How coastal seas help the ocean absorb carbon dioxide from the atmosphere

The biologically productive North Sea impacts the global climate through exchange of carbon and nutrients with the Atlantic Ocean. A Dutch consortium of scientists will investigate how big this role of the North Sea really is. Under the leadership of the Royal Netherlands Institute for Sea Research (NIOZ), conduct a combination of field studies and computer model simulations will be conducted over the next four years to address this question. NWO has awarded approximately 3 million euros for this project.
 
Innovative studies will quantify the current role of the North Sea, while  the seafloor sediment archive will be unveiled to provide a unique perspective on past changes. Models will be used to determine future effects of environmental and climate change on the North Sea, Atlantic Ocean and ultimately Earth’s climate.

TU Delft's Peter Herman, Professor of Ecological Hydraulic Engineering, and Bram van Prooijen, Associate Professor of Estuarine Dynamics, are involved in the research and part of the consortium.

The North Sea lies between continental Europe and the Atlantic Ocean. Photo: NASA

Coastal seas make up only a small part of the ocean's surface (less than 10%). But because they connect land to the open ocean, they are disproportionately important in global carbon and nutrient cycles. The North Sea is a very productive coastal sea and a lot of carbon dioxide (CO₂) could be sequestered there through physical, biological and sedimentological processes. But much is still unknown about the exact fate of the carbon - especially the balance between outflow to the Atlantic Ocean and storage in seafloor sediments.

The North Sea-Atlantic Exchange (NoSE) project

In the NoSE project, a multidisciplinary consortium (NIOZ, TUD, RUG, UU) will determine the past, present and future role of the North Sea and link it to the larger biogeochemical system of the Atlantic Ocean. This will be done by determining the exchange of carbon and other essential nutrients between the North Sea and the Atlantic Ocean. This exchange will be studied in the Norwegian Trench, the main outflow route to the Atlantic Ocean and the main place where sediments accumulate in the North Sea.  
 
In the Norwegian trench, the scientists will measure the transport and conversion processes that regulate carbon and nutrient exchange between the land, coastal sea and open ocean. They will do this through a combination of research at sea and computer models. Field studies will be used to determine the current processes in the North Sea. By linking these to the sediment data, the researchers hope to gain unique insights into how carbon and nutrient exchange has varied over the past thousands of years and how it may change further into the future.

Schematic figure of the research activities in this project. Figuur: NoSE-project

Human influences change the North Sea

The North Sea is under pressure from overfishing, ocean acidification, eutrophication and in parts a shortage of oxygen. It is crucial to better understand how these human influences affect carbon and nutrient cycling. Such insight will help to understand and project the effects of ongoing environmental change on the North Sea. It may also help to better understand and predict changing biogeochemical interactions between other coastal seas and the global ocean in the future.  
 
The consortium expects that the NoSE project will strengthen existing collaborations in the marine research community in the Netherlands and internationally and will stimulate new collaborations and inspire future work on the large-scale impact of anthropogenic influences on the ocean.

The consortium

The NoSE project is supported by the NWO via the Open Competition ENW-XL programme. It is one of 21 funded projects.

The consortium consists of researchers from NIOZ, Utrecht University, the Technical University of Delft and the University of Groningen.
Other partners: Deltares (NL); National Oceanography Centre, Plymouth Marine Laboratory en University of East Anglia (UK); Helmholtz Centrum Hereon (DE); University of Bergen (NO).

Text/copyright: NIOZ