The Arctic Ocean Halocline Variability Over the Past 20 Years

The role of the ocean on the sea-ice mass balance in the Arctic is still a matter of hot debates. The study of the cold and shallow halocline is essential to understand the mechanisms leading to the formation and/or disappearance of arctic sea-ice. According to Steele and Boyd (1998), the cold halocline disappeared from the Eurasian basin during the early 90's due to a shift in the atmospheric wind forcing that would have changed the location where fresh Siberian shelf waters flow into the deep Arctic Ocean. Boyd (2002) and Bjork (2002) announced the recovery of the arctic halocline in the late 90's. Is this kind of event unique or does it occur more or less regularly? Does this kind of event influence the surface layer heat content and consequently the sea-ice mass balance? What is the current situation in the context of a highly variable arctic sea-ice cover during recent years? Based on a large data set collected in the central arctic basin during the 4th IPY and the Damocles project, the main goal of this poster will be to address these questions and to provide some answers.