Over the past decade it became evident that the Arctic is undergoing significant and sweeping changes like increased air temperatures and enhanced wind mixing over most of the arctic shelf seas, reduced sea-ice cover and marked changes in amplitude and seasonality of river discharge. Most of these changes are already manifested on shelf environments. The Laptev Sea shelf (Siberian Arctic) and the Laptev Sea polynya were internationally defined as key regions in order to monitor and investigate variability and changes in system parameters in terms of changing boundary conditions as a result of climate change. Therefore the project focuses on oceanic frontal zones and polynya systems in the Laptev Sea by means of a multi-disciplinary approach including remote sensing, multi-year sea-floor observatories, ice camps and ship expeditions, and coupled sea-ice-ocean modelling. Russian-German research teams from Saint Petersburg, Moscow, Tiksi, Bremerhaven, Trier and Kiel will study the flaw polynya in response to oceanic, sea-ice and atmosheric forcings as well as feedbacks of the Laptev Sea flaw polynya to the Arctic System (sea-ice & brine-enriched water formation).