Centro Euro-Mediterraneo per i Cambiamenti Climatic i,Bologna,Italy Istituto Nazionale di Geofisica e Vulcanologia, Bol ogna, Italy

Global ocean modelling activities at Centro Euro-Me diterraneo per i Cambiamenti Climatici (CMCC) include the development and implementation of data assimilation techniques appl ied to a global ocean general circulation model to investigate the role of the ocean on climate variability and predictability. T he main objective is the production of global ocean re-analyses over multidecadal periods to reconstruct the state of the ocean and t he large scale circulation over the recent past for climate applications and for the assessment of the benefits of assimilating ocea n observations on seasonal and longer climate predi ctability. Here we present the main characteristics of the ass imilation system and a set of global ocean re-analy ses produced with this system. Applications of these data assimilation pro ducts to the study of climate variability and to th e assessment of subsurface ocean initialization contribution to seasonal clima te predictability will also be reported.