Overarching themes
Fluxes
We investigate fluxes of dissolved components (nutrients, trace elements etc.), gases or particles through the water column and along the land-ocean, sediment-water and sea-ice-water interface. A variety of geochemical tracers are applied to determine diffusive and advective fluxes. Through this approach we
determine budgets and identify sources and sinks in geochemical cycles.
Process understanding
We seek to gain an in-depth process understanding of particle aggregation/disaggregation and particle-water interactions in the water column, formation and transformation/consumption of climate-relevant gases (CH4, DMS, etc.) in sea-ice, water column and sediments, diagenetic alteration of primary
signals and (bio)geochemical pathways in the sediment. Based on such process-oriented investigations, numerical modeling of fluxes and turn-over processes as well as spatial analysis are supported.
Proxies
Elemental, isotopic, mineralogical, and molecular sedimentary signals are used as proxies for (palaeo)environmental reconstructions. We study the formation (biotic / abiotic) of proxies in sea-ice and the water-column, their alteration (biotic / abiotic) during transportation (water-column), at physical (water – sediment; sea-ice - water) and geochemical interfaces and reaction fronts, and validate them by
comparison of predicted and observed data.