Épisodes secs en hiver dans le bassin méditerranéen : variabilité et forçages atmosphériques (1957-2013).

The mean number of dry days in winter increased in the Mediterranean Basin during the 1957-2013 period,mainly because of dry spells becoming longer. The shortest events (Very Short Dry Spells) were less frequentwhereas longer events (Short Dry Spells, Medium Dry Spells and Long Dry Spells) were more frequent on theMediterranean Basin. 76 very long events (Very Long Dry Spells – VLDS) occurred during the 1957-2013period. A hierarchical clustering analysis of these VLDS events allows to detect 5 mainly Mediterraneanconfigurations: North-West Mediterranean, West Mediterranean, North-East Mediterranean, South-EastMediterranean and localized events.