Objetivo We currently witness in the Arctic: 1) a decrease in summer ice cover that exposes sea surface to solar radiation and physical forcings, 2) permafrost thawing and increased river runoff, both leading to an increase in the export to ocean of organic carbon previously sequestered in the Tundra, and 3) an increase in ultraviolet radiation. These three phenomena potentially favour a growing mineralization of organic carbon through photo-oxidation taking place in the surface layer of the ice-free Arctic Ocean waters, resulting in an acceleration of the increase in atmospheric CO2. At the same time, the exposure of a larger fraction of ocean surface to sun light and the possible increase in nutrients brought by rivers lead to larger autotrophic production and sequestration of organic carbon. The general objective is to determine the absolute significance of organic matter photo-oxidation and of primary production, and their relative balance in the Arctic Ocean. Diagnostic (Part 1) and prognostic (Part 2) approaches will be developed to address the problem quantitatively. Part 1: Based on existing and new data collected in situ in different regions of the Arctic Ocean, we will developed 1) a model for light propagation through atmosphere and within ocean, 2) diagnostic models for the two light-related processes of interest, and 3) algorithms for the processing of ocean colour remote sensing data specifically in the Arctic Ocean. Organic matter photo-oxidation and primary production will then be estimated using different sources of remote sensing information (UV, clouds, ice, optical properties of surface waters) at various space and time scales. Part 2: The diagnostic models will be integrated into a coupled physical-biological ecosystem model including bacterial activity, and applied using Global Climate Model outputs to assess the fate of the associated carbon fluxes in the Arctic Ocean during the next decades under different climate change scenarios. Ámbito científico engineering and technologymaterials engineeringcolorsnatural sciencesearth and related environmental sciencesatmospheric sciencesmeteorologysolar radiationengineering and technologyenvironmental engineeringremote sensingnatural sciencesbiological sciencesecologyecosystemsnatural sciencesearth and related environmental sciencesatmospheric sciencesclimatologyclimatic changes Palabras clave Biogeochemistry (Climate change) Biological Biological oceanography Marine ecosystems and processes Programa(s) FP7-PEOPLE - Specific programme "People" implementing the Seventh Framework Programme of the European Community for research, technological development and demonstration activities (2007 to 2013) Tema(s) PEOPLE-2007-4-1.IOF - Marie Curie Action: "International Outgoing Fellowships for Career Development" Convocatoria de propuestas FP7-PEOPLE-2007-4-1-IOF Consulte otros proyectos de esta convocatoria Régimen de financiación MC-IOF - International Outgoing Fellowships (IOF) Coordinador CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS Aportación de la UE € 183 234,14 Dirección RUE MICHEL ANGE 3 75794 Paris Francia Ver en el mapa Región Ile-de-France Ile-de-France Paris Tipo de actividad Research Organisations Contacto administrativo Hélène Faradji (Dr.) Enlaces Contactar con la organización Opens in new window Sitio web Opens in new window Coste total Sin datos