Identification of key processes/species and analysis of key rates of physical, biogeochemical and biological ecosystem components

This theme targets those state variables and rates that are either poorly constrained or insufficiently parameterized in the existing model components. Deficits have been identified in the dynamics of water masses that determine the oxygen supply to the shelf and export of detritus across the shelf edge; in the mechanisms that determine the cycling of N and P in suboxic/anoxic environments; in processes that regenerate the nutrient ratios in aged upwelling water and govern the role of these waters in open-ocean carbon sequestration; in the quantitative analysis of present-day ecosystem structures and energy flows through the food chain/web. Results of experimental work on expeditions and in the laboratories will be used to improve the model performance for specific time periods for which observations exist in the region, and for the periods of expeditions.