Integrated study of southern ocean biogeochemistry and climate interactions in the Anthropocene “BELCANTO III”. Final Report

The overall objective of the BELCANTO III project was to conduct targeted process studies and develop new proxies to construct and validate a realistic 3D ice-ocean biogeochemical model for the area south of latitude 30°S, based on improved understanding of the different factors regulating interactions between the atmosphere, ocean circulation and biogeochemical cycles and on synthesis/collection of existing/new data sets. The specific objectives were: - to improve our understanding about the iron cycling, with focus on the significance of iron-organic matter interactions for iron bioavailability and the efficiency of the biological pump (WP1) - to quantify nutrient consumption, CO2 uptake and C-export by assessing seasonality and interannuality of nutrient (Si, N) uptake; reconstruct carbon uptake and export from the surface layer via a multi-proxy approach; provide a relevant data set for 3D-NEMO-SWAMCO model validation (WP2) - to characterise the biogenic particles exported from the surface to the twilight zone and study their fate by quantifying remineralisation rates (WP3) - to model biogeochemical cycles in the modern Southern Ocean including seaice biogeochemistry (WP4) - to estimate impact of future climate change in the Southern Ocean through process-studies and modelling approaches (WP5).