QS_II | Coast GEm: Greenhouse gas emissions from German coastal waters
The Coast-GEm project focuses on the quantification of greenhouse gas sources and sinks in the coastal area of the German North Sea by using existing monitoring infrastructure in combination with cruises in the coastal zone. A second focus is the Elbe estuary, which is the largest source of nutrients for the German Bight and is likely to have a major impact on coastal greenhouse gas emissions. Coast-GEm is accompanied by the Helmholtz-funded AGRIO project (2025 - 2027, which will create the first continuous coupled hydrodynamic and biogeochemical model system for the river-sea continuum of the Elbe describing all three greenhouse gas pathways.
In Coast GEm, the focus lies on the quantification of greenhouse gas sources and sinks in the coastal area of the German North Sea. We will use existing monitoring infrastructures in a combination with cruises in the North Sea coastal zone to assess coastal emissions of greenhouse gasses. An important focus in the German North Sea coastal zone is the Elbe mouth, which is the largest source of nutrients to the German Bight and will likely exert major control on coastal greenhouse gas emissions. In addition, information from databases and own work on the distribution of greenhouse gasses in the German Bight and the Elbe estuary will be compiled. Whenever possible, data on greenhouse gas concentrations will be converted to emission data and finally made available to the ITMS-community. With our data on coastal greenhouse gas emission, we will contribute to the national data set of observation-based, spatially, temporally and sectorally resolved emission fields.
In the course of other projects (ElbeXtreme, Carmaflux) we have conducted three cruises in 2024. In August the tidal Elbe was investigated with continuous monitoring of all three GHGs. In September we performed a systematic zigzag course with continuous monitoring of CH4 in the Elbe Estuary and southern North Sea. For the first time we were able to assess the northern area of the German Economic zone and East Frisian Wadden sea with the RV Heincke. As we are using different instrumental set-ups, we plan to conduct an intercalibration of these set-ups.
The continuous monitoring in the River Elbe was started in spring 2024, however there are some technical issues to be solved. The established ICOS monitoring station at the estuary, is continuously monitoring dissolved CO2 and we plan to extend the measurements to CH4 in 2025. This site is the most challenging as strong currents, turbid water and biofouling require a lot of maintenance efforts. The marine station Helgoland is using established infrastructure. Our methane sensor is on site and colleagues are also measuring CO2 recently.
Our next steps are to apply a common estimation to convert concentrations of dissolved gases into fluxes, and subsequently how to best include these data into the ITMS community.
CoastGEm is accompanied by the AGRIO project (2025 - 2027) funded by the Helmholtz community establishing the first continuous coupled hydrodynamic and biogeochemical model system by laterally and procedurally connecting existing models for the Elbe river-sea continuum describing all three GHG pathways.
Participating institutions:
- Alfred Wegener Institute Helgoland, Shelf Sea System Ecology
- HEREON, Aquatic Nutrient Cycles
Beteiligte Personen:
