARIABILITY ON THE SOUTHERN COAST OF THE MEDITERRANEAN

Regions of the south-western Mediterranean basin were the focus of many studies since they have experienced a series of climate changes. The contribution of the North Atlantic Oscillation in precipitations is required to be analyzed with the aim to understand the possible hydrological changes. In this way, an analysis of precipitations along the coast of central Maghreb (Morocco, Algeria and Tunisia) was carried. The present analysis was performed using (1) The graphical method of information processing and (2) wavelet transform technique. Results can be summarized as the following. Results show a high drought observed in all studied regions since the med-eighties and a return of the wet period since year 2003. Moreover, we demonstrate significant links of precipitations with the North Atlantic Oscillation