In Green Edge, we focus on primary productivity and on the fate of organic matter produced by phytoplankton during the most productive period of the year: spring. Green Edge is also partly motivated by the recent discovery that phytoplankton blooms may occur more extensively and more often under the ice-pack. Green Edge will contribute to the major societal challenge of efficient resource management and adaptation to climate change, through a better understanding and anticipation of environmental change. We will address significant knowledge gaps in Arctic marine biogeochemical cycles and the food web, and their linkages with local human populations. Green Edge is a large multidisciplinary project that brings together concepts extending from oceanography to whole-ecosystems, to impact on society. Green Edge will significantly contribute to the new French Arctic Initiative, which is currently being implemented (www.chantier-arctique.fr).