Marine Biogeochemistry

WG Transient Tracers

Projects

SFB754 TPA3: Climate-Biogeochemistry interactions in the Tropical Ocean, Vertical and lateral oxygen supply to Oxygen Minimum Zones: A Tracer Release Experiment (OSTRE)

Carbon and transient tracers dynamics: A bi-polar view on Southern Ocean eddies and the changing Arctic Ocean download PDF

Chemistry and Circulation of the Mediterranean Sea download PDF

AtlantOS – a large European project with the vision to improve and innovate Atlantic observing by using the Framework of Ocean Observing to obtain an international, more sustainable, more efficient, more integrated, and fit-for-purpose system. In cooperation with the sensor company KM Contros we contribute to four work packages by development and field testing of new technology (oxygen optode, pCO2 optode, autonomous underway alkalinity titration system).

Lab infrastructure 

Our tools are purge-and-trap systems (PT) that are coupled to gas chromatographs (GCs) equipped with electron capture detectors (ECDs). We are constantly making improvements to our instruments to increase the precision of our measurements, and to increase the range of compounds that we can measure. We do currently have three of these systems in our lab, although most of the time at least one system is away for field work, and another one is being serviced, or in use in the lab for measuring off-line samples.

Most of the samples are measured at sea, using sampling either by ground-glass syringes or ampoules. We do also have the capacity to flame seal ampoules for later onshore measurements in the lab, which is useful if we are not able to supply an instrument and personnel to the cruise in question.

The Medusa system is a sample pre-concentration unit that is connected to a gas-chromatograph mass –spectrometer. The Medusa is designed to accurately measure a wide range of halogenated tracer compounds, such as chlorofluorocarbons (CFCs), perfluorocarbons (PFCs) and HCFCs together with biologically produced halogenated compounds like methyliodide and dibromomethane. The Medusa was originally constructed to measure atmospheric samples but we are intending to measure seaweater samples in addition.